Carrier | 59MN7A | Instruction manual | Carrier 59MN7A Instruction manual

59MN7A
Modulating 4---Way Multipoise Gas Furnace
Series 200
Installation, Start---up, Operating and
Service and Maintenance Instructions
NOTE: Read the entire instruction manual before starting the
installation.
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . 3
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
CODES AND STANDARDS . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS . . . 4
ACCESSORIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
AIR FOR COMBUSTION AND VENTILATION . . . . . . . . . . 9
CONDENSATE TRAP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Upflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Downflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Horizontal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
SERVICE AND MAINTENANCE PROCEDURES . . . . . . . . 73
Cleaning Heat Exchangers . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
SEQUENCE OF OPERATION . . . . . . . . . . . . . . . . . . . . . . . . 85
PARTS REPLACEMENT GUIDE . . . . . . . . . . . . . . . . . . . . . . 90
TABLES
Loose Parts Bag Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Minimum Clearances to Combustible Materials . . . . . . . . . . . . . 6
Minimum Free Area Required . . . . . . . . . . . . . . . . . . . . . . . . . 10
Minimum Space Volumes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Filter Size Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
CONDENSATE DRAIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Upflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Opening Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Downflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Horizontal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Filter Arrangement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
AIR DUCTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Combustion--Air Vent Pipe, Fitting & Cement Material.. . . . . . 45
Ductwork Acoustical Treatment . . . . . . . . . . . . . . . . . . . . . 27
GAS PIPING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
ELECTRICAL CONNECTIONS . . . . . . . . . . . . . . . . . . . . . . . 32
Maximum Equivalent Vent Length . . . . . . . . . . . . . . . . . . . . . . 47
115--V Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
J--Box Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
24--V Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Alternate Power Supplies . . . . . . . . . . . . . . . . . . . . . . . . . . 34
VENTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Special Venting Requirements for Installations in Canada .
Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Venting Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Locating Vent Termination . . . . . . . . . . . . . . . . . . . . . . . . .
Size the Vent and Combustion Air Pipes . . . . . . . . . . . . . . .
Combustion Air and Vent Piping Insulation Guidelines . . .
Configure the Furnace . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installing the Vent Termination . . . . . . . . . . . . . . . . . . . . . .
Venting System Length Calculations . . . . . . . . . . . . . . . . .
START--UP, ADJUSTMENT, AND SAFETY CHECK . . . . . .
Select Setup Switch Positions . . . . . . . . . . . . . . . . . . . . . . . .
40
40
41
41
41
42
42
42
44
47
60
60
Prime Condensate Trap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Purge Gas Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Adjustments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Check Safety Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Air Delivery CFM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Maximum Capacity of Pipe . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Vent Termination Kit for Direct Vent (2--Pipe) Systems . . . . . . 41
Maximum Allowable Exposed Vent Lengths Insulation . . . . . . 46
Deductions from Maximum Equivalent Vent Length . . . . . . . . 47
Altitude Derate Multiplier for U.S.A. . . . . . . . . . . . . . . . . . . . . 68
Blower Off Delay Setup Switch . . . . . . . . . . . . . . . . . . . . . . . . 68
Gas Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Orifice Size and Manifold Pressure . . . . . . . . . . . . . . . . . . . . . 69
Always Ask For
CERTIFIED
Use of the AHRI Certified TM Mark indicates a
manufacturer’s participation in the program. For
verification of certification for individual products,
go to www.ahridirectory.org.
Portions of the text and tables are reprinted from NFPA 54/ANSI
Z223.1--2009E, with permission of National Fire Protection
Association, Quincy, MA 02269 and American Gas Association,
Washington DC 20001. This reprinted material is not the complete
and official position of the NFPA or ANSI on the referenced subject,
which is represented only by the standard in its entirety.
1
Required Notice for Massachusetts Installations
59MN7A
IMPORTANT
The Commonwealth of Massachusetts requires compliance with regulation 248 CMR as follows:
5.08: Modifications to NFPA--54, Chapter 10
2) Revise 10.8.3 by adding the following additional requirements:
a. For all side wall horizontally vented gas fueled equipment installed in every dwelling, building or structure used in
whole or in part for residential purposes, including those owned or operated by the Commonwealth and where the
side wall exhaust vent termination is less than seven (7) feet above finished grade in the area of the venting,
including but not limited to decks and porches, the following requirements shall be satisfied:
1. INSTALLATION OF CARBON MONOXIDE DETECTORS. At the time of installation of the side wall horizontal vented
gas fueled equipment, the installing plumber or gasfitter shall observe that a hard wired carbon monoxide detector with an
alarm and battery back--up is installed on the floor level where the gas equipment is to be installed. In addition, the installing
plumber or gasfitter shall observe that a battery operated or hard wired carbon monoxide detector with an alarm is installed on
each additional level of the dwelling, building or structure served by the side wall horizontal vented gas fueled equipment. It
shall be the responsibility of the property owner to secure the services of qualified licensed professionals for the installation of
hard wired carbon monoxide detectors
a. In the event that the side wall horizontally vented gas fueled equipment is installed in a crawl space or an attic, the hard wired
carbon monoxide detector with alarm and battery back--up may be installed on the next adjacent floor level.
b. In the event that the requirements of this subdivision can not be met at the time of completion of installation, the owner shall
have a period of thirty (30) days to comply with the above requirements; provided, however, that during said thirty (30) day
period, a battery operated carbon monoxide detector with an alarm shall be installed.
2. APPROVED CARBON MONOXIDE DETECTORS. Each carbon monoxide detector as required in accordance with the
above provisions shall comply with NFPA 720 and be ANSI/UL 2034 listed and IAS certified.
3. SIGNAGE. A metal or plastic identification plate shall be permanently mounted to the exterior of the building at a minimum
height of eight (8) feet above grade directly in line with the exhaust vent terminal for the horizontally vented gas fueled
heating appliance or equipment. The sign shall read, in print size no less than one--half (1/2) inch in size, ”GAS VENT
DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS”.
4. INSPECTION. The state or local gas inspector of the side wall horizontally vented gas fueled equipment shall not approve the
installation unless, upon inspection, the inspector observes carbon monoxide detectors and signage installed in accordance
with the provisions of 248 CMR 5.08(2)(a)1 through 4.
5. EXEMPTIONS: The following equipment is exempt from 248 CMR 5.08(2)(a)1 through 4:
(1.) The equipment listed in Chapter 10 entitled ”Equipment Not Required To Be Vented” in the most current edition of
NFPA 54 as adopted by the Board; and
(2.) Product Approved side wall horizontally vented gas fueled equipment installed in a room or structure separate from
the dwelling, building or structure used in whole or in part for residential purposes.
c. MANUFACTURER REQUIREMENTS -- GAS EQUIPMENT VENTING SYSTEM PROVIDED. When the
manufacturer of Product Approved side wall horizontally vented gas equipment provides a venting system design
or venting system components with the equipment, the instructions provided by the manufacturer for installation of
the equipment and the venting system shall include:
1. Detailed instructions for the installation of the venting system design or the venting system components; and
2. A complete parts list for the venting system design or venting system.
d. MANUFACTURER REQUIREMENTS -- GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED. When
the manufacturer of a Product Approved side wall horizontally vented gas fueled equipment does not provide the
parts for venting the flue gases, but identifies “special venting systems”, the following requirements shall be
satisfied by the manufacturer:
1. The referenced “special venting system” instructions shall be included with the appliance or equipment installation
instructions; and
2. The “special venting systems” shall be Product Approved by the Board, and the instructions for that system shall include a
parts list and detailed installation instructions.
e. A copy of all installation instructions for all Product Approved side wall horizontally vented gas fueled equipment,
all venting instructions, all parts lists for venting instructions, and/or all venting design instructions shall remain
with the appliance or equipment at the completion of the installation.
For questions regarding these requirements, please contact the Commonwealth of Massachusetts Board of State Examiners of Plumbers and
Gas Fitters, 239 Causeway Street, Boston, MA 02114. 617--727--9952.
2
!
WARNING
FIRE, EXPLOSION, ELECTRICAL SHOCK, AND
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in dangerous
operation, personal injury, death, or property damage.
Improper installation, adjustment, alteration, service,
maintenance, or use can cause carbon monoxide poisoning,
explosion, fire, electrical shock, or other conditions which
may cause personal injury or property damage. Consult a
qualified service agency, local gas supplier, or your
distributor or branch for information or assistance. The
qualified service agency must use only factory--authorized
and listed kits or accessories when modifying this product.
!
CAUTION
FURNACE RELIABILITY HAZARD
Failure to follow this caution may result in unit component
damage.
Application of this furnace should be indoors with special
attention given to vent sizing and material, gas input rate,
air temperature rise, unit leveling, and unit sizing.
Improper installation, adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause death, personal injury, or property
damage. Consult a qualified installer, service agency, or your
distributor or branch for information or assistance. The qualified
installer or agency must use factory-authorized kits or accessories
when modifying this product. Refer to the individual instructions
packaged with the kits or accessories when installing.
Installing and servicing heating equipment can be hazardous due to
gas and electrical components. Only trained and qualified
personnel should install, repair, or service heating equipment.
Untrained personnel can perform basic maintenance functions such
as cleaning and replacing air filters. All other operations must be
performed by trained service personnel. When working on heating
equipment, observe precautions in literature, on tags, and on labels
attached to or shipped with furnace and other safety precautions
that may apply.
These instructions cover minimum requirements and conform to
existing national standards and safety codes. In some instances,
these instructions exceed certain local codes and ordinances,
especially those that may not have kept up with changing
residential construction practices. We require these instructions as a
minimum for a safe installation.
Follow all safety codes. Wear safety glasses, protective clothing,
and work gloves. Have a fire extinguisher available. Read these
instructions thoroughly and follow all warnings or cautions
included in literature and attached to the unit.
!
CAUTION
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care
and wear appropriate protective clothing, safety glasses and
gloves when handling parts, and servicing furnaces.
This is the safety--alert symbol
. When you see this symbol on
the furnace and in instructions or manuals, be alert to the potential
for personal injury.
Understand the signal words DANGER, WARNING, and
CAUTION. These words are used with the safety--alert symbol.
DANGER identifies the most serious hazards which will result in
severe personal injury or death. WARNING signifies a hazard
which could result in personal injury or death. CAUTION is used
to identify hazards which may result in minor personal injury or
product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability, or
operation.
1. Use only with type of gas approved for this furnace. Refer
to the furnace rating plate.
2. Install this furnace only in a location and position as specified in the “Location” section of these instructions.
3. Provide adequate combustion and ventilation air to the furnace space as specified in “Air for Combustion and Ventilation” section.
4. Combustion products must be discharged outdoors. Connect this furnace to an approved vent system only, as specified in the “Venting” section of these instructions.
5. Never test for gas leaks with an open flame. Use a commercially available soap solution made specifically for the detection of leaks to check all connections, as specified in the
“Gas Piping” section.
6. Always install furnace to operate within the furnace’s intended temperature--rise range with a duct system which has an
external static pressure within the allowable range, as specified in the “Start--Up, Adjustments, and Safety Check”
section. See furnace rating plate.
7. When a furnace is installed so that supply ducts carry air
circulated by the furnace to areas outside the space containing the furnace, the return air shall also be handled by
duct(s) sealed to the furnace casing and terminating outside
the space containing the furnace. See “Air Ducts” section.
8. A gas--fired furnace for installation in a residential garage
must be installed as specified in the warning box in the
“Location” section.
9. The furnace may be used for construction heat provided that
the furnace installation and operation complies with the first
CAUTION in the LOCATION section of these instructions.
10. These Multipoise Gas--Fired Furnaces are CSA design--certified for use with natural and propane gases (see furnace
rating plate) and for installation in alcoves, attics, basements, closets, utility rooms, crawlspaces, and garages. The
furnace is factory--shipped for use with natural gas. A CSA
(A.G.A. and C.G.A.) listed accessory gas conversion kit is
required to convert furnace for use with propane gas.
11. See Table 2 for required clearances to combustible construction.
12. Maintain a 1--in. (25 mm) clearance from combustible materials to supply air ductwork for a distance of 36 in. (914
mm) horizontally from the furnace. See NFPA 90B or local
code for further requirements.
13. These furnaces SHALL NOT be installed directly on carpeting, tile, or any other combustible material other than wood
flooring. In downflow installations, factory accessory floor
base MUST be used when installed on combustible materials and wood flooring. Special base is not required when
this furnace is installed on manufacturer’s Coil Assembly
Part No. CNRV, CNPV, CAP, or CAR or when Coil Box
Part No. KCAKC is used. See Table 2 for clearance to combustible construction information.
3
59MN7A
SAFETY CONSIDERATIONS
59MN7A
INTRODUCTION
The 4--way multipoise Category IV condensing furnace is CSA
design--certified for both direct--vent (2-pipe) and ventilated
combustion air venting installations. (See Fig. 2.) The furnace is
factory--shipped for use with natural gas. The furnace can be
converted in the field for use with propane gas when a
factory-supplied conversion kit is used. Refer to the furnace rating
plate for conversion kit information.
This furnace is not approved for installation in mobile homes,
recreational vehicles, or outdoors.
This furnace is designed for minimum continuous return--air
temperature of 60_F (15_C) db or intermittent operation down to
55_F (13_C) db such as when used with a night setback
thermostat. Return-air temperature must not exceed 80_F (27_C)
db. Failure to follow these return-air temperature limits may affect
reliability of heat exchangers, motors, and controls. (See Fig. 3).
The furnace should be sized to provide 100 percent of the design
heating load requirement plus any margin that occurs because of
furnace model size capacity increments. Heating load estimates can
be made using approved methods available from Air Conditioning
Contractors of America (Manual J); American Society of Heating,
Refrigerating, and Air--Conditioning Engineers; or other approved
engineering methods. Excessive oversizing of the furnace could
cause the furnace and/or vent to fail prematurely.
For accessory installation details, refer to the applicable instruction
literature.
NOTE: Remove all shipping materials, loose parts bag, and
literature before operating the furnace. (See Table 1).
Fundamentals Handbook Chapter 35
Acoustical Lining and Fibrous Glass Duct
S US and CANADA: current edition of SMACNA, NFPA 90B as
tested by UL Standard 181 for Class I Rigid Air Ducts
Gas Piping and Gas Pipe Pressure Testing
S US: NFPA 54/ANSI Z223.1--2009 NFGC; Chapters 5, 6, 7, and 8
and national plumbing codes.
CANADA: CAN/CSA--B149.1--2010, Parts 4, 5, 6, and 9.
In the state of Massachusetts:
S This product must be installed by a licensed plumber or gas fitter.
S When flexible connectors are used, the maximum length shall
not exceed 36 in. (914 mm).
S When lever type gas shutoffs are used they shall be T--handle type.
S The use of copper tubing for gas piping is not approved by the
state of Massachusetts.
Electrical Connections
S US: National Electrical Code (NEC) ANSI/NFPA 70--2011
S CANADA: Canadian Electrical Code CSA C22.1
ELECTROSTATIC DISCHARGE (ESD)
PRECAUTIONS PROCEDURE
!
CAUTION
FURNACE RELIABILITY HAZARD
CODES AND STANDARDS
Failure to follow this caution may result in unit component
damage.
Follow all national and local codes and standards in addition
to these instructions. The installation must comply with
regulations of the serving gas supplier, local building, heating,
plumbing, and other codes. In absence of local codes, the
installation must comply with the national codes listed below and
all authorities having jurisdiction.
In the United States and Canada, follow all codes and standards for
the following:
Electrostatic discharge can affect electronic components.
Take precautions during furnace installation and servicing
to protect the furnace electronic control. Precautions will
prevent electrostatic discharges from personnel and hand
tools which are held during the procedure. These
precautions will help to avoid exposing the control to
electrostatic discharge by putting the furnace, the control,
and the person at the same electrostatic potential.
Safety
1. Disconnect all power to the furnace. Multiple disconnects
may be required. DO NOT TOUCH THE CONTROL
OR ANY WIRE CONNECTED TO THE CONTROL
PRIOR TO DISCHARGING YOUR BODY’S
ELECTROSTATIC CHARGE TO GROUND.
2. Firmly touch the clean, unpainted, metal surface of the furnace chassis which is close to the control. Tools held in a
person’s hand during grounding will be satisfactorily discharged.
3. After touching the chassis, you may proceed to service the
control or connecting wires as long as you do nothing to
recharge your body with static electricity (for example; DO
NOT move or shuffle your feet, do not touch ungrounded
objects, etc.).
4. If you touch ungrounded objects (and recharge your body
with static electricity), firmly touch a clean, unpainted metal
surface of the furnace again before touching control or
wires.
5. Use this procedure for installed and uninstalled (ungrounded) furnaces.
6. Before removing a new control from its container, discharge
your body’s electrostatic charge to ground to protect the
control from damage. If the control is to be installed in a
furnace, follow items 1 through 4 before bringing the control or yourself in contact with the furnace. Put all used and
new controls into containers before touching ungrounded
objects.
S US: National Fuel Gas Code (NFGC) NFPA 54--2009/ANSI
Z223.1--2009 and the Installation Standards, Warm Air Heating
and Air Conditioning Systems ANSI/NFPA 90B
S CANADA: National Standard of Canada, Natural Gas and
Propane Installation Code (NSCNGPIC) CAN/CSA
B149.1--2010
General Installation
S US: NFGC and the NFPA 90B. For copies, contact the National
Fire Protection Association Inc., Batterymarch Park, Quincy,
MA 02269; or for only the NFGC contact the American Gas
Association, 400 N. Capitol, N.W., Washington DC 20001
S CANADA: NSCNGPIC. For a copy, contact Standard Sales,
CSA International, 178 Rexdale Boulevard, Etobicoke
(Toronto), Ontario, M9W 1R3, Canada
Combustion and Ventilation Air
S US: Section 9.3 of the NFPA54/ANSI Z223.1--2009 Air for
Combustion and Ventilation
S CANADA: Part 8 of the CAN/CSA B149.1--2010, Venting
Systems and Air Supply for Appliances
Duct Systems
S US and CANADA: Air Conditioning Contractors Association
(ACCA) Manual D, Sheet Metal and Air Conditioning Contractors
National Association (SMACNA), or American Society of Heating,
Refrigeration, and Air Conditioning Engineers (ASHRAE) 2005
4
ACCESSORIES
See Product Data Sheet for a list of accessories for this product
LOCATION
!
CAUTION
wood flooring (refer to SAFETY CONSIDERATIONS).
S be located close to the chimney or vent and attached to an air
distribution system. Refer to Air Ducts section.
S be provided ample space for servicing and cleaning. Always
comply with minimum fire protection clearances shown in
Table 2 or on the furnace clearance to combustible construction
label.
PERSONAL INJURY AND/OR PROPERTY
DAMAGE HAZARD
!
Improper use or installation of this furnace may result in
premature furnace component failure. This gas furnace may
be used for heating buildings under construction provided
that:
Failure to follow this warning could result in personal injury
or death and unit component damage.
--The furnace is permanently installed with all electrical
wiring, piping, venting and ducting installed according to
these installation instructions. A return air duct is provided,
sealed to the furnace casing, and terminated outside the
space containing the furnace. This prevents a negative
pressure condition as created by the circulating air blower,
causing a flame rollout and/or drawing combustion
products into the structure.
Corrosive or contaminated air may cause failure of parts
containing flue gas, which could leak into the living space.
Air for combustion must not be contaminated by halogen
compounds, which include fluoride, chloride, bromide, and
iodide. These elements can corrode heat exchangers and
shorten furnace life. Air contaminants are found in aerosol
sprays, detergents, bleaches, cleaning solvents, salts, air
fresheners, and other household products. Do not install
furnace in a corrosive or contaminated atmosphere. Make
sure all combustion and circulating air requirements are met,
in addition to all local codes and ordinances.
--The furnace is controlled by a thermostat. It may not be
“hot wired” to provide heat continuously to the structure
without thermostatic control.
--Clean outside air is provided for combustion. This is to
minimize the corrosive effects of adhesives, sealers and
other construction materials. It also prevents the
entrainment of drywall dust into combustion air, which can
cause fouling and plugging of furnace components.
--The temperature of the return air to the furnace is
maintained between 55_F (13_C) and 80_F (27_C), with
no evening setback or shutdown. The use of the furnace
while the structure is under construction is deemed to be
intermittent operation per our installation instructions.
--The air temperature rise is within the rated rise range on
the furnace rating plate, and the gas input rate has been set
to the nameplate value.
--The filters used to clean the circulating air during the
construction process must be either changed or thoroughly
cleaned prior to occupancy.
--The furnace, ductwork and filters are cleaned as necessary
to remove drywall dust and construction debris from all
HVAC system components after construction is completed.
--Verify proper furnace operating conditions including
ignition, gas input rate, air temperature rise, and venting
according to these installation instructions.
General
These furnaces are shipped with materials to assist in proper
furnace installation. These materials are shipped in the main
blower compartment. See Table 1 for loose parts bag contents.
This furnace must:
S be installed so the electrical components are protected from
water.
S not be installed directly on any combustible material other than
WARNING
CARBON MONOXIDE POISONING / COMPONENT
DAMAGE HAZARD
The following types of furnace installations may require
OUTDOOR AIR for combustion due to chemical exposures:
S Commercial buildings
S Buildings with indoor pools
S Laundry rooms
S Hobby or craft rooms
S Chemical storage areas
If air is exposed to the following substances, it should not be used
for combustion air, and outdoor air may be required for
combustion:
S Permanent wave solutions
S Chlorinated waxes and cleaners
S Chlorine based swimming pool chemicals
S Water softening chemicals
S De--icing salts or chemicals
S Carbon tetrachloride
S Halogen type refrigerants
S Cleaning solvents (such as perchloroethylene)
S Printing inks, paint removers, varnishes, etc.
S Hydrochloric acid
S Cements and glues
S Antistatic fabric softeners for clothes dryers
S Masonry acid washing materials
All fuel--burning equipment must be supplied with air for fuel
combustion. Sufficient air must be provided to avoid negative
pressure in the equipment room or space. A positive seal must be
made between the furnace cabinet and the return--air duct to
prevent pulling air from the burner area.
5
59MN7A
7. An ESD service kit (available from commercial sources)
may also be used to prevent ESD damage.
!
WARNING
!
WARNING
FIRE, INJURY OR DEATH HAZARD
FIRE HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
Failure to follow this warning could result in personal
injury, death and/or property damage.
When the furnace is installed in a residential garage, the
burners and ignition sources must be located at least 18 in.
(457 mm) above the floor. The furnace must be located or
protected to avoid damage by vehicles. When the furnace is
installed in a public garage, airplane hangar, or other
building having a hazardous atmosphere, the furnace must
be installed in accordance with the NFPA 54/ANSI
Z223.1--2009 or CAN/CSA B149.2--2010. (See Fig. 5.)
Do not install the furnace on its back or hang furnace with
control compartment facing downward. Safety control
operation will be adversely affected. Never connect
return--air ducts to the back of the furnace. (See Fig. 4.)
Location Relative to Cooling Equipment
59MN7A
The cooling coil must be installed parallel with, or on the
downstream side of the unit to avoid condensation in the heat
exchangers. When installed parallel with the furnace, dampers or
other flow control must prevent chilled air from entering the
furnace. If the dampers are manually operated, they must be
equipped with means to prevent operation of either unit unless the
damper is in the full--heat or full--cool position.
Table 1 – Factory--Supplied Installation Parts
DESCRIPTION
Air Intake Pipe Flange
Vent Pipe Flange
Coupling Flange Gaskets
Sharp Tip Screws (Vent and Inlet Flanges)
Vent Pipe Coupling
Vent Pipe Coupling Clamps
Rubber Drain Elbow
Drain Tube Clamps
1/2---in. CPVC to 3/4---in. PVC Pipe Adapter
Gas Line Grommet
Junction Box Cover
Junction Box Base
Green Ground Screw
Blunt Tip Screws (Junction Box)
Thermostat Wire Grommet
Drain Extension Tube (Z---pipe) (Provided separately in furnace)
QUANTITY
1
1
2
10
1
2
1
4
1
1
1
1
1
3
1
1
Table 2 – Minimum Clearances to Combustible Materials for All Units
POSITION
Rear
Front (Combustion air openings in furnace and in structure)
Required for service
All Sides of Supply Plenum
Sides
Vent
Top of Furnace
CLEARANCE
0 (0 mm)
1 in. (25 mm)
*24 in. (610 mm)
1 in. (25 mm)
0 (0 mm)
0 (0 mm)
1 in. (25 mm)
* Recommended
6
59MN7A
A11588
Fig. 1 -- Dimensional Drawing
7
THE BLOWER IS
LOCATED BELOW THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED UPWARD.
59MN7A
THE BLOWER IS LOCATED
TO THE RIGHT OF THE
BURNER SECTION, AND
AIR CONDITIONED AIR IS
DISCHARGED TO THE LEFT.
THE BLOWER IS
LOCATED TO THE LEFT
OF THE BURNER SECTION,
AND CONDITIONED AIR IS
DISCHARGED TO THE RIGHT.
THE BLOWER IS
LOCATED ABOVE THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED DOWNWARD
A02097
Fig. 2 -- Multipoise Orientations
80
/ 27˚C
60
/ 16˚C
SUPPLY AIR
A10490
Fig. 3 -- Freeze Protection and Return Air Temperature
18-IN. (457.2 mm)
MINIMUM TO BURNERS
A10494
A93044
Fig. 4 -- Prohibited Installations
Fig. 5 -- Installation in a Garage
8
Introduction
Direct Vent (2-- pipe) Applications
When the furnace is installed as a direct vent (2-pipe) furnace, no
special provisions for air for combustion are required. However,
other gas appliances installed in the space with the furnace may
require outside air for combustion. Follow the guidelines below to
insure that other gas appliances have sufficient air for combustion.
Ventilated Combustion Air Applications
When the furnace is installed using the ventilated combustion air
option, the attic or crawlspace must freely communicate with the
outdoor to provide sufficient air for combustion. The combustion
air pipe cannot be terminated in attics or crawlspaces that use
ventilation fans designed to operate during the heating season. If
ventilation fans are present in these areas, the combustion air pipe
must terminate outdoors as a Direct Vent/ 2-Pipe system.
All air for combustion is piped directly to the furnace from a space
that is well ventilated with outdoor air (such as an attic or crawl
space) and the space is well isolated from the living space or
garage. In addition, other gas appliances installed in the space with
the furnace may require outside air for combustion. Follow the
guidelines below to insure that the roof or crawlspace walls have
sufficient free area to provide sufficient air for combustion and
ventilation for the furnaces. The guidelines below can be used to
insure that other gas appliances have sufficient air for combustion.
Provisions for adequate combustion, ventilation, and dilution air
must be provided in accordance with:
S U.S.A. Installations: Section 9.3 of the NFPA 54/ANSI
Z223.1--2009 , Air for Combustion and Ventilation and
applicable provisions of the local building codes.
S Canada: Part 8 of the CAN/CSA--B149.1--2010, Venting
Systems and Air Supply for Appliances.
!
Outdoor Combustion Air Method
1. Provide the space with sufficient air for proper combustion,
ventilation, and dilution of flue gases using permanent horizontal or vertical duct(s) or opening(s) directly communicating with the outdoors or spaces that freely communicate
with the outdoors.
2. Fig. 6 illustrates how to provide TWO OUTDOOR
OPENINGS, one inlet and one outlet combustion and ventilation air opening, to the outdoors.
a. One opening MUST commence within 12 in. (300 mm)
of the ceiling and the second opening MUST commence
within 12 in. (300 mm) of the floor.
b. Size openings and ducts per Fig. 6 and Table 3.
c. TWO HORIZONTAL DUCTS require 1 sq. in. (645 sq.
mm) of free area per 2,000 Btuh (1,100 mm2/kW) of combined input for all gas appliances in the space per Fig. 6 and
Table 3.
d. TWO OPENINGS OR VERTICAL DUCTS require 1
sq. in. (645 sq. mm) of free area per 4,000 Btuh (550
mm2/kW) for combined input of all gas appliances in the
space per Fig. 6 and Table 3.
3. ONE OUTDOOR OPENING requires:
a. 1 sq. in. (645 sq. mm) of free area per 3,000 Btuh (734
mm2/kW) for combined input of all gas appliances in the
space per Fig. 6 and Table 3.
b. Not less than the sum of the areas of all vent connectors in
the space.
The opening shall commence within 12 in. (300 mm) of the
ceiling. Appliances in the space shall have clearances of at least 1
in. (25 mm) from the sides and back and 6 in. (150 mm) from the
front. The opening shall directly communicate with the outdoors or
shall communicate through a vertical or horizontal duct to the
outdoors or spaces (crawl or attic) that freely communicate with the
outdoors.
CAUTION
FURNACE CORROSION HAZARD
Failure to follow this caution may result in furnace damage.
Air for combustion must not be contaminated by halogen
compounds, which include fluoride, chloride, bromide, and
iodide. These elements can corrode heat exchangers and
shorten furnace life. Air contaminants are found in aerosol
sprays, detergents, bleaches, cleaning solvents, salts, air
fresheners, and other household products.
!
WARNING
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
injury or death.
The operation of exhaust fans, kitchen ventilation fans,
clothes dryers, attic exhaust fans or fireplaces could create a
NEGATIVE PRESSURE CONDITION at the furnace.
Make--up air MUST be provided for the ventilation devices,
in addition to that required by the furnace. Refer to the
Carbon Monoxide Poisoning Hazard warning in the venting
section of these instructions to determine if an adequate
amount of make--up air is available.
9
59MN7A
AIR FOR COMBUSTION AND
VENTILATION
Table 3 – Minimum Free Area Required for Each Combustion Air Opening or Duct to Outdoors
TWO HORIZONTAL DUCTS
(1 SQ. IN./2,000 BTUH)
(1,100 SQ. MM/KW)
FURNACE
INPUT
(BTUH)
SINGLE DUCT OR OPENING
(1 SQ. IN./3,000 BTUH)
(734 SQ. MM/KW)
Free Area of
Opening and Duct
Sq. In (Sq. mm)
Round Duct
In. (mm) Dia
20 (12904)
30 (19355)
TWO OPENINGS OR
VERTICAL DUCTS
(1 SQ. IN./4,000 BTUH)
(550 SQ. MM/KW)
Free Area of OpenRound Duct
ing and Duct
In. (mm) Dia.
Sq. In (mm)
Free Area of
Opening and Duct
Sq. In (Sq. mm)
Round Duct
In. (mm) Dia
5 (127)
14 (8696)
5 (127)
10 (6452)
4 (102)
6 (152)
20 (13043)
5 (127)
15 (9678)
5 (127)
40 (25807)
7 (178)
27 (17391)
6 (152)
20 (12904)
5 (127)
50 (32258)
8 (203)
34 (21739)
7 (178)
25 (16130)
6 (152)
60 (38709)
9 (229)
40 (26087)
7 (178)
30 (19355)
6 (152)
70 (45161)
*Not all families have these models.
10 (254)
47 (30435)
8 (203)
35 (22581)
7 (178)
40,000*
60,000
80,000
100,000
120,000
140,000*
EXAMPLES: Determining Free Area
FURNACE
TOTAL INPUT
100,000
+
30,000
=
(130,000 divided by 4,000)
=
32.5 Sq. In. for each two Vertical Ducts or Openings
60,000
+
40,000
=
(100,000 divided by 3,000)
=
33.3 Sq. In. for each Single Duct or Opening
+
30,000
=
(110,000 divided by 2,000)
=
55.0 Sq. In. for each two Horizontal Ducts
80,000
Table 4 – Minimum Space Volumes for 100% Combustion, Ventilation and Dilution Air from Outdoors
OTHER THAN FAN-ASSISTED TOTAL
(1,000’S BTUH GAS INPUT RATE)
30
ACH
40
FAN-ASSISTED TOTAL
(1,000’S BTUH GAS INPUT RATE)
50
40
60
80
100
120
140
Space Volume Ft3 (M3)
0.60
1,050
(29.7)
1,400
(39.6)
1,750
(49.5)
1,400
(39.6)
1,500
(42.5)
2,000
(56.6)
2,500
(70.8)
3,000
(84.9)
3,500
(99.1)
0.50
1,260
(35.6)
1,680
(47.5)
2,100
(59.4)
1,680
(47.5)
1,800
(51.0)
2,400
(67.9)
3,000
(84.9)
3,600
(101.9)
4,200
(118.9)
0.40
1,575
(44.5)
2,100
(59.4)
2,625
(74.3)
2,100
(59.4)
2,250
(63.7)
3,000
(84.9)
3,750
(106.1)
4,500
(127.3)
5,250
(148.6)
0.30
2,100
(59.4)
2,800
(79.2)
3,500
(99.1)
2,800
(79.2)
3,000
(84.9)
4,000
(113.2)
5,000
(141.5)
6,000
(169.8)
7,000
(198.1)
0.20
3,150
(89.1)
4,200
(118.9)
5,250
(148.6)
4,200
(118.9)
4,500
(127.3)
6,000
(169.8)
7,500
(212.2)
9,000
(254.6)
10,500
(297.1)
0.10
6,300
(178.0)
8,400
(237.8)
10,500
(297.3)
8,400
(237.8)
9,000
(254.6)
12,000
(339.5)
15,000
(424.4)
18,000
(509.2)
21,000
(594.1)
0.00
NP
NP
NP
NP
NP
NP
NP
NP
NP
NP = Not Permitted
1 SQ IN.
PER 4000
BTUH*
B
DUCTS
TO
OUTDOORS
1 SQ IN.
PER 2000
BTUH*
(305mm) 12″ MAX
A
D
VENT
THROUGH
ROOF
12″ (305mm)
MAX
F
1 SQ IN.
PER
4000
BTUH*
OUTDOORS
(305mm) 12″ MAX
1 SQ IN.
PER 2000
BTUH*
CIRCULATING
AIR DUCTS
DUCTS
TO
OUTDOORS
CLEARANCE IN FRONT
OF COMBUSTION AIR
OPENINGS SHALL BE
AT LEAST 3 IN.
(76mm)
59MN7A
WATER HEATER
1 SQ IN.
PER
4000
BTUH*
E
G
12″ (305mm)
MAX
C
12″ MAX
(305mm)
CIRCULATING AIR DUCTS
DUCT
TO
OUTDOORS
1 SQ IN.
PER 4000
BTUH*
*Minimum dimensions of 3--- in. (76 mm).
NOTE: Use any of the following combinations of openings:
A&BC&DD&EF&G
A03174
Fig. 6 -- Air for Combustion, Ventilation, and Dilution for Outdoors
10
!
CAUTION
FROZEN AND BURST WATER PIPE HAZARD
Failure to protect against the risk of freezing may result in
property damage.
Special precautions MUST be made if installing furnace in an
area which may drop below freezing. This can cause improper
operation or damage to equipment. If furnace environment
has the potential of freezing, the drain trap and drain line must
be protected. The use of electric heat tape or RV antifreeze is
recommended for these installations.
!
CAUTION
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in burst water pipes
and/or property damage.
If a condensate pump is installed, a plugged condensate drain
or a failed pump may cause the furnace to shut down. Do not
leave the home unattended during freezing weather without
turning off water supply and draining water pipes or otherwise
protecting against the risk of frozen pipes.
DO NOT trap the drain line in any other location than at the
condensate drain trap supplied with the furnace. If possible, DO
NOT route the drain line where it may freeze. The drain line must
terminate at an inside drain to prevent freezing of the condensate
and possible property damage.
Special precautions MUST be made if installing furnace in an area
which may drop below freezing. This can cause improper
operation or damage to the equipment. If the furnace environment
has the potential of freezing, the drain trap and drain line must be
protected. Use 3 to 6 watt per foot at 115 volt, 40_F (4_C)
self--regulating shielded and water proof heat tape. Wrap the drain
trap and drain line with the heat tape and secure with the ties.
Follow the heat tape manufacturer’s recommendations. Prime the
trap before furnace operation.
Condensate Trap--Upflow Orientation
When the furnace is installed in the upflow position, it is not
necessary to relocate the condensate trap or associated tubing.
Refer to Fig. 7 for upflow condensate trap information. Refer to
Condensate Drain section for information how to install the
condensate drain.
Condensate Trap--Downflow Orientation.
When the furnace is installed in the downflow position, the
factory--installed trap will be located at the upper left corner of the
collector box. When the furnace is installed in the downflow
orientation, the factory--installed trap must be relocated for proper
condensate drainage.
To Relocate the Condensate Trap:
S Orient the furnace in the downflow position.
S Fig. 8 shows the condensate trap and tubing before and after
relocation.
S Refer to the appropriate figure to begin the trap conversion.
S Refer to Condensate Drain section for information how to install
the condensate drain.
Condensate Trap--Horizontal Orientation.
When the furnace is installed in the horizontal right position, the
factory--installed trap will be located at the bottom left corner of the
collector box. When the furnace is installed in the horizontal left
position, the factory--installed trap will be located at the top of the
collector box. The trap must be repositioned on the collector box
for proper condensate drainage.
When the furnace is installed as a direct--vent furnace, a
field--supplied, accessory Horizontal Installation kit (trap grommet)
is required for all direct--vent horizontal installations (only). The
kit contains a rubber casing grommet designed to seal between the
furnace casing and the condensate trap. (See Fig. 17.)
NOTE: The Horizontal Installation Kit (trap grommet) is NOT
required for single--pipe, ventilated combustion air, or other
non--direct--vent applications.
NOTE: The condensate trap extends below the side of the casing
the horizontal position. A minimum of 2 in. (51 mm) of clearance
is required between the casing side and the furnace platform for the
trap to extend out of the casing in the horizontal position. To allow
for servicing the trap, the condensate drain tube in the loose parts
bag can be modified to make a coupler to allow for future service
of the condensate trap and drain line. Allow at least 1/4--in. (6
mm) per foot of slope away from the furnace in horizontal sections
of drain line.
To Relocate the Condensate Trap:
S Remove the knockout in the casing for the Casing Grommet.
S Install the grommet in the casing.
NOTE:
This grommet is only required for Direct--Vent
applications.
S Orient the furnace in the desired position.
S Allow for 2 in. (51 mm) of clearance underneath the furnace for
the condensate trap and drain line.
S Fig. 9 shows the condensate trap and tubing before and after
relocation in the horizontal right position.
S Fig. 10 shows the condensate trap and tubing before and after
relocation in the horizontal left position.
S Refer to the appropriate figure to begin the trap conversion.
S Refer to Condensate Drain section for information how to install
the condensate drain.
11
59MN7A
CONDENSATE TRAP
Vent Pipe Clamp
Condensate Trap
Relief Port
Collector Box
Plugs
Vent Elbow Clamp
Vent Elbow
Collector Box
Plug
59MN7A
Condensate Trap
Relief Port
Pressure Switch
Port
Condensate Trap
Outlet
A11306
Fig. 7 -- Upflow Trap Configuration
(Appearance May Vary)
12
Remove pressure switch tube from
pressure switch port.
Remove relief tube from relief
port on condensate trap.
Loosen clamp on inlet
to vent elbow.
Remove middle and bottom plugs.
DO NOT DISCARD.
7
Install plugs on
open ports on
collector box.
Attach condensate trap
with screw to collector
box.
Connect relief tube to
port on collector box.
9
Trim excess tube.
Connect pressure switch
tube to port on collector box.
Connect relief tube to
relief port on condensate
trap.
Rotate elbow to
desired position and
tighten clamp to
15 lb.-in.
Align condensate trap
over middle and bottom
ports of collector box.
Slide tube in stand-offs
to adjust length.
A11585
Fig. 8 -- Downflow Trap Configuration
(Appearance May Vary)
13
59MN7A
Remove tube from
relief port.
Remove trap from
collector box.
Remove plug from
collector box.
DO NOT DISCARD.
59MN7A
If alternate vent position
is required, loosen clamp
on inlet of vent elbow.
Remove trap from
collector box.
Unconverted Factory Trap Configuration
As Viewed in the Horizontal Right Orientation
Slide relief tube in
stand-offs to adjust length.
Attach condensate trap
to collector box with
screw.
Vent elbow shown in alternate
orientation. Tighten clamp on
inlet to vent elbow 15 lb.-in.
Install plug in open
port on collector box.
Align trap over middle and
right-hand port on collector box.
Horizontal Right Trap Configuration
A11278
Fig. 9 -- Horizontal Right Trap Configuration
(Appearance May Vary)
14
Remove trap from
collector box.
If alternate vent position
is required, loosen clamp
on vent elbow inlet.
Remove relief tube
from relief port on
condensate trap.
59MN7A
Remove pressure switch tube
from port on collector box.
Remove relief tube
from port on collector
box.
Remove middle and right
plug from collector box.
DO NOT DISCARD
Unconverted Factory Trap Configuration
As Viewed in the Horizontal Left Orientation
Install plugs in open
ports on collector box.
Rotate elbow to
desired position and
torque clamp on inlet
15 lb.-in.
Connect relief tube to
port on collector box.
Slide relief tube in
stand-offs to adjust
length.
Trim excess tube.
Route pressure switch tube
underneath relief tube and
connect to port on collector box.
Attach condensate
trap to collector box
with screw.
Align trap over middle
and right-hand port on
collector box.
Connect relief tube to
relief port on condensate
trap.
Horizontal Left Trap Configuration
A11586
Fig. 10 -- Horizontal Left Configuration
(Appearance May Vary)
15
CONDENSATE DRAIN CONNECTION
!
CAUTION
FROZEN AND BURST WATER PIPE HAZARD
Failure to protect against the risk of freezing may result in
property damage.
Special precautions MUST be made if installing furnace in an
area which may drop below freezing. This can cause improper
operation or damage to equipment. If furnace environment
has the potential of freezing, the drain trap and drain line must
be protected. The use of electric heat tape or RV antifreeze is
recommended for these installations.
59MN7A
!
CAUTION
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in burst water pipes
and/or property damage.
If a condensate pump is installed, a plugged condensate drain
or a failed pump may cause the furnace to shut down. Do not
leave the home unattended during freezing weather without
turning off water supply and draining water pipes or otherwise
protecting against the risk of frozen pipes.
DO NOT trap the drain line in any other location than at the
condensate drain trap supplied with the furnace. If possible, DO
NOT route the drain line where it may freeze. The drain line must
terminate at an inside drain to prevent freezing of the condensate
and possible property damage.
Special precautions MUST be made if installing furnace in an area
which may drop below freezing. This can cause improper
operation or damage to the equipment. If the furnace environment
has the potential of freezing, the drain trap and drain line must be
protected. A self--regulating, shielded and waterproof heat tape
rated at 3 to 6 watt per foot at 115 volt, 40_F (4_C) may be used
to help provide freeze protection. Wrap the drain trap and drain
line with the heat tape and secure with the ties. Follow the heat
tape manufacturer’s recommendations. Prime the trap before
furnace operation.
Upflow/Downflow Orientation
In the Upflow or Downflow orientation, the condensate trap is
inside the furnace casing. The condensate drain must be routed
from the trap through the furnace casing. The condensate drain can
be routed through the left or right side of the casing. (The left or
right side is as you are viewing/facing the furnace from the front.)
The furnace condensate drain can be connected to the Air
Conditioning condensate drain as shown in Fig. 12.
NOTE: On narrower casings, it may be easier to remove the
condensate trap, connect the drain line components and re-install
the condensate trap. Read the steps thoroughly to familiarize
yourself with the required steps.
For Right Side Condensate Drain:
1. Remove the 7/8--in. knock--out from the right side of the
casing. (See Fig. 11 .)
2. Remove the pre--formed rubber drain elbow and two spring
clamps from the loose parts bag.
3. Slide a spring clamp 1 inch (25 mm) down the plain end
(the end without the formed grommet) of the drain elbow.
4. From inside the casing, insert the formed grommet end of
the elbow through the 7/8--in. knockout in the casing.
5. Pull the grommet through the casing from the outside until
it is seated in the knockout
6. Attach the plain end of the drain elbow to the outlet stub on
the drain trap. Secure the drain tube to the trap with the
spring clamp.
The remaining drain line can be constructed from field supplied
1/2--in. CPVC or 3/4--in. PVC pipe, in compliance with local
building codes. A factory--supplied 1/2--in. CPVC to 3/4--in. PVC
adapter is supplied in the loose parts bag for use as required.
7. Install the adapter or connect the 1/2--in. CPVC pipe by
sliding a spring clamp over the open end of the grommet on
the outside the furnace casing.
8. Open the spring clamp and insert the long end of the
adapter or the 1/2--in. CPVC pipe into the outlet stub on the
drain tube.
9. Connect additional condensate piping to a code--approved
drain, or to a condensate pump approved for use with acidic
furnace condensate and compatible with mineral and
vegetable oils, such as canola oil.
Allow at least 1/4-in. (6 mm) per foot of slope away from the
furnace in horizontal sections of drain line.
For Left Side Condensate Drain Connection:
1. For left side condensate drainage, the drain line is routed
from the condensate trap, behind the inducer (upflow) or
gas valve (downflow) and out through the left side of the
furnace casing. A pre-formed 1/2--in. CPVC “Z-pipe” is
provided with the furnace. The Z-pipe is long enough to
extend across the casing for drain connections.
2. The Z-pipe is connected to the condensate trap and the
outside of the furnace by modifying the formed rubber
drain elbow as shown in Fig. 16.
3. Locate the Z-pipe. Remove the pre-formed drain elbow and
four spring clamps from the loose parts bag.
4. Remove the formed grommet from the rubber drain elbow
by cutting the elbow along the vertical line located about
1--3/8 in. (35 mm) away from the formed grommet. See Fig.
14. DO NOT DISCARD THE FORMED GROMMET OR
THE RUBBER ELBOW. Both of these pieces will be used.
Assemble and route the drain line to the opposite side of the
furnace as detailed below:
5. Remove the knock-out from the left side of the casing. (See
Fig. 11.)
6. From the outside of the casing, insert the angled end of the
Z-pipe through drain hole in the side left of the casing and
behind the inducer or gas valve. Allow the Z-pipe to
temporarily rest on the blower shelf (upflow) or burner box
(downflow).
7. After inserting the Z pipe through the casing, slide a spring
clamp over each end of the Z pipe.
8. From inside the casing, insert the short end of the formed
grommet cut from the rubber drain elbow through the
7/8-in. drain knockout in the casing.
9. Pull the grommet through the casing from the outside until
it is seated in the knockout.
10. Align the Z-pipe with the long end of the grommet inside
the furnace and insert slightly. The angled end of the tube at
the other side of the casing should be facing the front of the
furnace.
11. Slide a spring clamp over the end of the remaining rubber
drain elbow.
12. Attach the drain elbow to the angled end of Z-pipe and the
drain trap outlet stub. Adjust the length of Z-pipe inserted
into the grommet at the opposite side of the furnace as
necessary for proper fit and positioning. In both upflow and
downflow orientations, the Z-pipe should NOT be resting
on any sheet metal parts.
16
13. Secure the rubber elbow to the drain trap and the Z-pipe
with spring clamps.
14. Secure the grommet to the Z-pipe with the spring clamp.
The remaining drain line can be constructed from field supplied
1/2--in. CPVC or 3/4--in. PVC pipe, in compliance with local
building codes. A factory-supplied 1/2--in. CPVC to 3/4--in. PVC
adapter is supplied in the loose parts bag for use as required.
15. Install the adapter or connect the 1/2--in. CPVC pipe by
sliding a spring clamp over the open end of the grommet on
the outside the furnace casing.
16. Open the spring clamp and insert the long end of the
adapter or the 1/2--in. CPVC pipe into the outlet stub on the
drain tube.
17. Connect additional condensate piping to a code-approved
drain, or to a condensate pump approved for use with acidic
furnace condensate and compatible with mineral and
vegetable oils, such as canola oil.
10. Connect additional condensate piping to a code--approved
drain, or to a condensate pump approved for use with acidic
furnace condensate and compatible with mineral and
vegetable oils, such as canola oil.
Allow at least 1/4-in. (6 mm) per foot of slope away from the furnace in horizontal sections of drain line.
Horizontal Orientation
CAUTION
!
1. In the Horizontal orientation, a field supplied accessory
drain trap grommet is required to seal the gap between the
casing and the condensate trap for direct vent applications,
only. The grommet is NOT required for single--pipe, or other non--direct--vent applications.
2. The condensate trap outlet extends 2 in. (51 mm) below the
furnace casing. To allow for servicing the trap, the
condensate drain tube in the loose parts bag can be modified
to make a coupler to allow for future service of the
condensate trap and drain line.
3. Remove the knock-out for the condensate trap in the side of
the casing.
4. Install the drain trap grommet in the casing if required for
direct vent applications. If necessary, remove the trap, install
the grommet and re-install the trap.
5. Remove the pre-formed rubber drain elbow, and two spring
clamps from the loose parts bag.
6. Remove the formed grommet on the elbow to create an
elbow or straight connector. (See Fig. 14.)
7. Connect the cut elbow or grommet to the outlet of the
condensate trap with 1 spring clamp.
The remaining drain line can be constructed from field--supplied
1/2--in. CPVC or 3/4--in. PVC pipe, in compliance with local building codes. A factory--supplied 1/2--in. CPVC to 3/4--in. PVC adapter
is supplied in the loose parts bag for use as required.
8. Install the adapter or connect the 1/2--in. CPVC pipe by
sliding a spring clamp over the open end of the elbow or
grommet on the outside the furnace casing.
9. Open the spring clamp and insert the long end of the
adapter or the 1/2--in. CPVC pipe into the outlet stub on the
drain tube.
59MN7A
Allow at least 1/4-in. (6 mm) per foot of slope away from the furnace in horizontal sections of drain line.
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care
and wear appropriate protective clothing, safety glasses and
gloves when handling parts, and servicing furnaces.
A11305
Fig. 11 -- Knockout Removal
OPEN STAND
PIPE FOR
A/C OR
HUMIDIFIER
DRAIN
TEE
TO OPEN
DRAIN
A11276
Fig. 12 -- Example of Field Drain Attachment
17
INSTALL CLAMPS ON DRAIN TUBE
ATTACH DRAIN TUBE TO CONDENSATE
DRAIN TRAP
PULL DRAIN STUB
THROUGH CASING
NOTE: Trap grommet is required only for direct-vent
applications.
Remove knockout.
Install grommet before
relocating condensate
trap.
59MN7A
OPEN SPRING CLAMP
INSERT FACTORYïSUPPLIED 1/2ïIN. CPVC
TO 3/4ïIN. PVC ADAPTER OR 1/2ïIN. CPVC PIPE
*CLAMP MAY BE LOCATED ON OUTSIDE OF DRAIN
TUBE
A11342A
A11582
Fig. 13 -- Formed Tube Grommet
Fig. 15 -- Horizontal Drain Trap Grommet
A11581
Fig. 14 -- Modify Drain Tube
A11583A
Fig. 16 -- Drain Trap Connection and Routing
(Appearance May Vary)
18
NOTE: This furnace is certified to leak 2% or less of nominal air
conditioning CFM delivered when pressurized to 1--inch water
column with all present air inlets, air outlets, and plumbing and
electrical ports sealed, including bottom closure in upflow and
horizontal applications.
Upflow Installation
NOTE: The furnace must be pitched as shown in Fig. 22 for
proper condensate drainage.
Supply Air Connections
For a furnace not equipped with a cooling coil, the outlet duct shall
be provided with a removable access panel. This opening shall be
accessible when the furnace is installed and shall be of such a size
that the heat exchanger can be viewed for possible openings using
light assistance or a probe can be inserted for sampling the air
stream. The cover attachment shall prevent leaks.
Connect supply--air duct to flanges on furnace supply--air outlet.
Bend flange upward to 90_ with wide duct pliers. (See Fig. 19.)
The supply--air duct must be connected to ONLY the furnace
supply--outlet--air duct flanges or air conditioning coil casing
(when used). DO NOT cut main furnace casing side to attach
supply air duct, humidifier, or other accessories. All accessories
MUST be connected to duct external to furnace main casing.
Return Air Connections
!
WARNING
FIRE HAZARD
A failure to follow this warning could cause personal injury,
death and/or property damage.
Never connect return--air ducts to the back of the furnace.
Follow instructions below.
The return--air duct must be connected to bottom, sides (left or
right), or a combination of bottom and side(s) of main furnace
casing. Bypass humidifier may be attached into unused return air
side of the furnace casing. (See Fig. 23, 24, 25.)
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return--air opening. Remove this panel when bottom return
air is used. This panel may be used as the bottom closure of an
accessory bottom return air box, or discarded. To remove bottom
closure panel, perform the following:
1. Tilt or raise furnace and remove 4 screws holding bottom
plate. (See Fig. 21.)
2. Remove bottom plate.
3. Remove bottom closure panel.
4. Reinstall bottom plate and screws.
Side Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return--air opening. This panel MUST be in place when
only side return air is used.
NOTE: Side return--air openings can be used in UPFLOW and
some HORIZONTAL configurations. Do not use side return--air
openings in DOWNFLOW configuration. (See Fig. 23, 24, 25.)
Leveling Legs (If Desired)
In upflow position with side return inlet(s), leveling legs may be
used. (See Fig. 20.) Install field--supplied, 5/16 x 1--1/2 in. (8 x 38
mm) (max) corrosion--resistant machine bolts, washers and nuts.
NOTE: Bottom closure must be used when leveling legs are used.
It may be necessary to remove and reinstall bottom closure panel to
install leveling legs. To remove bottom closure panel, see Item 1 in
Bottom Return Air Inlet section in Step 1 above.
To install leveling legs:
1. Position furnace on its back. Locate and drill a hole in each
bottom corner of furnace.
2. For each leg, install nut on bolt and then install bolt with
nut in hole. (Install flat washer if desired.)
3. Install another nut on other side of furnace base. (Install flat
washer if desired.)
4. Adjust outside nut to provide desired height, and tighten inside nut to secure arrangement.
5. Reinstall bottom closure panel if removed.
Downflow Installation
NOTE: The furnace must be pitched as shown in Fig. 22 for
proper condensate drainage.
Supply Air Connections
NOTE: For downflow applications, this furnace is approved for
use on combustible flooring when any one of the following 3
accessories are used:
S Special Base, KGASB
S Cased Coil Assembly Part No. CNPV, CNRV, CAP, or CAR
S Coil Box Part No. KCAKC
1. Determine application being installed from Table 6.
2. Construct hole in floor per Table 6 and Fig. 18.
3. Construct plenum to dimensions specified in Table 6 and
Fig. 18.
4. Install special base coil assembly or coil box as shown in in
Fig. 18.
NOTE: It is recommended that the perforated supply--air duct
flanges be completely removed from furnace when installing the
furnace on a factory--supplied cased coil or coil box. To remove the
supply--air duct flange, use wide duct pliers or hand seamers to
bend flange back and forth until it breaks off. Be careful of sharp
edges. (See Fig. 19.)
!
CAUTION
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care
and wear appropriate protective clothing, safety glasses and
gloves when handling parts, and servicing furnaces.
Connect supply--air duct to supply--air outlet on furnace. Bend
flange inward past 90_ with wide duct pliers (See Fig. 19.) The
supply--air duct must be connected to ONLY the furnace supply
outlet or air conditioning coil casing (when used). When installed
on combustible material, supply--air duct must be connected to
ONLY the factory--approved accessory subbase, or a
factory--approved air conditioning coil casing. DO NOT cut main
furnace casing to attach supply side air duct, humidifier, or other
accessories. All accessories MUST be connected to duct external to
furnace casing.
Return Air Connections
!
WARNING
FIRE HAZARD
A failure to follow this warning could cause personal injury,
death and/or property damage.
Never connect return--air ducts to the back of the furnace.
Follow instructions below.
The return--air duct must be connected to return--air opening
(bottom inlet). DO NOT cut into casing sides (left or right).
19
59MN7A
INSTALLATION
Bypass humidifier connections should be made at ductwork or coil
casing sides exterior to furnace. (See Fig. 24.)
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return--air opening. Remove and discard this panel when
bottom return air is used in downflow applications. To remove
bottom closure panel, perform the following:
1. Tilt or raise furnace and remove 4 screws holding bottom
plate. (See Fig. 21.)
2. Remove bottom plate.
3. Remove bottom closure panel.
4. Reinstall bottom plate and screws.
Horizontal Installation
59MN7A
NOTE: The furnace must be pitched forward as shown in Fig. 22
for proper condensate drainage.
WARNING
!
FIRE, EXPLOSION, AND CARBON MONOXIDE
POISONING HAZARD
Failure to follow this warning could result in personal
injury, death, or property damage.
Do not install the furnace on its back or hang furnace with
control compartment facing downward. Safety control
operation will be adversely affected. Never connect
return--air ducts to the back of the furnace.
!
CAUTION
MINOR PROPERTY HAZARD
Failure to follow this caution may result in minor property
damage.
Local codes may require a drain pan under entire furnace and
condensate trap when a condensing furnace is used in an attic
application or over a finished ceiling.
The furnace can be installed horizontally in an attic or crawlspace
on either the left--hand (LH) or right--hand (RH) side. The furnace
can be hung from floor joists, rafters or trusses or installed on a
non--combustible platform, blocks, bricks or pad.
bottom of furnace is used for return air connection. See Fig. 26 for
proper orientation of roll--out shield.
Supply Air Connections
For a furnace not equipped with a cooling coil, the outlet duct shall
be provided with a removable access panel. This opening shall be
accessible when the furnace is installed and shall be of such a size
that the heat exchanger can be viewed for possible openings using
light assistance or a probe can be inserted for sampling the air
stream. The cover attachment shall prevent leaks.
Connect supply--air duct to flanges on furnace supply--air outlet.
Bend flange upward to 90_ with wide duct pliers. (See Fig. 19.)
The supply--air duct must be connected to ONLY the furnace
supply--outlet--air duct flanges or air conditioning coil casing
(when used). DO NOT cut main furnace casing side to attach
supply air duct, humidifier, or other accessories. All accessories
MUST be connected to duct external to furnace main casing.
Return Air Connections
The return--air duct must be connected to bottom of the furnace.
The side of casing that faces downward may also be used for return
air connection. A combination of the bottom and downward
facing side may also be used. Bypass humidifier may be attached
into unused return air side of the furnace casing. (See Fig. 25.)
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return--air opening. Remove this panel when bottom return
air is used. This panel may be used as a roll--out shield or discard.
To remove bottom closure panel, perform the following:
1. Tilt or raise furnace and remove 4 screws holding bottom
plate. (See Fig. 21.)
2. Remove bottom plate.
3. Remove bottom closure panel.
4. Reinstall bottom plate and screws.
Side Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return--air opening. This panel MUST be in place when
side return air inlet(s) are used without a bottom return air inlet.
Not all horizontal furnaces are approved for side return air
connections (See Fig. 25.)
Filter Arrangement
!
FIRE, CARBON MONOXIDE AND POISONING
HAZARD
Platform Furnace Support
Construct working platform at location where all required furnace
clearances are met. (See Table 2 and Fig. 26.) For furnaces with
1--in. (25 mm) clearance requirement on side, set furnace on
non--combustible blocks, bricks or angle iron. For crawlspace
installations, if the furnace is not suspended from the floor joists,
the ground underneath furnace must be level and the furnace set on
blocks or bricks.
Suspended Furnace Support
The furnace must be supported under the entire length of the
furnace with threaded rod and angle iron. (See Fig. 27.) Secure
angle iron to bottom of furnace as shown.
Roll-- Out Protection
Provide a minimum 12--in. x 22--in. (305 x 559 mm) piece of sheet
metal for flame roll--out protection in front of burner area for
furnaces closer than 12--in. (305 mm) above the combustible deck
or suspended furnaces closer than 12--in. (305 mm) to joists. The
sheet metal MUST extend underneath the furnace casing by 1--in.
(25 mm) with the door removed.
The bottom closure panel on furnaces of widths 17--1/2--in. (445
mm) and larger may be used for flame roll--out protection when
WARNING
Failure to follow this warning could result in fire, personal
injury or death.
Never operate a furnace without a filter or filtration device
installed. Never operate a furnace with filter or filtration
device access doors removed.
There are no provisions for an internal filter rack in these furnaces.
An external filter is required.
The furnace is shipped with a factory-supplied Media Filter
Cabinet. The Media Filter Cabinet uses either a standard 1-inch (25
mm) filter or 4-inch (102 mm) wide Media Filter which can be
purchased separately. A field supplied accessory air cleaner may
also be used in place of the media cabinet.
The Media Cabinet is sized for bottom return applications for use
in upflow, downflow and horizontal applications. A 16--inch (406
mm) Media Cabinet is shipped with the 14--3/16-in. (360 mm)
furnace and includes block-off plates
For upflow side return applications, the Media Cabinet (or field
supplied accessory air cleaner) can be installed on the side of the
furnace or side and bottom when a bottom plenum is used. (See
Fig. 17 and 23.)
20
For downflow applications, the Media Cabinet (or field supplied
accessory air cleaner) must only be connected to the bottom
opening on the furnace. See Fig. 17 and 24.
For horizontal applications, the Media Cabinet (or field supplied
accessory air cleaner) for all models can be connected to the
bottom opening on the furnace. For side return use in the
horizontal position, refer to Fig. 25. If both side and bottom
openings are used in Fig. 25, each opening used will require a
filter.
The media cabinet (or field supplied accessory air cleaner) can also
be installed in the common return duct prior to entering the return
air opening in any orientation.
Refer to the instructions supplied with Media Cabinet or accessory
air filter for assembly and other details. See Table 5 for filter size
details.
Table 5 – Filter Size Information -- In. (mm)
FURNACE CASING WIDTH
17---1/2 (445)
21 (533)
24---1/2 (622)
SIDE RETURN
16 x 25 x 3/4
(406 x 635 x 19)
16 x 25 x 3/4
(406 x 635 x 19)
16 x 25 x 3/4
(406 x 635 x 19)
FILTER SIZE
BOTTOM RETURN
16 x 25 x 3/4
(406 x 635 x 19)
20 x 25 x 3/4
(508 x 635 x 19)
24 x 25 x 3/4
(610 x 635 x 19)
FILTER TYPE
Washable*
Washable*
Washable*
59MN7A
* Recommended to maintain air filter face velocity. See Product Data for part number.
Air Filter Located in Filter Cabinet
FILTER CABINET HEIGHT --- IN (MM)
16 (406)
20 (508)
24 (610)
FILTER SIZE --- IN (MM)
(1) 16 x 25 x 3/4*
(406 x 635 x 19) or
(1) 16 x 25 x 4--- 5/16
(406 x 635 x 110)
(1) 20 x 25 x 3/4*
(508 x 635 x 19) or
(1) 20 x 25 x 4--- 5/16
(508 x 635 x 110)
(1) 24 x 25 x 3/4*or
(610 x 635 x 19) or
(1) 24 x 25 x 4--- 5/16
(610 x 635 x 110)
* Filters with a side return ---air may have a different filter size. Measure the filter to obtain the correct size.
* Recommended to maintain air filter face velocity. See Product Data for part number.
21
FILTER TYPE
Washable or Media*
Washable or Media*
Washable or Media*
21-in. Furnace
14-3/16 and 17-1/2-in.
Furnace
4-in.
Block Off
Plate
4-Ton or less, AC
capacity airflow
1/2-in.
Screws
20-in. Media Cabinet
59MN7A
16-in. Media Cabinet
Media Cabinet Installation
Side Return
Media Cabinet Installation Option for
4-Ton or Less A/C Capacity
21- or 24-1/2-in.
Furnace
21-in. Furnace
up to 5-Ton AC
Capacity
Up to 5-Ton AC
capacity airflow
24-1/2-in. Furnace
up to 4-Ton AC
Capacity
20- or 24-in. Media
Cabinet
45°
Bottom Return Plenum
Transition
20- or 24-in. Media Cabinet
20- or -24-in. Media Cabinet Installation
for Combination Side and Bottom Return
20- or -24-in. Media Cabinet Installation
with Angled Transition
14-3/16-in. Furnace
14-3/16-in. Furnace
Screws
Screw
Screw
Filler plates
Filler plate
14--3/16-in. Furnace with Filler Plates, Off--Set to Right
14--3/16-in. Furnace with Filler Plates, Centered
A11437
Fig. 17 -- Media Filter
22
FURNACE
(OR COIL CASING
WHEN USED)
FURNACE
APPROVED
COIL ASSEMBLY
OR
COIL BOX
COMBUSTIBLE
FLOORING
COMBUSTIBLE
FLOORING
A
PLENUM
OPENING
D
DOWNFLOW
SUBBASE
FLOOR
OPENING
SHEET METAL
PLENUM
SHEET METAL
PLENUM
FLOOR
OPENING
C
FLOOR
OPENING
A10491
Fig. 18 -- Installation on Combustible Flooring
Table 6 – Opening Dimensions -- In. (mm)
FURNACE
CASING
WIDTH
IN. (mm)
17–1/2
(445)
21
(533)
24---1/2
(622)
PLENUM OPENING
APPLICATION
Upflow Applications on Combustible or Noncombustible Flooring (KGASB subbase not required)
Downflow Applications on Noncombustible Flooring (KGASB
subbase not required)
Downflow applications on combustible flooring (KGASB subbase required)
Downflow Applications on Combustible Flooring with CNPV,
CNRV, CAR or CAP Coil Assembly or KCAKC coil box (KGASB
subbase not required)
Upflow Applications on Combustible or Noncombustible Flooring (KGASB subbase not required)
Downflow Applications on Noncombustible Flooring (KGASB
subbase not required)
Downflow applications on combustible flooring (KGASB subbase required)
Downflow Applications on Combustible Flooring with CNPV,
CNRV, CAR or CAP Coil Assembly or KCAKC coil box (KGASB
subbase not required)
Upflow Applications on Combustible or Noncombustible Flooring (KGASB subbase not required)
Downflow Applications on Noncombustible Flooring (KGASB
subbase not required)
Downflow applications on Combustible flooring (KGASB subbase required)
Downflow Applications on Combustible Flooring with CNPV,
CNRV, CAR or CAP Coil Assembly or KCAKC coil box (KGASB
subbase not required)
23
FLOOR OPENING
A
B
C
D
16
(406)
15--- 7/8
(403)
15--- 1/8
(384)
21--- 5/8
(549)
19
(483)
19
(483)
16--- 5/8
(422)
16--- 1/2
(419)
16--- 3/4
(425)
22--- 1/4
(565)
19--- 5/8
(498)
20--- 5/8
(600)
15--- 1/2
(394)
19
(483)
16--- 1/2
(419)
20
(508)
19--- 1/2
(495)
19--- 3/8
(492)
18--- 5/8
(473)
21--- 5/8
(549)
19
(483)
19
(483)
20--- 1/8
(511)
20
(508)
20--- 1/4
(514)
22--- 1/4
(565)
19--- 5/8
(498)
20--- 5/8
(600)
19
(483)
19
(483)
20
(508)
20
(508)
23
(584)
22--- 7/8
(581)
22--- 1/8
(562)
21--- 1/8
(537)
19
(483)
19
(483)
23--- 5/8
(600)
23--- 1/2
(597)
23--- 3/4
(603)
22--- 1/4
(565)
19--- 5/8
(498)
20--- 5/8
(600)
22--- 1/2
(572)
19
(483)
23--- 1/2
(597)
20
(508)
59MN7A
B
UPFLOW
PERFORATED
DISCHARGE DUCT
FLANGE
DOWNFLOW
HORIZONTAL
90°
90°
YES
YES
YES
120°
MIN
YES
120°
MIN
YES
120°
MIN
NO
NO
59MN7A
YES
NO
A10493
Fig. 19 -- Duct Flanges
5/ 16″
(8mm)
(8mm)
5/ 16″
1 3/4″
(44mm)
1 3/4″
(44mm)
(8mm)
5/16″
BOTTOM
CLOSURE
PANEL
(8mm)
5/ 16″
(44mm) 1 3/ 4″
3/
(44mm) 1 4″
BOTTOM PLATE
A89014
A11092
Fig. 20 -- Leveling Legs
Fig. 21 -- Removing Bottom Closure Panel
LEVEL 0-IN. (0 MM) TO
1/2-IN. (13 MM) MAX
MIN 1/4-IN. (6 MM) TO
1/2-IN. (13 MM) MAX
UPFLOW OR
DOWNFLOW
HORIZONTAL
A11237
Fig. 22 -- Furnace Pitch Requirements
24
A11036
A11037
Fig. 23 -- Upflow Return Air Configurations and Restrictions
Fig. 24 -- Downflow Return Air Configurations
and Restrictions
HORIZONTAL TOP
RETURN NOT
PERMITTED FOR
ANY MODEL
A11038
Fig. 25 -- Horizontal Return Air Configurations
and Restrictions
25
59MN7A
ANY COMBINATION OF 1, 2, OR 3 PERMITTED.
COMBUSTION - AIR PIPE
(SEE VENTING SECTION)
30 IN. (762 mm)
MIN. WORK AREA
59MN7A
2-IN.
(51 mm)
ROLLOUT PROTECTION REQUIRED
Install 12” x 22” (305 x 559 mm) sheet
metal in front of burner compartment
area.
A11154
Fig. 26 -- Working Platform for Attic Installation
NOTE: Local codes may require a drain pan and condensate trap when a condensing furnace is installed over a finished ceiling.
COMBUSTION-AIR PIPE
(SEE VENTING SECTION)
2-IN.
(51 mm)
A11155
Fig. 27 -- Suspended Furnace Installation
NOTE: Local codes may require a drain pan and condensate trap when a condensing furnace is installed over a finished ceiling.
26
General Requirements
The duct system should be designed and sized according to
accepted national standards such as those published by: Air
Conditioning Contractors Association (ACCA), Sheet Metal and
Air Conditioning Contractors National Association (SMACNA) or
American Society of Heating, Refrigerating and Air Conditioning
Engineers (ASHRAE) or consult The Air Systems Design
Guidelines reference tables available from your local distributor.
The duct system should be sized to handle the required system
design CFM at the design external static pressure. The furnace
airflow rates are provided in Table 7--Air Delivery--CFM (With
Filter). When a furnace is installed so that the supply ducts carry air
circulated by the furnace to areas outside the space containing the
furnace, the return air shall also be handled by duct(s) sealed to the
furnace casing and terminating outside the space containing the
furnace.
Secure ductwork with proper fasteners for type of ductwork used.
Seal supply-- and return--duct connections to furnace with code
approved tape or duct sealer.
NOTE: Flexible connections should be used between ductwork
and furnace to prevent transmission of vibration.
Ductwork passing through unconditioned space should be
insulated to enhance system performance. When air conditioning is
used, a vapor barrier is recommended.
Maintain a 1--in. (25 mm) clearance from combustible materials to
supply air ductwork for a distance of 36--in. (914 mm) horizontally
from the furnace. See NFPA 90B or local code for further
requirements.
Ductwork Acoustical Treatment
NOTE: Metal duct systems that do not have a 90 degree elbow
and 10 ft. (3 M) of main duct to the first branch take--off may
require internal acoustical lining. As an alternative, fibrous
ductwork may be used if constructed and installed in accordance
with the latest edition of SMACNA construction standard on
fibrous glass ducts. Both acoustical lining and fibrous ductwork
shall comply with NFPA 90B as tested by UL Standard 181 for
Class 1 Rigid air ducts.
NOTE: For horizontal applications, the top most flange may be
bent past 90_ to allow the evaporator coil to hang on the flange
temporarily while the remaining attachment and sealing of the coil
are performed.
27
59MN7A
AIR DUCTS
Table 7 – Cooling4 and Heating Air Delivery -- CFM (Bottom Return5 With Filter)
Unit Size
(SW1-5 and SW4-3 set to OFF, except as indicated. See notes 1 and 2)
Clg/CF Switch Settings
External Static Pressure (ESP)
SWx-3
SWx-2
SWx-1
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1035
1025
1010
880
870
855
1050
1035
1025
1010
1250
1230
1190
1155
1115
1255
1250
1230
1190
1155
1115
1255
1255
1250
1230
1190
1155
1115
1405
1370
1335
1300
1260
1225
1190
1155
1085
1095
1095
1090
1080
1065
1050
1035
1020
535
515
505
515
495
420
410
415
0.1
0.2
0.3
060-14
Clg Default:
OFF
OFF
OFF
1060
1070
1080
1080
1075
CF Default:
OFF
OFF
OFF
545
530
520
525
510
See note 4
OFF
OFF
ON
545
530
520
525
510
See note 4
OFF
ON
OFF
710
710
710
695
690
See note 4
OFF
ON
ON
875
880
890
895
895
890
885
ON
OFF
OFF
1060
1070
1080
1080
1075
1065
ON
OFF
ON
1235
1240
1250
1255
1255
ON
ON
OFF
1235
1240
1250
1255
ON
ON
ON
1235
1240
1250
Maximum Clg Airflow 2
1425
1425
Maximum Heat Airflow 3
1075
Intermediate Heat Airflow 3
Minimum Heat Airflow 3
Clg/CF Switch Settings
SWx-3
SWx-2
SWx-1
Cooling (SW2)
59MN7A
Cont Fan (SW3)
Clg SW2:
Heating
(SW1)
Unit Size
1065
1050
See note 4
400
380
See note 4
External Static Pressure (ESP)
0.4
0.5
0.6
0.7
0.8
0.9
060---20
Clg Default:
OFF
OFF
OFF
1735
1735
1725
1715
1700
CF Default:
OFF
OFF
OFF
545
530
520
525
510
See note 4
OFF
OFF
ON
540
525
525
520
540
See note 4
OFF
ON
OFF
680
725
725
720
720
See note 4
OFF
ON
ON
925
915
910
895
900
890
875
ON
OFF
OFF
1070
1075
1080
1070
1080
1075
ON
OFF
ON
1215
1245
1235
1220
1220
ON
ON
OFF
1380
1385
1395
1390
ON
ON
ON
1735
1735
1725
Maximum Clg Airflow 2
1955
1950
Maximum Heat Airflow 3
1080
Intermediate Heat Airflow 3
Minimum Heat Airflow 3
Cooling (SW2)
Cont Fan (SW3)
Clg SW2:
Heating
(SW1)
1625
1605
865
860
855
1055
1045
1030
1020
1210
1200
1195
1185
1175
1395
1390
1380
1365
1355
1340
1715
1700
1685
1665
1650
1625
1605
1940
1925
1905
1885
1855
1815
1745
1685
1085
1095
1090
1095
1085
1070
1055
1045
1030
685
725
730
725
730
See note 4
560
555
555
550
565
See note 4
NOTE: See notes at end of table.
28
1685
1665
1650
1.0
Unit Size
Clg/CF Switch Settings
SWx-3
SWx-2
SWx-1
0.1
0.2
0.3
External Static Pressure (ESP)
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1035
1025
1005
875
860
845
1045
1035
1025
1005
1255
1250
1235
1220
1185
1260
1255
1250
1235
1220
1185
1255
1260
1255
1250
1235
1220
1185
1450
1415
1375
1335
1300
1265
1225
1190
1485
1450
1415
1375
1335
1300
1265
1225
1190
755
745
755
755
765
620
625
630
0.1
0.2
0.3
080-14
Clg Default:
OFF
OFF
OFF
1055
1065
1080
1075
1065
CF Default:
OFF
OFF
OFF
520
505
505
495
490
See note 4
OFF
OFF
ON
520
505
505
495
490
See note 4
OFF
ON
OFF
665
685
680
660
665
See note 4
OFF
ON
ON
885
895
905
900
900
895
885
ON
OFF
OFF
1055
1065
1080
1075
1065
1050
ON
OFF
ON
1245
1245
1255
1255
1260
ON
ON
OFF
1245
1245
1255
1255
ON
ON
ON
1245
1245
1255
Maximum Clg Airflow 2
1520
1485
Maximum Heat Airflow 3
1520
Intermediate Heat Airflow 3
Minimum Heat Airflow 3
Clg/CF Switch Settings
SWx-3
SWx-2
SWx-1
Cooling (SW2)
Cont Fan (SW3)
Clg SW2:
Heating
(SW1)
Unit Size
1050
1045
See note 4
620
610
See note 4
External Static Pressure (ESP)
0.4
0.5
0.6
0.7
0.8
0.9
080---20
Clg Default:
OFF
OFF
OFF
1745
1755
1755
1760
1755
CF Default:
OFF
OFF
OFF
700
710
750
725
750
See note 4
OFF
OFF
ON
700
710
750
725
750
See note 4
OFF
ON
OFF
830
860
870
890
960
See note 4
OFF
ON
ON
1045
1045
1060
1070
1070
1070
1095
ON
OFF
OFF
1215
1220
1245
1240
1235
1235
ON
OFF
ON
1370
1370
1390
1390
1400
ON
ON
OFF
1745
1755
1755
1760
ON
ON
ON
1745
1755
1755
Maximum Clg Airflow 2
1920
1920
Maximum Heat Airflow 3
1340
Intermediate Heat Airflow 3
Minimum Heat Airflow 3
Cooling (SW2)
Cont Fan (SW3)
Clg SW2:
Heating
(SW1)
1705
1685
1090
1080
1070
1225
1220
1235
1235
1395
1400
1390
1390
1385
1755
1750
1745
1725
1705
1685
1760
1755
1750
1745
1725
1705
1685
1945
1945
1945
1960
1950
1940
1915
1900
1355
1370
1385
1380
1385
1400
1400
1385
1380
780
810
835
840
845
See note 4
595
595
600
595
605
See note 4
NOTE: See notes at end of table.
29
1750
1745
1725
1.0
59MN7A
Table 7 -- Cooling4 and Heating Air Delivery -- CFM (Bottom Return5 With Filter) (Continued)
Table 7 -- Cooling4 and Heating Air Delivery -- CFM (Bottom Return5 With Filter) (Continued)
Unit Size
0.1
0.2
0.3
External Static Pressure (ESP)
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1805
1780
1770
1080
1065
1070
1295
1300
1290
1285
1485
1480
1485
1475
1460
1840
1835
1825
1805
1780
1770
2135
2140
2130
2115
2100
2070
2015
2175
2170
2160
2150
2135
2120
2065
2020
1575
1595
1595
1600
1605
1600
1600
1590
1575
950
955
965
975
970
755
745
750
0.1
0.2
0.3
100-22
Clg Default:
OFF
OFF
OFF
1820
1825
1840
1845
1840
CF Default:
OFF
OFF
OFF
750
740
745
730
715
See note 4
OFF
OFF
ON
750
740
745
730
715
See note 4
OFF
ON
OFF
900
900
915
910
905
See note 4
OFF
ON
ON
1070
1075
1095
1095
1090
1085
1095
ON
OFF
OFF
1280
1285
1305
1305
1310
1305
ON
OFF
ON
1440
1445
1465
1465
1470
ON
ON
OFF
1820
1825
1840
1845
ON
ON
ON
2135
2140
2140
Maximum Clg Airflow 2
2160
2165
Maximum Heat Airflow 3
1570
Intermediate Heat Airflow 3
Minimum Heat Airflow 3
Clg/CF Switch Settings
SWx-3
SWx-2
SWx-1
Cooling (SW2)
Cont Fan (SW3)
59MN7A
Clg/CF Switch Settings
SWx-3
SWx-2
SWx-1
Clg SW2:
Heating
(SW1)
Unit Size
735
720
See note 4
External Static Pressure (ESP)
0.4
0.5
0.6
0.7
0.8
0.9
OFF
OFF
1850
1855
1860
1855
1850
CF Default:
OFF
OFF
OFF
930
925
915
900
885
See note 4
OFF
OFF
ON
765
745
740
705
680
See note 4
OFF
ON
OFF
930
925
915
900
885
See note 4
OFF
ON
ON
1095
1100
1110
1105
1085
See note 4
ON
OFF
OFF
1265
1255
1265
1280
1275
1285
1270
ON
OFF
ON
1465
1455
1470
1465
1465
1470
ON
ON
OFF
1850
1855
1860
1855
1850
ON
ON
ON
2200
2200
2200
2190
Maximum Clg Airflow 2
2200
2200
2200
Maximum Heat Airflow 3
1815
1820
Intermediate Heat Airflow 3
1095
Minimum Heat Airflow 3
905
Clg SW2:
Heating
(SW1)
5.
6.
1830
1805
1775
1.0
1750
1730
1260
1250
1230
1455
1450
1435
1415
1830
1805
1775
1750
1730
2185
2170
2145
2085
1990
1890
2190
2185
2170
2145
2085
1990
1890
1825
1820
1815
1795
1775
1745
1720
1700
1100
1110
1105
1085
See note 4
900
890
875
855
See note 4
1. Nominal 350 CFM/ton cooling airflow is delivered with SW1--5 and SW4--3 set to OFF.
4.
See note 4
OFF
Cont Fan (SW3)
3.
1825
120-22
Clg Default:
Cooling (SW2)
2.
1835
Set SW1--5 to ON for nominal 400 CFM/ton (+15% airflow).
Set SW4--3 to ON for nominal 325 CFM/ton (--7% airflow).
Set both SW1--5 and SW4--3 to ON for nominal 370 CFM/ton (+7% airflow).
The above adjustments in airflow are subject to motor horsepower range/capacity.
Maximum cooling airflow is achieved when switches SW2--1, SW2--2, SW2--3 and SW1--5 are set to ON, and SW4--3 is set to OFF.
All heating CFM’s are when low/medium heat rise adjustment switch (SW1--3) and comfort/efficiency adjustment switch (SW1--4) are both
set to OFF
Ductwork must be sized for high--heating CFM within the operational range of ESP. Operation within the blank areas of the chart is not
recommended because high--heat operation will be above 1.0 ESP.
All airflows on 21” casing size furnaces are 5% less on side return only installations.
Side returns for 24.5” casing sizes require two sides, or side and bottom, to allow sufficient airflow at the return of the furnace.
30
GAS PIPING
WARNING
FIRE OR EXPLOSION HAZARD
A failure to follow this warning could result in personal
injury, death, and/or property damage.
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
If local codes allow the use of a flexible gas appliance
connector, always use a new listed connector. Do not use a
connector which has previously served another gas
appliance. Black iron pipe shall be installed at the furnace
gas control valve and extend a minimum of 2--in. (51 mm)
outside the furnace.
Never purge a gas line into a combustion chamber. Never
test for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection
of leaks to check all connections. A fire or explosion may
result causing property damage, personal injury or loss of
life.
!
WARNING
!
WARNING
CAUTION
FURNACE DAMAGE HAZARD
FIRE OR EXPLOSION HAZARD
Failure to follow this caution may result in furnace damage.
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Connect gas pipe to furnace using a backup wrench to
avoid damaging gas controls and burner misalignment.
Use proper length of pipe to avoid stress on gas control
manifold and gas valve.
!
WARNING
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Gas valve inlet and/or inlet pipe must remain capped until
gas supply line is permanently installed to protect the valve
from moisture and debris. Also, install a sediment trap in the
gas supply piping at the inlet to the gas valve.
Gas piping must be installed in accordance with national and local
codes. Refer to current edition of NFGC in the U.S.A. Refer to
current edition of NSCNGPIC in Canada.
Installations must be made in accordance with all authorities
having jurisdiction. If possible, the gas supply line should be a
separate line running directly from meter to furnace.
NOTE: Use a back--up wrench on the inlet of the gas valve when
connecting the gas line to the gas valve.
NOTE: In the state of Massachusetts:
1. Gas supply connections MUST be performed by a licensed
plumber or gas fitter.
2. When flexible connectors are used, the maximum length
shall not exceed 36 in. (915 mm).
3. When lever handle type manual equipment shutoff valves
are used, they shall be T--handle valves.
4. The use of copper tubing for gas piping is NOT approved
by the state of Massachusetts.
Refer to Table 8 for recommended gas pipe sizing. Risers must be
used to connect to furnace and to meter. Support all gas piping
with appropriate straps, hangers, etc. Use a minimum of 1 hanger
every 6 ft. (1.8 M). Joint compound (pipe dope) should be applied
sparingly and only to male threads of joints. Pipe dope must be
resistant to the action of propane gas.
An accessible manual equipment shutoff valve MUST be installed
external to furnace casing and within 6 ft. (1.8 M) of furnace.
Install a sediment trap in riser leading to furnace as shown in Fig.
29. Connect a capped nipple into lower end of tee. Capped nipple
should extend below level of furnace gas controls. Place a ground
joint union between furnace gas control valve and exterior manual
equipment gas shutoff valve.
A 1/8--in. (3 mm) NPT plugged tapping, accessible for test gauge
connection, MUST be installed immediately upstream of gas
supply connection to furnace and downstream of manual
equipment shutoff valve.
Piping should be pressure and leak tested in accordance with the
current addition of the NFGC in the United States, local, and
national plumbing and gas codes before the furnace has been
connected. Refer to current edition of NSCNGPIC in Canada.
After all connections have been made, purge lines and check for
leakage at furnace prior to operating furnace.
NOTE:
The furnace gas control valve inlet pressure tap
connection is suitable to use as test gauge connection providing
test pressure DOES NOT exceed maximum 0.5 psig (14--In. W.C.)
stated on gas control valve. (See Fig. 50.)
If pressure exceeds 0.5 psig (14--In. W.C.), gas supply pipe must be
disconnected from furnace and capped before and during supply
pipe pressure test. If test pressure is equal to or less than 0.5 psig
(14--In. W.C.), turn off electric shutoff switch located on furnace
gas control valve and accessible manual equipment shutoff valve
before and during supply pipe pressure test. After all connections
have been made, purge lines and check for leakage at furnace prior
to operating furnace.
The gas supply pressure shall be within the maximum and
minimum inlet supply pressures marked on the rating plate with
the furnace burners ON and OFF.
Some installations require gas entry on right side of furnace (as
viewed in upflow). (See Fig. 28.)
Gas Pipe Grommet
For direct vent (2-pipe) applications, the knockout for the gas pipe
must be sealed to prevent air leakage. Remove the knockout, install
the grommet in the knockout, then insert the gas pipe. The
grommet is included in the loose parts bag. See Fig. 28.
31
59MN7A
!
!
Table 8 – Maximum Capacity of Pipe
NOMINAL
IRON PIPE
SIZE
IN. (MM)
1/2 (13)
3/4 (19)
1 ( 25)
1-1/4 (32)
1-1/2 (39)
Field--supplied wiring shall conform with the limitations of 63_F
(33_C) rise.
LENGTH OF PIPE --- FT (M)
10
(3.0)
20
(6.0)
30
(9.1)
40
(12.1)
50
(15.2)
175
360
680
1400
2100
120
250
465
950
1460
97
200
375
770
1180
82
170
320
660
990
73
151
285
580
900
!
ELECTRICAL SHOCK AND FIRE HAZARD
Failure to follow this warning could result in personal
injury, death, or property damage.
The cabinet MUST have an uninterrupted or unbroken
ground according to NEC ANSI/NFPA 70--2011 or local
codes to minimize personal injury if an electrical fault
should occur. In Canada, refer to Canadian Electrical Code
CSA C22.1. This may consist of electrical wire, conduit
approved for electrical ground or a listed, grounded power
cord (where permitted by local code) when installed in
accordance with existing electrical codes. Refer to the
power cord manufacturer’s ratings for proper wire gauge.
Do not use gas piping as an electrical ground.
* Cubic ft of gas per hr for gas pressures of 0.5 psig (14--- In. W.C.) or less and
a pressure drop of 0.5--- In. W.C. (based on a 0.60 specific gravity gas). Ref:
Table 8 above and 6.2 of NFPA54/ANSI Z223.1--- 2009.
Gas Pipe Grommet Required
For Direct Vent Applications
59MN7A
Left Side Gas Entry. Gas Pipe
Grommet Required For Direct
Vent Applications.
WARNING
!
CAUTION
FURNACE MAY NOT OPERATE HAZARD
Failure to follow this caution may result in intermittent
furnace operation.
A11338
Furnace control must be grounded for proper operation or
else control will lock out. Control must remain grounded
through green/yellow wire routed to gas valve and manifold
bracket screw.
Fig. 28 -- Gas Entry
GAS
SUPPLY
115--V Wiring
FRONT
MANUAL
SHUT OFF
VALVE
(REQUIRED)
UNION
SEDIMENT
TRAP
NOTE: Union may be inside the
vestibule where permitted by
local codes.
A11035
Fig. 29 -- Typical Gas Pipe Arrangement
ELECTRICAL CONNECTIONS
!
Furnace must have a 115-v power supply properly connected and
grounded.
NOTE: Proper polarity must be maintained for 115-v wiring. If
polarity is incorrect, control LED status indicator light will flash
rapidly and furnace will NOT operate.
Verify that the voltage, frequency, and phase correspond to that
specified on unit rating plate. Also, check to be sure that service
provided by utility is sufficient to handle load imposed by this
equipment. Refer to rating plate or Table 9 for equipment electrical
specifications.
U.S.A. Installations: Make all electrical connections in accordance
with the current edition of the National Electrical Code (NEC)
ANSI/NFPA 70 and any local codes or ordinances that might
apply.
Canada Installations: Make all electrical connections in
accordance with the current edition of the Canadian Electrical
Code CSA C22.1 and any local codes or ordinances that might
apply.
!
WARNING
WARNING
ELECTRICAL SHOCK HAZARD
FIRE HAZARD
Failure to follow this warning could result in personal
injury or death.
Failure to follow this warning could result in personal
injury, death, or property damage.
Blower door switch opens 115--v power to control. No
component operation can occur. Do not bypass or close
switch with blower door removed.
Do not connect aluminum wire between disconnect
switch and furnace. Use only copper wire. See Fig. 31.
See Fig. 33 for field wiring diagram showing typical field 115--v
wiring. Check all factory and field electrical connections for
tightness.
Use a separate, fused branch electrical circuit with a properly sized
fuse or circuit breaker for this furnace. See Table 9 for wire size
and fuse specifications. A readily accessible means of electrical
disconnect must be located within sight of the furnace.
32
J--Box Installation
WARNING
FIRE OR ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury, death, or property damage.
If field--supplied manual disconnect switch is to be mounted
on furnace casing side, select a location where a drill or
fastener cannot damage electrical or gas components.
The J-Box is used when field line voltage electrical connections are
made to the furnace wiring harness inside the furnace casing. The
J-Box is not required if a field-supplied electrical box is attached to
the outside of the furnace casing and the box is grounded to the
green ground wire of the main wiring harness and the earth ground
of the field electrical supply.
The J--Box cover, mounting bracket and screws are shipped in the
loose parts bag included with the furnace. The J--Box can be
mounted on the left or right side of the casing, as viewed from the
upflow position.
Remove the J--Box cover and mounting bracket from the loose
parts bag. Select a 7/8--in. (22 mm) knock-out on the desired side
of the casing. Remove the knock-out from the casing. Drill two (2)
1/8--in. (3 mm) pilot holes in the casing dimples by the desired
7/8--in. (22 mm) knock-out.
Align the J--box mounting bracket against the inside of the casing
and secure the mounting bracket with the screws. (See Fig. 30.)
BX Cable Installation in Furnace J-- Box
1. Install J--Box mounting bracket to inside of furnace casing.
See Fig. 30.
2. Route BX connector through 7/8--in. (22 mm) diameter
hole in casing and J--Box bracket.
3. Secure BX cable to J--Box bracket with connectors approved for the type of cable used.
4. Connect field ground wire and factory ground wire to green
ground screw on J--Box mounting bracket as shown in Fig.
30.
5. Connect field power and neutral leads to furnace power
leads. as shown in Fig. 33.
6. Attach furnace J--Box cover to mounting bracket with
screws supplied in loose parts bag. Do not pinch wires
between cover and bracket.
Electrical Box on Furnace Casing Side
24--V Wiring
NOTE: Check that duct on side of furnace will not interfere with
installed electrical box.
1. Fasten a field-supplied external electrical box to the outside
of the casing by driving two field-supplied screws from inside electrical box into casing. (See Fig. 31.)
2. Route field power wiring into external electrical box.
3. Pull furnace power wires through 1/2-in. (12 mm) diameter
hole in J-Box. If necessary, loosen power wires from strain-relief wire-tie on furnace wiring harness.
4. Connect any code required external disconnect(s) to field
power wiring.
5. Route external field power wires through holes in electrical
box and casing.
6. Connect field ground wire and factory ground wire to green
ground screw on J--Box mounting bracket as shown in Fig.
30.
7. Connect field power and neutral leads to furnace power
leads as shown in Fig. 33.
8. Attach furnace J-Box cover to mounting bracket with
screws supplied in loose parts bag. Do not pinch wires
between cover and bracket.
9. Complete external disconnect wiring and installation. Connect line voltage leads as shown in Fig. 31. Use best practices (NEC in U.S.A. for wire bushings, strain relief, etc.,
CANADA: Canadian Electrical Code CSA C22.1)
Make field 24--v connections at the 24--v terminal strip. (See Fig.
34.) Connect terminal Y/Y2 as shown in Fig. 33 for proper cooling
operation. Use only AWG No. 18, color--coded, copper thermostat
wire.
NOTE: Use AWG No. 18 color-coded copper thermostat wire for
lengths up to 100 ft. (30.5 M). For wire lengths over 100 ft., use
AWG No. 16 wire.
The 24--v circuit contains an automotive--type, 3--amp. fuse located
on the control. Any direct shorts during installation, service, or
maintenance could cause this fuse to blow. If fuse replacement is
required, use ONLY a 3--amp. fuse of identical size. See Fig. 34.
Power Cord Installation in Furnace J-- Box
NOTE: Power cords must be able to handle the electrical
requirements listed in Table 9. Refer to power cord manufacturer’s
listings.
1. Install J--Box mounting bracket to inside of furnace casing.
(See Fig. 30.)
2. Route listed power cord through 7/8--in. (22 mm) diameter
hole in casing and J--Box bracket.
Thermostats
For best results, use a communicating wall control to control this
modulating furnace. A single stage or two--stage heating and
cooling thermostat can be used with the furnace. The furnace
control board CPU will control the furnace and outdoor unit
staging. A two stage heating and cooling thermostat can also be
used to control the staging. However, full modulating capability
will not be available when the furnace staging is controlled by the
thermostat. Furnace staging will be limited to Minimum and
Maximum inputs or Intermediate and Maximum inputs depending
on the configuration of set-up switches SW1-2 and SW4-2. For
two stage thermostat control of a 2-stage outdoor unit, remove the
ACRDJ jumper from the furnace control board. Refer to typical
thermostat wiring diagrams and the Sequence of Operation section
for additional details. Consult the thermostat installation
instructions for specific information about configuring the
thermostat. See Fig. 34 and 35.
Accessories (See Fig. 32 and 34.)
1. Electronic Air Cleaner (EAC)
Connect an accessory Electronic Air Cleaner (if used) using
1/4--in. female quick connect terminals to the two male
1/4--in. quick--connect terminals on the control board
marked EAC--1 and EAC--2. The terminals are rated for
115VAC, 1.0 amps maximum and are energized during
blower motor operation.
33
59MN7A
!
3. Secure power cord to J--Box bracket with a strain relief
bushing or a connector approved for the type of cord used.
4. Pull furnace power wires through 1/2--in. (12 mm) diameter
hole in J--Box. If necessary, loosen power wires from
strain—relief wire--tie on furnace wiring harness.
5. Connect field ground wire and factory ground wire to green
ground screw on J--Box mounting bracket as shown in Fig.
30.
6. Connect power cord power and neutral leads to furnace
power leads as shown in Fig. 33.
7. Attach furnace J--Box cover to mounting bracket with
screws supplied in loose parts bag. Do not pinch wires
between cover and bracket. (See Fig. 30).
59MN7A
2. Humidifier (HUM)
The HUM terminal is a 24 VAC output, energized when the blower
is operating during a call for heat.
Connect an accessory 24 VAC, 0.5 amp. maximum humidifier (if
used) to the ¼--in. male quick--connect HUM terminal and
COM--24V screw terminal on the control board thermostat strip.
NOTE: If the humidifier has its own 24 VAC power supply, an
isolation relay may be required. Connect the 24 VAC coil of the
isolation relay to the HUM and COM/24V screw terminal on the
control board thermostat strip. (See Fig. 32.)
3. Communication Connector (communication connection)
This connection is used when the furnace is controlled by
an optional communicating User Interface instead of a
standard thermostat. The communication plug is supplied
with the User Interface. Refer to the instructions supplied
with the User Interface for complete details. See Fig. 34.
4. Outside Air Thermistor (OAT)
The OAT connection is used in conjunction with communicating User Interface. It is not required when the furnace
is controlled by a standard type thermostat. Refer to the instructions supplied with the User Interface for complete details.
Alternate Power Supplies
This furnace is designed to operate on utility generated power
which has a smooth sinusoidal waveform. If the furnace is to be
operated on a generator or other alternate power supply, the
alternate power supply must produce a smooth sinusoidal
waveform for compatibility with the furnace electronics. The
alternate power supply must generate the same voltage, phase, and
frequency (Hz) as shown in Table 9 or the furnace rating plate.
Power from an alternate power supply that is non-sinusoidal may
damage the furnace electronics or cause erratic operation.
Contact the alternate power supply manufacturer for specifications
and details.
Table 9 – Electrical Data
UNIT SIZE
060---14
060---20
080---14
080---20
100---22
120---22
VOLTS--HERTZ--PHASE
115--- 60--- 1
115--- 60--- 1
115--- 60--- 1
115--- 60--- 1
115--- 60--- 1
115--- 60--- 1
OPERATING VOLTAGE
RANGE*
Maximum*
Minimum*
127
127
127
127
127
127
104
104
104
104
104
104
MODULATING
MAXIMUM
UNIT
UNIT
AMPACITY#
AMPS
9.7
14.8
9.7
14.8
14.8
14.8
12.7
19.1
12.7
19.1
19.1
19.1
MINIMUM
WIRE
SIZE
AWG
14
12
14
12
12
12
MAXIMUM
WIRE
LENGTH
FT (M)}
29 (8.8)
30 (9.1)
29 (8.8)
30 (9.1)
30 (9.1)
30 (9.1)
MAXIMUM
FUSE OR CKT
BKR
AMPS{
15
20
15
20
20
20
* Permissible limits of the voltage range at which the unit operates satisfactorily.
# Unit ampacity = 125 percent of largest operating component’s full load amps plus 100 percent of all other potential operating components’ (EAC, humidifier,
etc.) full load amps.
{Time ---delay type is recommended.
}Length shown is as measured one way along wire path between furnace and service panel for maximum 2 percent voltage drop.
34
GROUND
NEUTRAL
59MN7A
LINE VOLTAGE
J BOX LOCATIONS
J−BOX
MOUNTING
SCREWS
J−BOX
MOUNTING
BRACKET
GROUND
SCREW
ELECTRIC
DISCONNECT
SWITCH
J−BOX COVER
COPPER
WIRE ONLY
ALUMINUM
WIRE
A11156
A11146
Fig. 30 -- Installing J--Box (When Used)
(Appearance May Vary)
Fig. 31 -- Field--Supplied Electrical Box on Furnace Casing
35
To HUM Terminal On
To Humidifier Leads
Furnace Control Board
24 V
Coil
To Humidifier Leads
To Com/24V Screw Terminal
on Thermostat Strip
A11157
59MN7A
Fig. 32 -- Field--supplied Isolation Relay for Humidifiers with Internal Power Supply
FIELD 24-VOLT WIRING
FIELD 115-, 208/230-, 460-VOLT WIRING
FACTORY 24-VOLT WIRING
FACTORY 115-VOLT WIRING
NOTE 2
W
FIVE
WIRE
BLOWER
DOOR
SWITCH
C
Y
R
G
1-STAGE
THERMOSTAT
TERMINALS
FIELD-SUPPLIED
FUSED DISCONNECT
THREE-WIRE
HEATINGONLY
BLK
BLK
WHT
WHT
GND
115-VOLT FIELD- JUNCTION
SUPPLIED
BOX
FUSED
DISCONNECT
C
O
N
T
R
O
L
208/230- OR
460-VOLT
THREE
PHASE
W2
COM
W/W1
Y/Y2
NOTE 1
R
GND
CONDENSING
UNIT
G
24-VOLT
TERMINAL
BLOCK
FURNACE
208/230VOLT
SINGLE
PHASE
NOTES: 1. Connect Y/Y2-terminal as shown for proper operation.
2. Some thermostats require a "C" terminal connection as shown.
3. If any of the original wire, as supplied, must be replaced, use
same type or equivalent wire.
A11401
Fig. 33 -- Typical Field Wiring Diagram
36
COMMUNICATION
CONNECTOR
MODEL PLUG
CONNECTOR
CONTINUOUS FAN
(CF) AIRFLOW
SETUP SWITCHES
OUTDOOR
AIR TEMP
CONNECTOR
SW4 SETUP
SWITCHES
PL8 - MODULATING
GAS VALVE
CONNECTOR
SW1 SETUP
SWITCHES AND
BLOWER OFFDELAY
AIR CONDITIONING
(A/C) AIRFLOW
SETUP SWITCHES
ACRDJ – AIR
CONDITIONING
RELAY DISABLE
JUMPER
24-V THERMOSTAT
TERMINALS
FLASH
UPGRADE
CONNECTOR
(FACTORY
ONLY)
STATUS AND COMM
LED LIGHTS
PL3 – ECM BLOWER
HARNESS
CONNECTOR
3-AMP FUSE
TRANSFORMER 24-VAC
CONNECTIONS
115-VAC (L2) NEUTRAL
CONNECTIONS
PART NUMBER AND
DATE CODE WWYY
PL1 – LOW VOLTAGE MAIN
HARNESS CONNECTOR
SOFTWARE
VERSION
EAC-1 TERMINAL
(115-VAC 1.0 AMP MAX.)
115-VAC (L1) LINE
VOLTAGE CONNECTIONS
PL2 – HOT SURFACE
IGNITER & INDUCER
MOTOR CONNECTOR
A11616
Fig. 34 -- Example of Modulating Furnace Control
37
59MN7A
HUMIDIFIER
TERMINAL (24-VAC
0.5 AMP MAX.
THERMOSTAT
THERMOSTAT
D
59MN7A
D
11, and 16
15, and 16
Modulating and 2-Stage Furnace with Single-Speed Heat Pump
Modulating and 2-Stage Furnace with Single-Speed Air Conditioner
THERMOSTAT
THERMOSTAT
D
D
15, and 16
12 and 16
Modulating and 2-Stage Furnace with Two-Speed Air Conditioner
Modulating and 2-Stage Furnace with Two-Speed Heat Pump
A11274
Fig. 35 -- Thermostat Wiring Diagrams
38
1. Heat pump MUST have a high pressure switch for dual fuel applications.
2. Refer to outdoor equipment Installation Instructions for additional information and setup procedure.
3. If the heat pump date code is 1501E or earlier, select the “ZONE” position on the two speed heat pump control. Heat pumps with date
code 1601E and later do not have or require a “ZONE” selection.
4. Outdoor Air Temperature - sensor must be attached in all dual fuel applications.
5. Configure the thermostat for air conditioner installations. Refer to thermostat instructions.
6. Configure thermostat for heat pump installations. Refer to thermostat instructions.
7. Configure thermostat for single-stage compressor operation. Refer to thermostat instructions.
8. Configure thermostat for two-stage compressor operation. Refer to thermostat instructions.
9. Configure thermostat for Dual Fuel Operation. Refer to thermostat instructions.
10. NO connection should be made to the furnace HUM terminal when using a thermostat with a 24 volt humidifier output.
11. Optional connection - If wire is connected to W2 on furnace control board, either dip switch SW1-2 or SW4-2 on furnace control
should be set in ON position to allow thermostat to control furnace at 2 stages Min/Max or Intermediate/Max.
12. Optional connection - If wire is connected, ACRDJ jumper on furnace control should be removed to allow thermostat to control
outdoor unit staging.
13. Furnace must control its own staging operation via furnace control algorithm. This is factory default.
14. The RVS Sensing terminal “L” should not be connected. This is internally used to sense defrost operation.
15. If thermostat has internal control of heat pump balance point, DO NOT SELECT the “FURNACE INTERFACE” or “BALANCE
POINT” option on the two-speed heat pump control board. Refer to thermostat instructions
16. Configure Dehumidify function to remove 24 VAC from Dehum terminal on a demand to dehumidify.
39
59MN7A
NOTES FOR THERMOSTAT WIRING DIAGRAMS
VENTING
Furnace is set in place in the required orientation.
59MN7A
Special Venting Requirements for Installations in
Canada
Les autorité es ayant juridiction (inspecteurs de gas, inspecteurs en
bâtiments, département des incendies, etc) devraient être consultées
avant l’installation afin de déterminer si un permis est requis.
!
Installation in Canada must conform to the requirements of
CAN/CSA B149 code. Vent systems must be composed of pipe,
fittings, cements, and primers listed to ULC S636. The special
vent fittings and accessory concentric vent termination kits and
accessory external drain trap have been certified to ULC S636 for
use with those Royal Pipe and IPEX PVC vent components which
have been certified to this standard. In Canada, the primer and
cement must be of the same manufacturer as the vent system –
GVS-65 Primer (Purple) for Royal Pipe or IPEX System 636,
PVC/CPVC Primer, Purple Violet for Flue Gas Venting and
GVS-65 PVC Solvent Cement for Royal Pipe or IPEX System
636(1)t, PVC Cement for Flue Gas Venting, rated Class IIA, 65 deg
C. must be used with this venting system - do not mix primers and
cements from one manufacturer with a vent system from a different
manufacturer. Follow the manufacturer’s instructions in the use of
primer and cement and never use primer or cement beyond its
expiration date.
The safe operation, as defined by ULC S636, of the vent system is
based on following these installation instructions, the vent system
manufacturer’s installation instructions, and proper use of primer
and cement. All fire stop and roof flashing used with this system
must be UL listed material. Acceptability under Canadian standard
CAN/CSA B149 is dependent upon full compliance with all
installation instructions. Under this standard, it is recommended
that the vent system be checked once a year by qualified service
personnel.
The authority having jurisdiction (gas inspection authority,
municipal building department, fire department, etc) should be
consulted before installation to determine the need to obtain a
permit.
CARBON MONOXIDE POISONING HAZARD
Failure to follow the steps outlined below for each appliance
connected to the venting system being placed into operation
could result in carbon monoxide poisoning or death.
The following steps shall be followed for each appliance
connected to the venting system being placed into operation,
while all other appliances connected to the venting system are
not in operation:
1. Seal any unused openings in venting system.
2. Inspect the venting system for proper size and
horizontal pitch, as required in the National Fuel Gas
Code, NFPA 54/ANSI Z223.1--2009 and these
instructions. In Canada, refer to CAN/CSA-B149.1--2010. Determine that there is no blockage or
restriction, leakage, corrosion and other deficiencies,
which could cause an unsafe condition.
3. As far as practical, close all building doors and
windows and all doors between the space in which the
appliance(s) connected to the venting system are
located and other spaces of the building.
4. Close fireplace dampers.
5. Turn on clothes dryers and any appliance not
connected to the venting system. Turn on any exhaust
fans, such as range hoods and bathroom exhausts, so
they are operating at maximum speed. Do not operate
a summer exhaust fan.
6. Follow the lighting instructions. Place the appliance
being inspected into operation. Adjust the thermostat
so appliance is operating continuously.
7. Test for spillage from draft hood equipped appliances
at the draft hood relief opening after 5 minutes of
main burner operation. Use the flame of a match or
candle.
8. If improper venting is observed during any of the
above tests, the venting system must be corrected in
accordance with the National Fuel Gas Code, NFPA
54/ANSI Z223.1--2009. In Canada, refer to CAN/
CSA--B149.1--2010.
9. After it has been determined that each appliance
connected to the venting system properly vents when
tested as outlined above, return doors, windows,
exhaust fans, fireplace dampers and any other
gas--fired burning appliance to their previous
conditions of use.
*IPEX System 636™ is a trademark of IPEX Inc.
Consignes spéciales pour l’installation de
ventilation au Canada
L’installation faite au Canada doit se conformer aux exigences du
code CAN/CSA B149--2010. Ce systême de ventillation doit se
composer de tuyaux, raccords, ciments et apprêts conformes au
ULC S636. La tuyauterie de ventillation des gaz, ses accessoires,
le terminal concentrique mural ainsi que l’ensemble du drain de
condensat extérieur ont été certifiés ULCS 636 pour l’application
des composantes Royal Pipe, IPEX PVC qui sont certifiées à ce
standard. Au Canada, l’apprêt et le ciment doivent être du même
fabricant que le système d’évacuation. L’apprêt GVS-65 (Purple) et
le ciment-solvant GVS-65 doivent être utilisé avec les Royal Pipe.
Système IPEX 636, apprêt PVC/CPVC, Purple pour évacuation
des gaz de combustion et système IPEX 636(1)t, ciment PVC pour
évacuation des gaz de combustion, coté classe IIA, 65 deg C.
doivent être utilisés avec le système d’évacuation IPEX 636 – Ne
pas combiner l ’apprêt et le ciment d’un manufacturier avec un
système d’évacuation d’un manufacturier différent.
Bien suivre les indications du manufacturier lors de l’utilisation de
l’apprêt et du ciment et ne pas utiliser ceux-ci si la date d’expiration
est atteinte.
L’opération sécuritaire, tel que définit par ULC S636, du système
de ventilation est basé sur les instructions d’installation suivantes,
ainsi que l’usage approprié de l’apprêt et ciment. Tout arrêt feu et
solin de toit utilisés avec ce système doivent être des matériaux
listés UL. L’acceptation du standard Canadien CAN/CSA B149
est directement relié à l’installation conforme aux instructions cihaut mentionnées. Le standard Canadien recommande l’ inspection
par un personnel qualifié et ce, une fois par année.
WARNING
General
If this furnace replaces a furnace that was connected to a vent
system or chimney, the vent or vent connectors of other remaining
appliances may need to be re--sized. Vent systems or vent
connectors of other appliances must be sized to the minimum size
as determined using appropriate table found in the current edition
of National Fuel Gas Code NFPA 54/ANSI Z--223.1. In Canada,
refer to CAN/CSA--B149.1.
An abandoned masonry chimney may be used as a raceway for
properly insulated and supported combustion--air (when
applicable) and vent pipes. Each furnace must have its own set of
combustion--air and vent pipes and be terminated individually, as
shown in Fig. 46 for Direct Vent (2--Pipe) system or Fig. 47 for
ventilated combustion air option.
40
Materials
U.S.A.
Combustion air and vent pipe, fittings, primers, and solvents must
conform to American National Standards Institute (ANSI)
standards and American Society for Testing and Materials (ASTM)
standards. See Table 11 for approved materials for use in the
U.S.A.
Canada
Special Venting Requirements for Installations in Canada
Installation in Canada must conform to the requirements of
CAN/CSA B149 code. Vent systems must be composed of pipe,
fittings, cements, and primers listed to ULC S636.
Venting Systems
A factory accessory KGAVT vent termination kit must be used for
all direct vent terminations. Termination kits are available for 2--in.
or 3--in. pipe. See Table 10 for available options.
Table 10 – Vent Termination Kit for Direct Vent (2--pipe)
Systems
DIRECT VENT
(2--- PIPE)
TERMINATION KIT
2 ---in. (51 mm)
Concentric Vent Kit
3 ---in. (76 mm)
Concentric Vent Kit
2 ---in. (51 mm)
Termination Bracket
Kit
3 ---in. (76 mm)
Termination Bracket
Kit
Single Penetration of
Wall or Roof
Single Penetration of
wall or Roof
DIAM. OF COMBUSTION AIR AND VENT
PIPES --- IN. (mm)
1, 1 ---1/2, 2, or 2 ---1/2
(24, 36, 51, 64 mm)
2 ---1/2, 3 or 4
(64, 76, 102 mm)
2 ---Pipe Termination
System
1, 1 ---1/2 or 2
(25, 36, 51 mm)
2 ---Pipe Termination
System
2 ---1/2, 3 or 4
(64, 76, 102 mm)
TERMINATION
SYSTEM
Direct Vent / 2-Pipe System
In a direct-vent (2-pipe) system, all air for combustion is taken
directly from outdoor atmosphere, and all flue products are
discharged to outdoor atmosphere. Combustion-air and vent pipes
must terminate together in the same atmospheric pressure zone,
either through the roof or a sidewall (roof termination preferred). A
factory accessory vent termination kit MUST be used in a direct
vent (2-pipe) system. See Fig. 44 for required clearances.
Ventilated Combustion Air Systems
In a ventilated combustion air option, the vent terminates and
discharges the flue products directly to the outdoors similar to a
direct vent system. See Fig. 45 for required clearances.
All air for combustion is piped directly to the furnace from a space
that is well ventilated with outdoor air (such as an attic or crawl
space) and the space is well isolated from the living space or
garage. Combustion air requirements for this option are the same as
the requirements for providing outside air for combustion for a
single pipe vent system. Refer to the “Air For Combustion and
Ventilation Section.
Provisions for adequate combustion, ventilation, and dilution air
must be provided in accordance with:
U.S.A. Installations: Section 9.3 NFPA 54/ANSI Z223.1-2009,
Air for Combustion and Ventilation and applicable provisions of
the local building codes.
Canadian Installations: Part 8 of CAN/CSA-B149.1-10. Venting
Systems and Air Supply for Appliances and all authorities having
jurisdiction.
Locating the Vent Termination
General
NOTE: Termination Requirements for the Provinces of
Alberta and Saskatchewan are located at the end of this
section.
Combustion--air (direct vent/2--pipe system only) and vent pipe
must terminate outside structure, either through sidewall or roof.
For vent termination clearance, refer to Fig. 44 for Direct
Vent/2--Pipe system and Fig. 45 for Non--direct Vent/1--Pipe
system. For exterior termination arrangements, refer to Fig. 46 for
Direct Vent/2--Pipe system and Fig. 47 for Non-- Direct/1--Pipe
system.
Roof termination is preferred since it is less susceptible to damage
or contamination, and it has less visible vent vapors. Sidewall
terminations require sealing or shielding of building surfaces with a
corrosive resistance material due to corrosive combustion products
of vent system.
NOTE: (Direct Vent/2--Pipe system ONLY) A factory accessory
termination kit MUST be used. See Table 10 for available options.
When determining appropriate location for termination, consider
the following guidelines:
1. Comply with all clearance requirements stated in Fig. 44 or
Fig. 45 per application.
2. Termination or termination kit should be positioned where
vent vapors will not damage plants/shrubs or air conditioning equipment.
3. Termination or termination kit should be positioned so that
it will not be affected by wind eddy, such as inside building
corners, nor by recirculation of flue gases, airborne leaves,
or light snow.
4. Termination or termination kit should be positioned where it
will not be damaged by or subjected to foreign objects such
as stones, balls, etc.
5. Termination or termination kit should be positioned where
vent vapors are not objectionable.
Direct Vent / 2-Pipe System
Direct vent (2--pipe) vent and combustion air pipes must terminate
outside the structure. Follow all clearances as shown Fig. 44.
Allowable vent and combustion air terminations are shown in Fig.
46.
Ventilated Combustion Air
The vent pipe for a Ventilated Combustion Air System must
terminate outdoors. Follow all vent termination clearances shown
in Fig. 45. Allowable vent terminations are shown in Fig. 47. The
combustion air pipe terminates in a well--ventilated attic or crawl
space. Follow the clearances as shown in Fig. 49. When the
furnace is installed in a well ventilated attic or crawlspace, install
the combustion air pipe as shown in Fig. .43
The combustion air pipe cannot terminate in attics or crawl spaces
that use ventilation fans designed to operate in the heating season.
If ventilation fans are present in these areas, the combustion air
pipe must terminate outdoors as a Direct Vent System.
Termination Requirements for the Provinces of Alberta and
Saskatchewan
The Provinces of Alberta and Saskatchewan require a minimum
unobstructed distance of 4 ft. (1.2 M) from the foundation to the
property line of the adjacent lot for vent termination of any
appliance with an input over 35,000 btuh. If there is less than 4 ft.
41
59MN7A
A furnace shall not be connected to a chimney flue serving a
separate appliance designed to burn solid fuel.
Other gas appliances with their own venting system may also use
the abandoned chimney as a raceway providing it is permitted by
local code, the current edition of the National Fuel Gas Code and
the vent or liner manufacturer’s installation instructions. Care must
be taken to prevent the exhaust gases from one appliance from
contaminating the combustion air of other gas appliances.
Do not take combustion air from inside the chimney when using
ventilated combustion air or single pipe vent option.
These furnaces can be vented as either direct vent furnace or as
ventilated combustion air system. Each type of venting system is
described below. Common venting between furnaces or other
appliances prohibited.
59MN7A
(1.2 M) of unobstructed distance to the property line of the
adjacent lot, no type of vent termination is permitted for appliances
with inputs greater than 35,000 btuh.
There are no additional restrictions on unobstructed distances
greater than 8 ft. (2.4 M). All single, two-pipe and concentric vents
may be used, providing all other Code and manufacturer’s
requirements in these instructions are adhered to. Refer to the
appropriate Vent Termination section above for locating the vent
termination
If the unobstructed distance from the foundation to the property
line of the adjacent lot is no less than 4 ft. (1.2 M) and no greater
than 8 ft. (2.4 M), it will be necessary to re-direct the flue gas
plume. In this situation, a concentric vent kit cannot be used. A
2-pipe termination (or single pipe termination when permitted) that
re-directs the flue gas away by use of an elbow or tee, certified to
ULC S636 from the adjacent property line must be used. See Fig.
48.
The concentric vent kit currently cannot be modified to attach an
elbow to the vent portion of the rain cap. A tee attached to the rain
cap could potentially direct the flue gas plume toward the intake air
stream and contaminate the incoming combustion air for the
furnace.
Refer to Fig. 48 for terminations approved for use in Alberta and
Saskatchewan.
Size the Vent and Combustion Air Pipes
General
Furnace combustion air and vent pipe connections are sized for
2-in. (51 mm) pipe. Any pipe diameter change should be made
outside furnace casing in vertical pipe. Any change is diameter to
the pipe must be made as close to the furnace as reasonably
possible.
The Maximum Vent Length for the vent and combustion air pipe
(when used) is determined from the Maximum Equivalent Vent
Length in Table 13 or 15, minus the number of fittings multiplied
by the deduction for each type of fitting used from Table 14.
The measured length of pipe used in a single or 2--pipe termination
is included in the total vent length. Include a deduction for a Tee
when used for Alberta and Saskatchewan terminations. Concentric
vent terminations, pipe lengths or elbows do not require a
deduction from the Maximum Equivalent Vent Length.
1. Measure the individual distance from the furnace to the termination for each pipe.
2. Select a Maximum Equivalent Vent Length (MEVL) longer
than the measured distance of the individual vent and combustion air connections to the vent termination.
3. Count the number of elbows for each pipe.
4. For each pipe, multiply the number of elbows by the equivalent length for the type of elbow used. Record the equivalent length of all the elbows for each pipe.
5. If a Tee is used on the termination (Alberta and Saskatchewan, when required) record the equivalent length of the
Tee used.
6. Calculate each individual Maximum Vent Length by subtracting the equivalent lengths of the fittings of the individual vent and combustion air pipes from the Maximum Equivalent Vent Length shown in Table 13 and 15.
7. If the Maximum Vent Length calculated is longer than the
individual measured length of the vent pipe and combustion
air pipe, then the diameter of pipe selected may be used.
8. If the Maximum Vent Length calculated is shorter than the
individual measured length of either the vent pipe or the
combustion air pipe, recalculate the Maximum Vent Length
using the next larger diameter pipe.
NOTE: If the calculated Maximum Vent Lengths results in
different diameter pipes for the vent and combustion air, select the
larger diameter for both pipes.
NOTE: If the Maximum Vent Length for diameter of the pipe
selected is longer than the measured length and the equivalent
length of all the fitting and terminations, recalculate using the next
smaller diameter. If the recalculated Maximum Vent Length is
longer than the measured length of the vent pipe and combustion
air pipe, then that diameter of pipe selected may be used.
When installing vent systems pipe lengths of 10 ft. (3.0 M) or less,
use the smallest allowable pipe diameter. Do not use pipe size
greater than required or incomplete combustion, flame disturbance,
or flame sense lockout may occur.
For vent systems longer than 10 ft. (3.0 M), any larger diameter
show in Table 13 or 15 may be used.
Combustion Air and Vent Piping Insulation
Guidelines
NOTE: Use closed cell, neoprene insulation or equivalent.
The vent pipe may pass through unconditioned areas. The amount
of exposed pipe allowed is shown in Table 12.
1. Using winter design temperature (used in load calculations),
find appropriate temperature for your application and furnace model.
2. Determine the amount of total and exposed vent pipe.
3. Determine required insulation thickness for exposed pipe
length(s).
4. When combustion air inlet piping is installed above a suspended ceiling, the pipe MUST be insulated with moisture
resistant insulation such as Armaflex or other equivalent
type of insulation.
5. Insulate combustion air inlet piping when run in warm, humid spaces.
6. Install the insulation per the insulation manufacturer’s installation instructions.
NOTE: Pipe length (ft. / M) specified for maximum pipe lengths
located in unconditioned spaces cannot exceed total allowable pipe
length as calculated from Table 13 or 15.
Configure the Furnace
!
WARNING
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
injury or death.
To route the vent pipe and combustion air pipe through the
furnace, the manufacturer supplied kit must be used. Failure
to properly seal the blower compartment from the furnace
vestibule could result in the circulation of carbon monoxide
throughout the structure. The vent pipe and combustion air
pipe must be a continuous pipe while passing through the
blower compartment. Seals supplied in this kit must be
installed per the instructions provided. Follow all
procedures outlined in these instructions.
Install the Vent and Combustion Air Pipe
With the furnace installed in the required position, remove the
desired knockouts from the casing. It will be necessary to remove
one knockout for the vent pipe and the other knockout for the
combustion air connection. (See Fig. 11.)
Use a flat blade screwdriver and tap on the knockout on opposite
sides, where the knockout meets the casing. Fold the knockout
down with duct pliers and work the knockout back and forth until
42
Installing the Vent Pipe Adapter and Combustion Air
Pipe Adapter
!
WARNING
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
injury or death.
To route the vent pipe and combustion air pipe through the
furnace, the manufacturer supplied kit must be used. Failure
to properly seal the blower compartment from the furnace
vestibule could result in the circulation of carbon monoxide
throughout the structure. The vent pipe and combustion air
pipe must be a continuous pipe while passing through the
blower compartment. Seals supplied in this kit must be
installed per the instructions provided. Follow all
procedures outlined in these instructions.
NOTE: The rubber coupling that attaches to the vent pipe adapter
must be used. The adapter seals the vent pipe to the casing and
reduces the strain on the vent elbow attached to the inducer.
1. Apply the gaskets to the vent pipe and combustion air pipe
adapters. See Fig. 36.
NOTE: The vent pipe adapter and the combustion air pipe adapter
have the same ID however, the combustion air pipe adapter has a
pipe stop at the end.
2. Align the screw holes in the plastic vent pipe adapter with
the dimples in the casing.
3. Pilot drill the screw holes for the adapter in the casing and
attach the vent pipe adapter to the furnace with sheet metal
screws
4. Slide the end of the rubber vent coupling with notches in it
over the standoffs on the vent pipe adapter.
5. Insert a length of vent pipe through the coupling into the
outlet of the vent elbow.
6. Tighten the clamp around the outlet of the vent elbow.
Torque the clamp to 15 lb--in.
Install the remaining vent and combustion air pipes as shown
below. It is recommended that all pipes be cut, prepared, and
preassembled before permanently cementing any joint.
1. Working from furnace to outside, cut pipe to required
length(s).
2. Deburr inside and outside of pipe.
3. Chamfer outside edge of pipe for better distribution of
primer and cement.
4. Clean and dry all surfaces to be joined.
5. Check dry fit of pipe and mark insertion depth on pipe.
6. Insert the vent pipe into the vent elbow.
7. Torque clamp on vent elbow 15 lb--in.
8. Torque clamp on vent coupling 15 lb--in.
9. Insert the combustion air pipe into the adapter.
Optional Installation of the Vent Pipe
This option provides a disconnect point for the vent pipe. The vent
pipe must be cemented to the plastic vent pipe adapter to maintain
a sealed vestibule. See Fig. 42.
1. Insert a length of vent pipe through the casing into the
outlet of the vent elbow.
2. Slide the plastic vent pipe adapter over the length of the
vent pipe down to the furnace casing. Mark the pipe where
it is flush with the outlet of the adapter.
3. Remove the pipe from the furnace and the adapter and cut
off any excess pipe.
4. Clean and prime the end of the pipe that is flush with the
vent adapter with a primer that is appropriate for the type of
pipe being used.
5. Re--insert the pipe through the casing into the vent elbow.
6. Tighten the clamp around the outlet of the vent elbow.
Torque the clamp to 15 lb--in.
7. Apply cement to the end of the pipe and to the inside of the
plastic vent adapter.
8. Slide the adapter over the vent pipe and align the screw
holes in the adapter with the dimples in the furnace casing.
9. Pilot drill 1/8--in. screw holes for the adapter in the casing
and secure the adapter to the furnace with sheet metal
screws.
10. Loosen the clamps on the rubber vent coupling.
11. Slide the end of the coupling with notches in it over the
standoffs in the vent pipe adapter.
12. Tighten the clamp of the coupling over the vent pipe
adapter. Torque the lower clamp around the vent pipe
adapter to 15 lb--in.
13. Pilot drill a 1/8--in. hole in the combustion air pipe adapter.
43
59MN7A
10. Pilot drill a screw hole through the adapter into the combustion air pipe and secure the pipe to the adapter with sheet
metal screws.
11. Seal around the combustion air pipe with silicone or foil
tape.
12. After pipes have been cut and preassembled, apply generous
layer of cement primer to pipe fitting socket and end of pipe
to insertion mark. Quickly apply approved cement to end of
pipe and fitting socket (over primer). Apply cement in a
light, uniform coat on inside of socket to prevent buildup of
excess cement. Apply second coat.
13. While cement is still wet, twist pipe into socket with 1/4--in.
turn. Be sure pipe is fully inserted into fitting socket.
14. Wipe excess cement from joint. A continuous bead of cement will be visible around perimeter of a properly made
joint.
15. Handle pipe joints carefully until cement sets.
16. Horizontal portions of the venting system shall be supported to prevent sagging. Support combustion air piping and
vent piping a minimum of every 5 ft. (1.5M)[3 ft. (.91M)
for SDR--21 or --26 PVC] using perforated metal hanging
strap or commercially available hangars designed to support
plastic pipe.
17. Prevent condensate from accumulating in the pipes by sloping the combustion air piping and vent piping downward
towards furnace a minimum of 1/4-in. per linear ft. with no
sags between hangers.
18. Complete the vent and combustion air pipe installation by
connecting the concentric vent or by installing the required
termination elbows as shown in Fig. 46, 47 and 48.
For Ventilated Combustion Air Termination, See Fig. 49
19. Use appropriate methods to seal openings where combustion air pipe and vent pipe pass through roof or sidewall.
it is removed. Trim any excess metal from the knockout with tin
snips.
The vent elbow can be rotated to the required location on the
casing if necessary. See Fig. 37. To rotate the vent elbow:
1. Loosen the clamp on the inlet of the vent elbow attached to
the inducer.
2. Rotate the vent elbow to the required position. There are
rounded notches in the vent elbow to align it with the
inducer housing for each orientation.
3. Tighten the clamp around the vent elbow. Torque the clamp
to 15 lb--in. See Fig. 38--41.
14. Complete the vent and combustion air pipe as shown in
“Install the Vent and Combustion Air Pipe”
Installing the Vent Termination
59MN7A
Roof Terminations
A roof termination of any type will require a 4-in. (102 mm)
flashing for a 2 inch (51 mm) concentric vent or a 5--in. diameter
(127 mm) flashing for a 3-inch (76 mm) concentric vent kit. For
two-pipe or single pipe vent systems, a flashing for each pipe of the
required diameter will be necessary.
It is recommended that the flashing be installed by a roofer or
competent professional prior to installing the concentric vent. The
terminations can be installed on a flat or pitched roof.
Concentric Vent
Single or multiple concentric vent must be installed as shown in
Fig. 46. Maintain the required separation distance between vents
or pairs of vents as shown in Fig. 46 and all clearance shown in
Fig. 44.
Cut one 4--in. (102 mm) diameter hole for 2--in. (51 mm) kit, or
one 5--in. (127 mm) diameter hole for 3--in. (76 mm) kit in the
desired location.
Loosely assemble concentric vent/combustion air termination
components together using instructions in kit.
Slide assembled kit with rain shield REMOVED through hole in
wall or roof flashing.
NOTE: Do not allow insulation or other materials to accumulate
inside of pipe assembly when installing it through hole.
Disassemble loose pipe fittings. Clean and cement using same
procedures as used for system piping.
Two--Pipe and Single--Pipe Terminations
Single and two pipe vent must be installed as shown in Fig. 46 and
47. Maintain the required separation distance between vents or
pairs of vents as shown in Fig. 46 and 47. and all clearance shown
in Fig. 44 and 45.
Cut the required number of holes in the roof or sidewall for vent
and (when used) combustion air pipes. Sidewall holes for two-pipe
vent terminations should be side-by-side, allowing space between
the pipes for the elbows to fit on the pipes.
Holes in the roof for two pipe terminations should be spaced no
more than 18 in. (457 mm) apart.
Termination elbows will be installed after the vent and (if used)
combustion air pipe is installed.
Sidewall Terminations
Concentric Vent Termination
guidelines provided in section “Locating The Vent Termination” in
this instruction.
1. Cut one 4--in. diameter hole for 2--in. kit, or one 5--in. diameter hole for 3--in. kit.
2. Loosely assemble concentric vent/combustion air termination components together using instructions in kit.
3. Slide assembled kit with rain shield REMOVED through
hole.
NOTE: Do not allow insulation or other materials to accumulate
inside of pipe assembly when installing it through hole.
4. Locate assembly through sidewall with rain shield positioned no more than 1--in. (25 mm) from wall as shown in
Fig. 46.
5. Disassemble loose pipe fittings. Clean and cement using
same procedures as used for system piping.
Direct Vent (2-- pipe) Termination
Determine an appropriate location for termination kit using the
guidelines provided in section “Locating The Vent Termination” in
this instruction.
1. Cut 2 holes, 1 for each pipe, of appropriate size for pipe size
being used.
2. Loosely install elbow in bracket and place assembly on
combustion--air pipe.
3. Install bracket as shown in Fig. 46 and 48.
NOTE: For applications using vent pipe option indicated by
dashed lines in Fig. 46 and 47, rotate vent elbow 90_ from
position.
4. Disassemble loose pipe fittings. Clean and cement using
same procedures as used for system piping.
For ventilated Combustion Air Terminations, terminate as
shown in Fig. 47.
(Direct Vent / 2-Pipe System ONLY)
When 2 or more furnaces are vented near each other, 2 vent
terminations may be installed as shown in Fig. 46, but next vent
termination must be at least 36 in. (914 mm) away from first 2
terminations. It is important that vent terminations be made as
shown in Fig. 46 to avoid recirculation of flue gases.
Inducer Outlet Restrictor
The loose parts bag may contain an inducer outlet restrictor. The
outlet restrictor is NOT used on these furnaces. Discard restrictor.
Determine an appropriate location for termination kit using the
44
Table 11 – Approved Combustion-Air and Vent Pipe, Fitting and Cement Materials (U.S.A. Installations)
MATERIAL
PIPE
FITTINGS
ABS
PVC
For ABS
PVC
PVC
ABS
For PVC
ABS
PVC
CPVC
CPVC
CPVC
For CPVC
Pipe
Pipe
—
Pipe
—
—
—
Pipe
Pipe
—
Pipe
Pipe
—
—
—
—
—
Fittings
Fittings
—
Fittings
Fittings
Fittings
—
—
—
SOLVENT CEMENT
AND PRIMERS
—
—
Solvent Cement
—
—
—
Solvent Cement
—
—
—
—
—
Solvent Cement
F628
ABS
Pipe
—
—
F656
F891
For PVC
PVC
—
Pipe
—
—
Primer
—
45
DESCRIPTION
Schedule--- 40
Schedule--- 40
For ABS
SDR--- 21 & SDR--- 26
Schedule--- 40
Schedule--- 40
For PVC
DWV at Schedule--- 40 IPS sizes
DWV
Schedule--- 40
Schedule--- 40
SDR
For CPVC
Cellular Core DWV at Schedule--- 40
IPS sizes
For PVC
Cellular Core Schedule--- 40 & DWV
59MN7A
ASTM SPECIFICATION
(MARKED ON MATERIAL)
D1527
D1785
D2235
D2241
D2466
D2468
D2564
D2661
D2665
F438
F441
F442
F493
Table 12 – Maximum Allowable Exposed Vent Lengths Insulation Table -- Ft. / M
Maximum Length of Uninsulated and Insulated Vent Pipe-Ft (M)
Modulating
Furnace High
Heat Input
Winter Design
Temp ° F (° C)
20 (-10)
0 (-20)
60000
-20 (-30)
-40 (-40)
59MN7A
20 (-10)
0 (-20)
60600
-20 (-30)
-40 (-40)
20 (-10)
0 (-20)
80000
-20 (-30)
-40 (-40)
20 (-10)
0 (-20)
100000
-20 (-30)
-40 (-40)
20 (-10)
0 (-20)
120000
-20 (-30)
-40 (-40)
Pipe
Length in
Ft. & M
No Insulation
3/8-in. (9.5 mm)
1/2-in. (12.7 mm)
Pipe Diameter-inches (mm)
Pipe Diameter-inches (mm)
Pipe Diameter-inches (mm)
1.5
2.0
2.5
3.0
4.0
1.5
2.0
2.5
3.0
4.0
1.5
2.0
2.5
3.0
4.0
(38)
(51)
(64)
(76)
(102)
(38)
(51)
(64)
(76)
(102)
(38)
(51)
(64)
(76)
(102)
Ft.
34.0
29.0
28.0
23.0
N/A
55.0
88.0
79.0
69.0
N/A
55.0
104.0
93.0
81.0
N/A
M
10.4
8.8
8.5
7.0
N/A
16.8
26.8
24.1
21.0
N/A
16.8
31.7
28.3
24.7
N/A
Ft.
14.0
9.0
7.0
0.0
N/A
55.0
49.0
43.0
34.0
N/A
55.0
60.0
52.0
42.0
N/A
M
4.3
2.7
2.1
0.0
N/A
16.8
14.9
13.1
10.4
N/A
16.8
18.3
15.8
12.8
N/A
Ft.
5.0
0.0
0.0
0.0
N/A
41.0
32.0
26.0
18.0
N/A
50.0
40.0
33.0
24.0
N/A
M
1.5
0.0
0.0
0.0
N/A
12.5
9.8
7.9
5.5
N/A
15.2
12.2
10.1
7.3
N/A
Ft.
0.0
0.0
0.0
0.0
N/A
30.0
21.0
16.0
8.0
N/A
37.0
28.0
22.0
13.0
N/A
M
0.0
0.0
0.0
0.0
N/A
9.1
6.4
4.9
2.4
N/A
11.3
8.5
6.7
4.0
N/A
Ft.
34.0
29.0
28.0
23.0
N/A
55.0
88.0
79.0
69.0
N/A
55.0
104.0
93.0
81.0
N/A
M
10.4
8.8
8.5
7.0
N/A
16.8
26.8
24.1
21.0
N/A
16.8
31.7
28.3
24.7
N/A
Ft.
14.0
9.0
7.0
0.0
N/A
55.0
49.0
43.0
34.0
N/A
55.0
60.0
52.0
42.0
N/A
M
4.3
2.7
2.1
0.0
N/A
16.8
14.9
13.1
10.4
N/A
16.8
18.3
15.8
12.8
N/A
Ft.
5.0
0.0
0.0
0.0
N/A
41.0
32.0
26.0
18.0
N/A
50.0
40.0
33.0
24.0
N/A
M
1.5
0.0
0.0
0.0
N/A
12.5
9.8
7.9
5.5
N/A
15.2
12.2
10.1
7.3
N/A
Ft.
0.0
0.0
0.0
0.0
N/A
30.0
21.0
16.0
8.0
N/A
37.0
28.0
22.0
13.0
N/A
M
0.0
0.0
0.0
0.0
N/A
9.1
6.4
4.9
2.4
N/A
11.3
8.5
6.7
4.0
N/A
Ft.
35.0
39.0
39.0
33.0
25.0
35.0
118.0 107.0
92.0
76.0
35.0
130.0 125.0 109.0
90.0
M
10.7
11.9
11.9
10.1
7.6
10.7
36.0
32.6
28.0
23.2
10.7
39.6
38.1
33.2
27.4
Ft.
22.0
16.0
14.0
7.0
0.0
35.0
69.0
60.0
49.0
35.0
35.0
83.0
72.0
60.0
45.0
M
6.7
4.9
4.3
2.1
0.0
10.7
21.0
18.3
14.9
10.7
10.7
25.3
21.9
18.3
13.7
Ft.
11.0
5.0
2.0
0.0
0.0
35.0
46.0
39.0
29.0
16.0
35.0
57.0
48.0
37.0
23.0
M
3.4
1.5
0.6
0.0
0.0
10.7
14.0
11.9
8.8
4.9
10.7
17.4
14.6
11.3
7.0
Ft.
4.0
0.0
0.0
0.0
0.0
35.0
33.0
26.0
17.0
4.0
35.0
41.0
34.0
24.0
11.0
M
1.2
0.0
0.0
0.0
0.0
10.7
10.1
7.9
5.2
1.2
10.7
12.5
10.4
7.3
3.4
Ft.
N/A
47.0
47.0
41.0
32.0
N/A
50.0
110.0 112.0
93.0
N/A
50.0
110.0 132.0 110.0
M
N/A
14.3
14.3
12.5
9.8
N/A
15.2
33.5
34.1
28.3
N/A
15.2
33.5
40.2
33.5
Ft.
N/A
21.0
19.0
12.0
1.0
N/A
50.0
74.0
61.0
45.0
N/A
50.0
89.0
74.0
57.0
M
N/A
6.4
5.8
3.7
0.3
N/A
15.2
22.6
18.6
13.7
N/A
15.2
27.1
22.6
17.4
Ft.
N/A
8.0
6.0
0.0
0.0
N/A
50.0
49.0
38.0
23.0
N/A
50.0
60.0
48.0
32.0
M
N/A
2.4
1.8
0.0
0.0
N/A
15.2
14.9
11.6
7.0
N/A
15.2
18.3
14.6
9.8
Ft.
N/A
1.0
0.0
0.0
0.0
N/A
42.0
34.0
24.0
10.0
N/A
50.0
43.0
32.0
18.0
M
N/A
0.3
0.0
0.0
0.0
N/A
12.8
10.4
7.3
3.0
N/A
15.2
13.1
9.8
5.5
Ft.
N/A
N/A
15.0
49.0
40.0
N/A
N/A
15.0
100.0 111.0
N/A
N/A
15.0
100.0 131.0
M
N/A
N/A
4.6
14.9
12.2
N/A
N/A
4.6
30.5
33.8
N/A
N/A
4.6
30.5
39.9
Ft.
N/A
N/A
15.0
17.0
6.0
N/A
N/A
15.0
75.0
57.0
N/A
N/A
15.0
90.0
70.0
M
N/A
N/A
4.6
5.2
1.8
N/A
N/A
4.6
22.9
17.4
N/A
N/A
4.6
27.4
21.3
Ft.
N/A
N/A
10.0
2.0
0.0
N/A
N/A
15.0
48.0
32.0
N/A
N/A
15.0
59.0
42.0
M
N/A
N/A
3.0
0.6
0.0
N/A
N/A
4.6
14.6
9.8
N/A
N/A
4.6
18.0
12.8
Ft.
N/A
N/A
1.0
0.0
0.0
N/A
N/A
15.0
32.0
17.0
N/A
N/A
15.0
41.0
25.0
M
N/A
N/A
0.3
0.0
0.0
N/A
N/A
4.6
9.8
5.2
N/A
N/A
4.6
12.5
7.6
* Pipe length (ft) specified for maximum pipe lengths located in unconditioned spaces. Pipes located in unconditioned space cannot exceed total allowable pipe
length calculated from Table 13 or 15.
† Insulation thickness based on R value of 3.5 per in.
46
NOTE: Maximum Equivalent Vent Length (MEVL) includes standard and concentric vent termination and does NOT include elbows.
Use Table 14 - Deductions from Maximum Equivalent Vent Length to determine allowable vent length for each application.
Table 13 – Maximum Equivalent Vent Length -- Ft. (M)
0 to 4500 Ft. (0 to 1370 M) Altitude
0 to 2000
(0 to 610)
2001 to 3000
(610 to 914)
3001 to 4000
(914 to 1219)
4001 to 4500
(1219 to
1370)
DIRECT VENT (2-PIPE) AND VENTILATED COMBUSTION AIR ONLY
Unit Size
BTU/Hr
Vent Pipe Diameter (in.)
1-1/2
60,000
55
80,000
35
100,000
NA
120,000
NA
2
2-1/2
3
4
(16.8)
135
(41.1)
235
(71.6)
265
(80.8)
(10.7)
130
(39.6)
175
(53.3)
235
(71.6)
265
(80.8)
50
(15.2)
110
(33.5)
235
(71.6)
265
(80.8)
15
(4.6)
100
(30.5)
250
(76.2)
NA
NA
60,000
45
(13.7)
127
(38.7)
222
(67.7)
250
(76.2)
80,000
30
(9.1)
90
(27.4)
165
(50.3)
222
(67.7)
249
(75.9)
40
(12.2)
104
(31.7)
223
(68.0)
250
(76.2)
11
(3.4)
93
(28.3)
237
100,000
NA
120,000
NA
60,000
40
80,000
25
100,000
NA
120,000
NA
60,000
35
80,000
23
100,000
NA
120,000
NA
NA
NA
(72.2)
(12.2)
119
(36.3)
210
(64.0)
235
(71.6)
(7.6)
85
(25.9)
155
(47.2)
210
(64.0)
232
(70.7)
40
(12.2)
98
(29.9)
211
(64.3)
236
(71.9)
8
(2.4)
86
(26.2)
224
NA
NA
(68.3)
(10.7)
115
(35.1)
204
(62.2)
228
(69.5)
(7.0)
85
(25.9)
150
(45.7)
202
(61.6)
224
(68.3)
40
(12.2)
94
(28.7)
205
(62.5)
229
(69.8)
83
(25.3)
217
(66.1)
NA
NA
59MN7A
Altitude
FT (M)
NA
* See notes at end of venting tables.
*See Table 15 for altitudes over 4500 ft. (1370 M)
ELBOW CONFIGURATIONS
VENT TERMINAL CONFIGURATIONS
Concentric
Long
Medium
Mitered
Standard
A11580
Table 14 – Deductions from Maximum Equivalent Vent Length -- Ft. (M)
Pipe Diameter (in):
1-1/2
2
2-1/2
3
4
Mitered 90º Elbow
8
(2.4)
8
(2.4)
8
(2.4)
8
(2.4)
8
(2.4)
Medium Radius 90º Elbow
5
(1.5)
5
(1.5)
5
(1.5)
5
(1.5)
5
(1.5)
Long Radius 90º Elbow
3
(0.9)
3
(0.9)
3
(0.9)
3
(0.9)
3
(0.9)
Mitered 45º Elbow
4
(1.2)
4
(1.2)
4
(1.2)
4
(1.2)
4
(1.2)
Medium Radius 45º Elbow
2.5
(0.8)
2.5
(0.8)
2.5
(0.8)
2.5
(0.8)
2.5
(0.8)
Long Radius 45º Elbow
1.5
(0.5)
1.5
(0.5)
1.5
(0.5)
1.5
(0.5)
1.5
(0.5)
Tee
16
(4.9)
16
(4.9)
16
(4.9)
16
(4.9)
16
0
(0.0)
0
(0.0)
0
(0.0)
0
(0.0)
Concentric Vent Termination
Standard Vent Termination
NA
0
(0.0)
NA
0
(0.0)
(4.9)
NA
0
(0.0)
Venting System Length Calculations
The maximum length for each vent pipe (inlet or exhaust) equals the Maximum Equivalent Vent Length (MEVL) from Table 13 or Table 15
minus the number of elbows multiplied by the deduction for each elbow in Table 14.
Standard vent terminations and concentric vent terminations count for zero deductions.
See Vent Manufacturers’ data for equivalent lengths of flexible vent piping.
DO NOT ASSUME that one foot of flexible vent pipe is equivalent to one foot of standard PVC vent pipe.
47
Example
A direct--vent 60,000 Btuh furnace installed at 2100 ft. (640 m) with 2--in.(51 mm) Vent piping. Venting system includes, FOR EACH
PIPE, (3) 90_ long radius elbows, (2) 45_ long radius elbows and a concentric vent kit.
Maximum Equivalent Vent Length
Deduct (3) 90 long radius
Deduct (2) 45 long radius
No deduction for Concentric Vent Kit
Maximum Vent Length
3
2
x
x
=
=
=
=
=
3 ft.
1.5 ft.
0 ft.
127 ft.
- 9 ft.
- 3 ft.
- 0 ft.
115 ft.
(From Table 13)
(From Table 14)
(From Table 14)
(From Table 14)
For EACH vent or inlet pipe
NOTE: Maximum Equivalent Vent Length (MEVL) includes standard and concentric vent termination and does NOT include elbows.
Use Table 14 - Deductions from Maximum Equivalent Vent Length to determine allowable vent length for each application.
Table 15 – Maximum Equivalent Vent Length -- Ft. (M)
4501 to 10,000 Ft. (0 to 1370 M) Altitude
59MN7A
Altitude
FT (M)
4501 to 5000
(1370 to
1524)
5001 to 6000
(1524 to
1829)
6001 to 7000
(1829 to
2134)
7001 to 8000
(2134 to
2438)
8001 to 9000
(2438 to
2743)
9001 to
10,000
(2743 to
3048)
DIRECT VENT (2-PIPE) AND VENTILATED COMBUSTION AIR ONLY
Vent Pipe Diameter
Unit Size
1-1/2
2
2-1/2
3
4
60,000
35
(10.7)
111
(33.8)
198
(60.4)
221
(67.4)
80,000
23
(7.0)
85
(25.9)
146
(44.5)
195
(59.4)
216
(65.8)
(12.2)
91
(27.7)
200
(61.0)
222
(67.7)
80
(24.4)
211
100,000
NA
120,000
NA
60,000
37
80,000
22
100,000
NA
120,000
NA
40
NA
NA
NA
(64.3)
(11.3)
103
(31.4)
186
(56.7)
207
(63.1)
(6.7)
76
(23.2)
137
(41.8)
183
(55.8)
200
(61.0)
33
(10.1)
85
(25.9)
188
(57.3)
208
(63.4)
74
(22.6)
199
(60.7)
NA
NA
NA
60,000
35
(10.7)
96
(29.3)
174
(53.0)
194
(59.1)
80,000
20
(6.1)
71
(21.6)
120
(36.6)
171
(52.1)
185
(56.4)
31
(9.4)
79
(24.1)
178
(54.3)
195
(59.4)
68
(20.7)
187
100,000
NA
120,000
NA
60,000
32
80,000
18
100,000
NA
120,000
NA
60,000
30
80,000
17
100,000
NA
89
(27.1)
163
(49.7)
181
(55.2)
(5.5)
66
(20.1)
120
(36.6)
159
(48.5)
170
(51.8)
29
(8.8)
73
(22.3)
167
(50.9)
182
(55.5)
62
(18.9)
175
NA
27
80,000
15
100,000
NA
120,000
NA
NA
NA
(53.3)
(9.1)
82
(25.0)
152
(46.3)
168
(51.2)
(5.2)
62
(18.9)
111
(33.8)
148
(45.1)
156
(47.5)
27
(8.2)
67
(20.4)
157
(47.9)
170
(51.8)
164
NA
60,000
(57.0)
(9.8)
NA
120,000
NA
NA
NA
NA
NA
56
(17.1)
(8.2)
76
(23.2)
142
(43.3)
156
(47.5)
(4.6)
57
(17.4)
103
(31.4)
137
(41.8)
142
(43.3)
24
(7.3)
62
(18.9)
147
(44.8)
157
(47.9)
51
(15.5)
153
(46.6)
NA
NA
(50.0)
NA
Notes:
1.
2.
3.
4.
5.
6.
7.
8.
Use only the vent pipe sizes shown for each furnace. It is NOT necessary to choose the smallest diameter pipe possible for venting.
NA --- Not allowed. Pressure switch will not close, or flame disturbance may result.
Vent sizing for Canadian installations over 4500 ft. (1370 M) above sea level are subject to acceptance by the local authorities having jurisdiction.
Size both the combustion air and vent pipe independently, then use the larger size for both pipes.
Assume the two 45_ elbows equal one 90_ elbow. Wide radius elbows are desirable and may be required in some cases.
Elbow and pipe sections within the furnace casing and at the vent termination should not be included in vent length or elbow count.
The minimum pipe length is 5 ft. (1.5 M) linear feet (meters) for all applications.
Use 3 ---in. (76 mm) diameter vent termination kit for installations requiring 4 ---in. (102 mm) diameter pipe.
48
Attach gaskets to vent pipe and
combustion air adapters.
A11314
Fig. 36 -- Vent Coupling and Adapter with Gaskets
VENT ELBOW CLAMP
TORQUE 15 LB-IN.
INDUCER OUTLET
VENT PIPE CLAMP
TORQUE 15 LB-IN.
MODULATING INDUCER ASSEMBLY
VENT ELBOW
A11286
Fig. 37 -- Inducer Vent Elbow
(Appearance May Vary)
49
59MN7A
Vent Coupling and Adapter
7
6
4 5
1
Any other unused
knockout may be used
for combustion air
connection.
Rotate vent elbow to
required position.
3
2 & 5
Rotate vent elbow to
required position.
A11309
6
7
6
Any other unused
knockout may be used
for combustion air
connection.
1
2 5
3
4 5
A11308
3
7
59MN7A
2 5
1
Any other unused
knockout may be used
for combustion air
connection.
4
5
A11310
1 Attach vent pipe adapter with gasket to furnace casing.
2 Align notches in rubber coupling over standoffs on adapter. Slide clamps over the coupling.
3 Slide vent pipe through adapter and coupling into vent elbow.
4 Insert vent pipe into vent elbow.
5 Torque all clamps 15 lb.-in.
6 Attach combustion air pipe adapter with gasket to furnace.
7 Attach combustion air pipe to adapter with silicone. Pilot drill a 1/8-in.
hole in adapter and secure with a #7 x 1/2-in sheet metal screw.
A11399
Fig. 38 -- Upflow Configurations
(Appearance May Vary)
50
3
Rotate vent elbow to
required position.
2 5
4
1
Rotate vent elbow to
required position.
5
4 5
1
2 5
3
Any other unused
knockout may be used
for combustion air
connection.
6
6
A11311
7
A11312
59MN7A
7
A11313
Downflow Vertical
Requires Accessory Internal Vent Kit.
See Product Data for current kit number.
1 Attach vent pipe adapter with gasket to furnace casing.
2 Align notches in rubber coupling over standoffs on adapter. Slide clamps over the coupling.
3 Slide vent pipe through adapter and coupling into vent elbow.
4 Insert vent pipe into vent elbow.
5 Torque all clamps 15 lb.-in.
6 Attach combustion air pipe adapter with gasket to furnace.
7 Attach combustion air pipe to adapter with silicone. Pilot drill a 1/8-in.
hole in adapter and secure with a #7 x 1/2-in sheet metal screw.
A11400
Fig. 39 -- Downflow Configurations
(Appearance May Vary)
51
59MN7A
HORIZONTAL LEFT VERTICAL VENT CONFIGURATION
HORIZONTAL LEFT LEFT VENT CONFIGURATION
HORIZONTAL LEFT RIGHT VENT CONFIGURATION*
*Requires Accessory Internal Vent Kit
See Product Data for Current Kit Number
1 Attach vent pipe adapter with gasket to furnace casing.
2 Align notches in rubber coupling over standoffs on adapter. Slide clamps over the coupling.
3 Slide vent pipe through adapter and coupling into vent elbow.
4 Insert vent pipe into vent elbow.
5 Torque all clamps 15 lb.-in.
6 Attach combustion air pipe adapter with gasket to furnace.
7 Attach combustion air pipe to adapter with silicone. Pilot drill a 1/8-in.
hole in adapter and secure with a #7 x 1/2-in sheet metal screw.
A11340
Fig. 40 -- Horizontal Left
(Appearance May Vary)
52
59MN7A
HORIZONTAL RIGHT VERTICAL VENT CONFIGURATION
HORIZONTAL RIGHT LEFT VENT CONFIGURATION*
*Requires Internal Vent Kit
See Product Data for Current Kit Number
HORIZONTAL RIGHT RIGHT VENT CONFIGURATION
1 Attach vent pipe adapter with gasket to furnace casing.
2 Align notches in rubber coupling over standoffs on adapter. Slide clamps over the coupling.
3 Slide vent pipe through adapter and coupling into vent elbow.
4 Insert vent pipe into vent elbow.
5 Torque all clamps 15 lb.-in.
6 Attach combustion air pipe adapter with gasket to furnace.
7 Attach combustion air pipe to adapter with silicone. Pilot drill a 1/8-in.
hole in adapter and secure with a #7 x 1/2-in sheet metal screw.
A11341
Fig. 41 -- Horizontal Right
(Appearance May Vary)
53
ALIGN NOTCHES IN VENT PIPE
COUPLING OVER STAND-OFF
ON ADAPTER. TORQUE LOWER
CLAMP 15 LB-IN. WHEN REMAINING
VENT PIPE IS INSTALLED, TORQUE
UPPER CLAMP TO 15 LB-IN.
59MN7A
VENT PIPE ADAPTER WITH GASKET
INSTALLED ON FURNACE VENT
PIPE IS CUT FLUSH WITH TOP OF
ADAPTER.
VENT PIPE FLUSH WITH ADAPTER
VENT PIPE FLUSH SHOWING COUPLING
A11339
Fig. 42 -- Vent Pipe Flush with Adaptor
Point elbow down towards
back of furnace
12” MINIMUM
256.0 mm
CASING SIDE ATTACHMENT
COMBUSTION AIR PIPE
(ATTIC OR CRAWLSPACE ONLY)
TOP PLATE ATTACHMENT
COMBUSTION AIR PIPE
(ATTIC OR CRAWLSPACE ONLY)
A11376
Fig. 43 -- Combustion Air Pipe Attachment
54
V
59MN7A
V
Item
A
Clearance Description
Clearance above grade, veranda, porch, deck, balcony or anticipated snow level
B
Clearance to a window or door that may be opened
C
Clearance to a permanently closed window
Vertical clearance to a ventilated soffit located above
the terminal within a horizontal distance of 2 feet (61
cm) from the centerline of the terminal
D
E
F
G
H
Clearance to an unventilated soffit
Clearance to an outside corner
Clearance to an inside corner
Clearance to each side of the centerline extended
above electrical meter or gas service regulator assembly
Canadian Installation (1)
U.S. Installation (2)
12 in. (305 mm). 18 in. (457 mm) above roof surface.
12 in. (305 mm)
12 in. (305 mm) for appliances > 10,000 Btuh (3kW)
and </--- 100,000 Btuh (30 kW), 36 in. (914 mm) for
appliances > 100,000 Btuh (30 kW)
9 in. (229 mm) for appliances > 10,000 Btuh (3kW)
and </--- 50,000 Btuh (15 kW), 12 in. (305 mm) for
appliances > 500,000 Btuh (15 kW)
For clearances not specified in ANSI Z223.1/NFPA 54 or
C A N / CSA B149.1, clearances shall be in accordance
with local installation codes and the requirements of
the gas supplier and the manufacturer’s installation
instructions.
For clearances not specified in ANSI Z223.1/NFPA 54 or
C A N / CSA B149.1, clearances shall be in accordance
with local installation codes and the requirements of
the gas supplier and the manufacturer’s installation
instructions.
3 ft. (.9 M) within 15 ft. (4.6 M) above the meter/
regulator assembly
3 ft. (.9 M) within 15 ft. (4.6 M) above the meter/
regulator assembly
I
Clearance to service regulator vent outlet
3 ft. (.9 M)
*3 ft. (.9 M) *For clearances not specified in ANSI Z223.1
/NFPA 54or C A N / CSA B149.1, clearances shall be in
accordance with local installation codes and the
requirements of the gas supplier and the manufacturer’s
installation instructions.
J
Clearance to non--- mechanical air supply inlet to
building or the combustion air inlet to any other appliance
12 in. (305 mm) for appliances > 10,000 Btuh(3kW)
and </--- 100,000 Btuh (30 kW), 36 in. (914 mm) for
appliances > 100,000 Btuh (30 kW)
9 in. (229 mm) for appliances > 10,000 Btuh (3kW)
and </--- 50,000 Btuh (15 kW), 12 in. (305 mm) for
appliances > 500,000 Btuh (15 kW)
K
Clearance to a mechanical air supply inlet
6 ft. (1.8 M)
L
Clearance under a veranda, porch, deck, or balcony
12 in. (305 mm). Permitted only if veranda, porch,
deck, or balcony is fully open on a minimum of two
sides beneath the floor.
3 ft. (.9 M)
For clearances not specified in ANSI Z223.1/NFPA 54 or
C A N / CSA B149.1, clearances shall be in accordance
with local installation codes and the requirements of
the gas supplier and the manufacturer’s installation
instructions.
M
Clearance to each side of the centerline extended
above or below vent terminal of the furnace to a dryer
or water heater vent, or other appliance’s direct vent
intake or exhaust
12 in. (305 mm)
12 in. (305 mm)
N
Clearance to the vent terminal of a dryer vent, water
heater vent, or other appliances direct vent intake or
exhaust
3 ft. (.9 M)
3 ft. (.9 M)
O
Clearance from a plumbing vent stack
3 ft. (.9 M)
P
Clearance above paved sidewalk or paved driveway
located on public property
7 ft. (2.1 M). A vent shall not terminate above a sidewalk or paved driveway that is located between two
single family dwellings and serves both dwellings.
3 ft. (.9 M)
For clearances not specified in ANSI Z223.1/NFPA 54 or
CAN/CSA B149.1, clearances shall be in accordance
with local installation codes and the requirements of
the gas supplier and the manufacturer’s installation
instructions.
(1) In accordance with the current C A N / CSA B 149.1, Natural Gas and Propane Installation Code.
(2) In accordance with the current ANSI Z223.1.NFPA 54, National Fuel Gas Code
Notes:
1. The vent for this appliance shall not terminate:
a. Over public walkways; or
b. Near soffit vents of crawl space vents or other areas where condensate or vapor could create a nuisance or hazard or property damage; or
c. Where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valves, or other equipment.
2. When locating vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the combustion products of adjacent vents.
Recirculation can cause poor combustion, inlet condensate problems, and accelerated corrosion of the heat exchangers.
3. Avoid venting under a deck or large overhang. Recirculation could occur and cause performance or system problems.
A11046
Fig. 44 -- Direct Vent Termination Clearance
55
59MN7A
Item
A
Clearance Description
Clearance above grade, veranda, porch, deck, balcony or anticipated snow level
B
Clearance to a window or door that may be opened
C
Clearance to a permanently closed window
Vertical clearance to a ventilated soffit located above
the terminal within a horizontal distance of 2 feet (61
cm) from the centerline of the terminal
D
E
F
G
H
Clearance to an unventilated soffit
Clearance to an outside corner
Clearance to an inside corner
Clearance to each side of the centerline extended
above electrical meter or gas service regulator assembly
Canadian Installation (1)
U.S. Installation (2)
12 in. (305 mm). 18 in. (457 mm) above roof surface.
12 in. (305 mm)
6 in. (152 mm) for appliances </--- 10,000 Btuh (3kW)
12 in. (305 mm) for appliances > 10,000 Btuh (3kW),
and </--- 100,000 Btuh (30kW), 36 in. (914 mm) for
appliances > 100,000 Btuh (30 kW)
4 ft. (1.2 M) below or to the side of the opening. 1 ft.
(.3 M) above the opening.
For clearances not specified in ANSI Z223.1/NFPA 54 or
CAN/CSA B149.1, clearances shall be in accordance
with local installation codes and the requirements of
the gas supplier and the manufacturer’s installation
instructions.
For clearances not specified in ANSI Z223.1/NFPA 54 or
CAN/CSA B149.1, clearances shall be in accordance
with local installation codes and the requirements of
the gas supplier and the manufacturer’s installation
instructions.
3 ft. (.9 M) within 15 ft. (4.6 M) above the meter/
regulator assembly
3 ft. (.9 M) within 15 ft. (4.6 M) above the meter/regulator assembly.
* 3 ft. (.9 M) * For clearances not specified in ANSI
Z223.1/NFPA 54 or C A N / CSA B149.1, clearances shall
be in accordance with local installation codes and the
requirements of the gas supplier and the manufacturer’s
installation instructions.
I
Clearance to service regulator vent outlet
3 ft. (.9 M)
J
Clearance to non--- mechanical air supply inlet to
building or the combustion air inlet to any other appliance
6 in. (152 mm) for appliances </--- 10,000 Btuh (3kW)
12 in. (305 mm) for appliances > 10,000 Btuh (3kW),
and </--- 100,000 Btuh (30kW), 36 in. (914 mm) for
appliances > 100,000 Btuh (30 kW)
K
Clearance to a mechanical air supply inlet
6 ft. (1.8 M)
L
Clearance under a veranda, porch, deck, or balcony
12 in. (305 mm). Permitted only if veranda, porch,
deck, or balcony is fully open on a minimum of two
sides beneath the floor.
M
Clearance to each side of the centerline extended
above or below vent terminal of the furnace to a dryer
or water heater vent, or other appliance’s direct vent
intake or exhaust
12 in. (305 mm)
12 in. (305 mm)
N
Clearance to the vent terminal of a dryer vent, water
heater vent, or other appliances direct vent intake or
exhaust
3 ft. (.9 M)
3 ft. (.9 M)
O
Clearance from a plumbing vent stack
3 ft. (.9 M)
P
Clearance above paved sidewalk or paved driveway
located on public property
3 ft. (.9 M)
7 ft. (2.1 M). A vent shall not terminate above a sidewalk or paved driveway that is located between two
single family dwellings and serves both dwellings.
4 ft. (1.2 M) below or to the side of the opening. 1 ft.
(.3 M) above the opening.
3 ft. (.9 M)
For clearances not specified in ANSI Z223.1/NFPA 54 or
C A N / CSA B149.1, clearances shall be in accordance
with local installation codes and the requirements of
the gas supplier and the manufacturer’s installation
instructions.
7 ft. (2.1 M).
(1) In accordance with the current C A N / CSA B 149.1, Natural Gas and Propane Installation Code.
(2) In accordance with the current ANSI Z223.1.NFPA 54, National Fuel Gas Code
Notes:
1. The vent for this appliance shall not terminate:
a. Over public walkways; or
b. Near soffit vents of crawl space vents or other areas where condensate or vapor could create a nuisance or hazard or property damage; or
c. Where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valves, or other equipment.
2. When locating vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the combustion products of adjacent vents.
Recirculation can cause poor combustion, inlet condensate problems, and accelerated corrosion of the heat exchangers.
3. Avoid venting under a deck or large overhang. Recirculation could occur and cause performance or system problems.
A11047
Fig. 45 -- Ventilated Combustion Air and Non--Direct Vent Termination Clearance
56
Roof Te rmination (Preferred)
At least 36 in.
(914mm)
Concentric Vent and Combustion Air
Roof Termination (preferred)
A
Ve r tical separation
between combustion
air and vent
8 3/4 in. (222mm)f or 3 in. (76mm)ki t
6 3/4 in. (172mm)for 2 in. (51mm) ki t 18 in. maximum (457mm)
A
At least
36 in.
(914mm)
Maintain 12 in. (305mm)min.
clearance above
highest anticipated
snow level
Maximum of 24 in.(614mm)
above roof
Maintain 12 in. (305mm)
min. clearance above
highest anticipated
snow level, maximum of
24 in. above roof
1 in. (25mm) maximum (typ) from wall to inlet
Abandoned masonr y
used as raceway
(per code)
12 in. (305mm) minimum from
overhang or roof
Note: "A" denotes 0 to < 2 in. (51mm)
Between the first 2 vents
Third vent must be > 36 in. away
(914mm)
At
le
36 ast
in
.
12 in. min from
overhang or roof
(typ)
A
Maintain 12 in. (305mm)
min. clearance above
highest anticipated
snow level or grade
whichever is greater
59MN7A
Concentric Vent
and Combustion - Air
Side Te rmination
A
At least 36 in.
(914mm)
12 in. (305mm)
separation between
bottom ofcomb ustion air and
bottom of vent (typ)
90°
A
Side wall termination
of less than 12 in. (305mm) above highest snow level
Maintain 12 in. (305mm)
min. clearance above
highest anticipated
snow level or grade
whichever is greater (typ)
6 in.
ast 3
At le mm)
(914
A05090
Fig. 46 -- Combustion Air and Vent Pipe Termination for Direct Vent (2--Pipe) System
Roof Termination (Preferred)
Vent
Maintain 12 in (305mm)
.
minimum clearance
above highest anticipated
snow level maximum of
24 in. (610mm) above. roof
Abandoned masonry
used as raceway
(per code)
12 in. min. (305 mm)from
overhang or roof
6 in. (152mm) minimum clearance
between wall and end of vent pipe.
10 in. (254mm) maximum pipe length
12 in. (305 mm) min. from
overhang or roof
Maintain 12 in. (305mm)
minimum clearance
above highest anticipated
snow level or grade
whichever is greater
Sidewall Termination
with Straight Pipe (preferred)
90°
Maintain 12 in. (305mm)
minimum clearance
above highest anticipated
snow level or grade
whichever is greater.
Side wall termination
with 2 elbows (preferred)
A05091
Fig. 47 -- Vent Pipe Termination for Non--Direct Vent and Ventilated Combustion Air System
57
NOTE: This illustration is for
reference only. Your unit may
differ in appearance or may not
include all components shown.
OVERHANG OR ROOF
VENT
Angle
22.5 o
to
45 o
off wall BRACKET
59MN7A
COUPLING
12 IN. SEPARATION
BETWEEN BOTTOM OF
COMBUSTION AIR AND
BOTTOM OF VENT
COMBUSTION-AIR
(ELBOW PARALLEL
TO WALL)
MAINTAIN 12 IN.
CLEARANCE
ABOVE HIGHEST
ANTICIPATED SNOW
LEVEL OR GRADE,
WHICHEVER IS
GREATER.
L10F022
EXHAUST
OVERHANG
Clearance to overhang per code
12 in. (304.8mm) MIN. Ground
Level OR Snow Level
A11346
Fig. 48 -- Alberta and Saskatchewan Vent Termination
58
Ventilated Combustion
Air intake pipe
Pipe hangar
59MN7A
3” (76 mm)
12” (305 mm)
Ventilated Combustion Air
intake termination in crawl
space
CRAWL SPACE
highest level of insulation
ATTIC
A10497
Fig. 49 -- Vent Terminations for Ventilated Combustion Air
59
START--UP, ADJUSTMENT, AND SAFETY
CHECK
General
59MN7A
1. Furnace must have a 115-v power supply properly connected and grounded.
NOTE: Proper polarity must be maintained for 115-v wiring.
Control status indicator light flashes rapidly and furnace does not
operate if polarity is incorrect.
2. Thermostat wire connections at terminals R, W/W1, G,
Y/Y2, etc. must be made at 24-v terminal block on furnace
control. See communicating wall control instructions for
proper wiring of communicating controls.
3. Natural gas service pressure must not exceed 0.5 psig (14in. w.c.), but must be no less than 0.16 psig (4.5-in. w.c.).
4. Blower door must be in place to complete 115-v electrical
circuit to furnace.
!
CAUTION
2. Locate A/C setup switches on furnace control.
3. Determine air conditioning tonnage used.
4. Configure the switches for the required cooling airflow.
NOTE: Excessive airflow caused by improper A/C switch setup
may cause condensate blow-off in cooling mode.
5. Replace blower door.
Continuous Fan (CF) Setup Switches (SW3)
The CF setup switches are used to select desired airflow when
thermostat is in continuous fan mode or to select low-cooling
airflow for two-speed cooling units. This setup feature allows
continuous fan airflow or low-cooling airflow to be adjusted. To
set desired continuous fan airflow or low-cooling airflow:
1. Remove blower door.
2. Locate CF setup switches on furnace control.
3. Determine desired continuous fan airflow or low-cooling
airflow.
4. Configure the switches for the required continuous fan or
low--cooling airflow.
5. Replace blower door.
UNIT OPERATION HAZARD
Additional Setup Switches (SW4)
Failure to follow this caution may result in intermittent unit
operation or performance satisfaction.
The furnace control has 3 additional setup switches labeled SW4.
Setup switch SW4-2 can be used to lock the furnace into
intermediate heat. When setup switch SW4-2 is ON it will over
ride setup switch SW1-2 if it is ON. SW4--3 is used to adjust
airflow. To activate setup switch SW4-2 and SW4--3:
1. Remove blower door.
2. Locate setup switch SW4 on furnace control.
3. Configure the switches for the required heat stages and
airflow if necessary.
4. Replace blower door.
These furnaces are equipped with a manual reset limit
switch in burner assembly. This switch opens and shuts off
power to the gas valve is an overheat condition (flame
rollout) occurs in burner assembly. Correct inadequate
combustion--air supply or improper venting condition
before resetting switch. DO NOT jumper this switch.
Before operating furnace, check flame rollout manual reset switch
for continuity. If necessary, press button to reset switch.
EAC-1 terminal is energized whenever blower operates. HUM
terminal is only energized when blower is energized in heating.
Prime Condensate Trap with Water
!
Select Setup Switch Positions
CAUTION
UNIT OPERATION HAZARD
There are 4 sets of setup switches on the furnace control board.
These switches configure the furnace for correct application
requirement. They also select the airflow settings for Air
Conditioning and Continuous Fan CFMs.
The Setup Switch locations are shown and described on Fig. 54.
The set up switches are also shown on the unit wiring label.
Failure to follow this caution may result in intermittent unit
operation or performance satisfaction.
Condensate trap must be PRIMED or proper draining may
not occur. The condensate trap has two internal chambers
which can ONLY be primed by pouring water into the
inducer drain side of condensate trap.
Setup Switches (SW1)
The furnace control has 8 setup switches that may be set to meet
the application requirements. To set these setup switches for the
appropriate requirement:
S Remove blower door.
S Locate setup switches on furnace control.
S Configure the set-up switches as necessary for the application.
S Replace blower door.
1. Remove upper and middle collector box drain plugs opposite of the condensate trap. (See Fig. 57.)
2. Connect field-supplied 1/2-in. (13 mm) OD tube to upper
collector box drain connection.
3. Insert field-supplied funnel into tube.
4. Pour one quart of water into funnel/tube. Water should run
through collector box, overfill condensate trap, and flow into open field drain.
5. Remove funnel; replace collector box drain plug.
6. Connect field-supplied 1/2-in. (13 mm) OD tube to middle
collector box drain port.
7. Pour one quart of water into funnel/tube. Water should run
through collector box, overfill condensate trap, and flow into open field drain.
8. Remove funnel and tube from collector box and replace collector box drain plug.
NOTE: If a bypass humidifier is used, setup switch SW1-3
(Min/Int Heat Rise Adjust) should be in ON position. This
compensates for the increased temperature in return air resulting
from bypass.
NOTE:
If modulating dampers are used, blower motor
automatically compensates for modulating dampers.
Air Conditioning (A/C) Setup Switches (SW2)
The air conditioning setup switches are used to match furnace
airflow to cooling unit used.
To set the desired cooling airflow:
1. Remove blower door.
60
If not previously done, purge the lines after all connections have
been made and check for leaks.
!
WARNING
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Never purge a gas line into a combustion chamber. Never
test for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection
of leaks to check all connections. A fire or explosion may
result causing property damage, personal injury or loss of
life.
Adjustments
!
CAUTION
FURNACE DAMAGE HAZARD
Failure to follow this caution may result in reduced furnace
life.
DO NOT redrill orifices. Improper drilling (burrs,
out--of--round holes, etc.) can cause excessive burner noise
and misdirection of burner flames. This can result in flame
impingement of heat exchangers, causing failures. (See Fig.
51.)
For proper operation and long term reliability, the Furnace input
rate must be within +/--2 percent of input rate on furnace rating
plate.
The gas input rate on rating plate is for installations at altitudes up
to 2000 ft. (609.6M).
In the USA., the input rating for altitudes above 2000 ft. (609.6M)
must be reduced by 2 percent for each 1000 ft. (304.8M) above sea
level. Refer to Table 16.
In Canada, the input rating must be derated by 5 percent for
altitudes of 2000 ft. (609.6M) to 4500 ft. (1371.6M) above sea
level.
To adjust manifold pressure to obtain the proper input rate, first,
determine if the furnace has the correct orifice installed. At higher
altitudes or different gas heat contents, it may be necessary to
change the factory orifice to a different orifice. Tables have been
provided in the furnace installation instructions to match the
required orifice to the manifold pressure to the heat content and
specific gravity of the gas. To do this:
a. Obtain average heat value (at installed altitude) from local
gas supplier.
b. Obtain average specific gravity from local gas supplier.
c. Find installation altitude range for your installation in the
manifold pressure tables. See Table 19 for 20,000 Btuh
Max--Heat/8,000 Btuh min--heat per burner or Table 20 for
20,200 Btuh Max--Heat/8,000 Btuh Min--Heat per burner.
d. Find closest natural gas heat value and specific gravity in
Table 19 or Table 20 depending on furnace gas input rate.
e. Follow heat value and specific gravity lines to point of
intersection to find orifice size and maximum and minimum
manifold pressure settings for proper operation.
f. Check and verify burner orifice size in furnace. Never
assume orifice size. Always check and verify.
NOTE: For Canadian altitudes of 2000 to 4500 ft. (609.6 to
1371.6M), use USA altitudes of 2001 to 3000 ft. (609.6 to
914.4M).
NOTE: If orifice hole appears damaged or it is suspected to have
been redrilled, check orifice hole with a numbered drill bit of
correct size. Never redrill an orifice. A burr--free and squarely
aligned orifice hole is essential for proper flame characteristics.
See Example 1.
g. Replace original orifice with correct size, if required by
Table 19 or Table 20 depending on furnace gas input rate.
Use only factory--supplied orifices. See EXAMPLE 1.
EXAMPLE 1
EXAMPLE: 0 -- 2000 ft. (0 -- 609.6M) altitude
Heating value = 1050 Btu/cu ft.
Specific gravity = 0.62
Therefore: Orifice No. 44
Manifold pressure: 3.4--in. w.c. for maximum heat, 0.55--in. w.c.
for minimum heat.
* Furnace is shipped with No. 44 orifices. In this example, all main
burner orifices are the correct size and do not need to be changed to
obtain proper input rate.
The inlet gas pressure must be checked with the furnace operating
in maximum heat. This is necessary to make sure the inlet gas
pressure does not fall below the minimum pressure of 4.5 in. w.c.
for natural gas. The maximum inlet gas pressure is 13.6 in. of water
column. If the inlet pressure is too low, you will not be able to
adjust the manifold pressure to obtain the proper input rate. To
check the inlet gas pressure:
1. Make sure the gas supply is turned off to the furnace and at
the electric switch on the gas valve.
2. Remove the 1/8 in. NPT plug from the inlet pressure tap on
the gas valve.
3. Connect a manometer to the inlet pressure tap on gas valve.
4. Turn on furnace power supply.
5. Turn gas supply manual shutoff valve to ON position.
6. Turn furnace gas valve switch to ON position.
7. Jumper the R to W/W1 and W2 thermostat connections at
the furnace control board.
8. When main burners ignite, confirm inlet gas pressure is
Between 4.5 in. w.c. and 13.6 in. w.c.
9. Remove jumper across thermostat connections to terminate
call for heat. Wait until the blower off delay is completed.
10. Turn furnace gas valve electric switch to OFF position.
11. Turn gas supply manual shutoff valve to OFF position.
12. Turn off furnace power supply.
13. Remove manometer from the inlet pressure tap of the gas
valve.
14. Apply pipe dope sparingly to end of inlet gas pipe plug and
re--install in the gas valve.
For proper operation and long term reliability, the manifold
pressure must be adjusted within +/--2 percent of input rate on
furnace rating plate.
The modulating furnace manifold pressure is set at two points. The
first point is Maximum Heat. The second point is Minimum Heat.
Do not adjust Intermediate Heat manifold pressure. Intermediate
Heat manifold pressure is checked as part of the temperature rise,
but is not adjustable. Always adjust Maximum Heat first, then
Minimum Heat.
NOTE: DO NOT set Maximum Heat manifold pressure less than
3.2--in. w.c. or more than 3.8 in. w.c. for natural gas.
To adjust manifold pressure to obtain input rate for Maximum
Heat:
61
59MN7A
Purge Gas Lines
59MN7A
1. Make sure the gas supply is turned off to the furnace and at
the electric switch on the gas valve.
2. Remove the 1/8 inch NPT plug from the outlet pressure tap
on the gas valve.
3. Connect a manometer to the outlet pressure tap on gas
valve.
4. Turn on furnace power supply.
5. Turn gas supply manual shutoff valve to ON position.
6. Turn furnace gas valve switch to ON position.
7. Jumper the R to W/W1 and W2 thermostat connections at
the furnace control board.
8. After the main burners ignite and the blower starts, confirm
Maximum Heat manifold pressure is correct, based on the
manifold pressure tables in the installation instructions.
9. To adjust the Maximum Heat manifold pressure, slowly turn
adjusting screw counterclockwise to decrease manifold
pressure or clockwise to increase manifold pressure. Turn
adjustment no more than one click per second until you
obtain the required manifold pressure.
10. Main burner flame should be clear blue, almost transparent.
11. After adjusting the Maximum Heat manifold pressure,
remove jumpers across thermostat connections to terminate
the call for heat.
12. Wait for blower off-delay to finish then reset 115-v power to
furnace.
To adjust manifold pressure to obtain input rate for Minimum Heat:
1. Turn SW1--2 ON and SW4--2 must be OFF.
2. Jumper R and W/W1 thermostat connections on control to
start furnace.
3. After the main burners ignite and the blower starts, confirm
Minimum Heat manifold pressure is correct, based on the
manifold pressure tables in the installation instructions.
4. To adjust the Minimum Heat manifold pressure, slowly turn
adjusting screw counterclockwise to decrease manifold
pressure or clockwise to increase manifold pressure. Turn
adjustment no more than one click per second until you
obtain the required manifold pressure.
5. After adjusting the manifold pressure, remove jumpers
across thermostat connections to terminate the call for heat.
Wait until the blower off delay is completed.
6. Move setup switch SW1-2 to the OFF position.
7. Turn gas supply manual shutoff valve to OFF position.
8. Turn off furnace power supply.
9. Remove manometer from the inlet pressure tap of the gas
valve.
10. Apply pipe dope sparingly to end of inlet gas pipe plug and
re-install in the gas valve.
11. Re-install cap over adjustment screw on the top of the gas
valve.
Adjust Temperature Rise
!
CAUTION
FURNACE DAMAGE HAZARD
Failure to follow this caution may result in:
S Overheating the heat exchangers or condensing flue gases
in heat exchanger areas not designed for condensate.
S Shortened furnace life
S Component damage.
Temperature rise must be within limits specified on furnace
rating plate. Recommended operation is at midpoint of rise
range or slightly above.
When setup switch SW1-4 is ON, operation will be near the high
end of the rise range for improved comfort.
Furnace must operate within ranges of temperature rise specified
on the furnace rating plate. Determine air temperature rise as
follows:
1. Place thermometers in return and supply ducts as near
furnace as possible. Be sure thermometers do not see heat
exchanger so that radiant heat does not affect readings. This
practice is particularly important with straight-run ducts.
2. When thermometer readings stabilize, subtract return-air
temperature from supply-air temperature to determine air
temperature rise.
NOTE: Temperature rise can be determined for Minimum Heat,
Intermediate Heat and Maximum Heat operation by locking the
furnace in each mode of operation. The mode of operation is based
on the position of Set-up switch SW1-2 and SW4-2 on the furnace
control board.
The furnace is capable of automatically providing proper airflow to
maintain the temperature rise within the range specified on furnace
rating plate. If temperature rise is outside this range, proceed as
follows:
a. Check gas input for minimum, intermediate and maximum
heat operation.
b. Check derate for altitude if applicable.
c. Check all return and supply ducts for excessive restrictions
causing static pressure greater than 0.5-in. w.c.
d. Ensure Min/Int Heat Rise Adjust switch SW1--3 on furnace
control is in ON position when a bypass humidifier is used.
(See Fig. 54 for switch location.)
e. Check Troubleshooting Guide for Variable--Speed Step
Modulating Condensing Furnaces.
To lock the furnace in Minimum Heat:
1. Turn SW1--2 ON at the furnace control. Set up switch
SW4--2 must be OFF.
2. Connect a jumper across R and W/W1 at the thermostat
terminals at the furnace control.
3. Allow the burners to ignite and the blower to turn on.
4. Allow the supply temperature to stabilize and verify the
proper rise range.
If the temperature rise is too high or too low in Minimum Heat:
1. Remove jumpers from R and W/W1.
2. Wait until the blower off delay is completed.
3. Turn 115 VAC power off.
4. Check the position of Set up switch SW1--3. When set to
ON, airflow is raised 18% for Minimum Heat and for
Intermediate Heat. Factory default position is OFF.
5. Turn 115 VAC power on.
62
!
WARNING
FIRE HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Reinstall manifold pressure tap plug in gas valve to prevent
gas leak.
!
Adjust Blower Off Delay (Heat Mode)
a. Remove blower door if installed.
b. Turn Dip switch SW--7 or SW--8 ON or OFF for desired
blower off delay. (See Table 17 and Fig. 34 , 54 and 63.)
Adjust Cooling Airflow – High-Speed and
Low-Speed Cooling
The ECM blower can be adjusted for a range of airflows for
low-speed or high-speed cooling. See Table 7 – Air Delivery –
CFM (With Filter ) and Fig. 54 – Furnace Setup Switches and
Descriptions. Depending on the model size, the cooling airflow
can be adjusted from 1.5 to 6 tons based on 350 CFM ton.
NOTE: 6 ton airflow will truncate at 2200 CFM on applicable
models.
The high-speed or single-speed cooling airflow is adjusted by
turning Setup switches SW2-1, SW2-2 and SW2-3 either ON or
OFF. Select the required airflow from Table 7. Table 7 is based
upon 350 CFM per ton. For other CFM per ton Setup switch
selections, see Fig. 34, Fig. 54 and Fig. 63.
The Continuous Fan airflow selection via Setup switches SW3 is
also the airflow for low-speed cooling when the furnace is used
with a 2-speed cooling or heat pump unit. Adjust the Continuous
Fan CFM Setup switches SW3 to match the airflow required for
low-speed cooling. Select the required airflow from Table 7 and
Fig. 54.
NOTE: The airflow selected via SW3 (Low-Speed Cooling
Airflow) cannot exceed the airflow selected via SW2 (High-Speed
Cooling Airflow). For other CFM per ton Setup switch selections,
see Fig. 34 and Fig. 54.
NOTE: The airflow settings for SW2 and SW3 selections are the
same, EXCEPT for the default values. See Table 7.
For a complete explanation of cooling airflow, refer to the section
titled “Sequence of Operation.”
Adjust Continuous Fan Airflow (and Low-Speed
Cooling Airflow)
NOTE: When the furnace is used with a 2-speed cooling or heat
pump unit, the airflow selected for continuous fan via Setup switch
SW3 will also be the airflow used for low-speed cooling, and vice
versa. The continuous fan speed can be further adjusted at a
conventional thermostat using the continuous fan speed select
function. Changing the continuous fan speed at a conventional
thermostat DOES NOT change the low-speed cooling airflow
selected via SW3 at the control board.
NOTE: When the furnace is used with a 2-speed cooling or heat
pump unit, adjust the Continuous Fan CFM Setup switches SW3
to match the airflow required for low-speed cooling.
Select the required continuous fan airflow using Setup switches
SW3 as shown in Fig. 54 and Table 7.
Adjust Thermostat Heat Anticipator.
a. Mechanical thermostat. Set thermostat heat anticipator to
match the amp. draw of the electrical components in the
R--W/W1 circuit. Accurate amp. draw readings can be obtained at the wires normally connected to thermostat subbase terminals, R and W. The thermostat anticipator should
NOT be in the circuit while measuring current.
(1.) Set SW1--2 switch on furnace control board to ON.
(2.) Remove thermostat from subbase or from wall.
(3.) Connect an amp. meter as shown in Fig. 52 across
the R and W subbase terminals or R and W wires
at wall.
(4.) Record amp. draw across terminals when furnace is
in minimum heat and after blower starts.
(5.) Set heat anticipator on thermostat per thermostat
instructions and install on subbase or wall.
CAUTION
FURNACE OVERHEATING HAZARD
Failure to follow this caution may result in reduced furnace
life.
Recheck temperature rise. It must be within limits specified
on the rating plate. Recommended operation is at the
mid--point of rise range or slightly above.
f. Proceed to “Set Blower Off Delay” before installing
blower door.
63
59MN7A
6. Re--check Minimum Heat Temperature Rise
To lock the furnace in Intermediate Heat:
1. Turn SW1--2 OFF and SW4--2 ON at the furnace control.
2. Connect a jumper across R and W/W1 at the thermostat
terminals at the furnace control.
3. Allow the burners to ignite and the blower to turn on.
4. Allow the supply temperature to stabilize and verify the
proper rise range.
If the temperature rise is too high or too low in Intermediate Heat:
1. Remove jumpers from R and W/W1.
2. Wait until the blower off delay is completed.
3. Turn 115 VAC power off.
4. Check the position of Set up switch SW1--3. When set to
ON, airflow is raised 18% for Minimum Heat and for
Intermediate Heat. Factory default position is OFF.
5. Turn 115 VAC power on.
6. Re--check Minimum Heat Temperature Rise .
To lock the furnace in Maximum Heat:
1. Connect a jumper across R and W/W1 and W2 at the
thermostat terminals at the furnace control.
2. Allow the burners to ignite and the blower to turn on.
3. Allow the supply temperature to stabilize and verify the
proper rise range.
If the temperature rise is too high or too low in Maximum Heat:
1. Remove jumpers from R and W/W1 and W2.
2. Wait until the blower off delay is completed.
3. Turn 115 VAC power off.
4. Check the position of Set up switch SW1--4. When set to
OFF, airflow is raised 10% for Minimum Heat, 7.5% for
Intermediate Heat and 17.5% for Maximum Heat. Factory
default position is ON.
5. Turn 115 VAC power on.
6. Re--check Minimum Heat Temperature Rise.
After the temperature rise has been verified:
1. Remove jumpers from thermostat terminals.
2. Allow the blower off delay to complete.
3. Turn Set up switches SW1--2 and SW4--2 to the OFF position.
4. Install blower door.
(6.) Turn SW1--2 switch OFF.
(7.) Install blower door.
b. Electronic thermostat: Set cycle rate for 3 cycles per hr.
MODULATING
ON/OFF Switch
Min/Max Heat Adust
(Under Cap)
59MN7A
Check Safety Controls
The flame sensor, gas valve, and pressure switch were all checked
in the Start--up procedure section as part of normal operation.
1. Check Main Limit Switch
This control shuts off combustion system and energizes air-circulating blower motor, if furnace overheats. By using this
method to check limit control, it can be established that limit is functioning properly and will operate if there is a restricted return--air supply or motor failure. If limit control
does not function during this test, cause must be determined
and corrected.
a. Run furnace for at least 5 minutes.
b. Gradually block off return air with a piece of cardboard or
sheet metal until the limit trips.
c. Unblock return air to permit normal circulation.
d. Burners will re--light when furnace cools down.
2. Check Pressure Switch(es)
This control proves operation of the draft inducer blower.
a. Turn off 115--v power to furnace.
b. Disconnect inducer motor lead wires from wire harness.
c. Turn on 115--v power to furnace.
d. Set thermostat to “call for heat” and wait 1 minute. When
pressure switch is functioning properly, hot surface igniter
should NOT glow and control diagnostic light flashes a
status code 32. If hot surface igniter glows when inducer
motor is disconnected, shut down furnace immediately.
e. Determine reason pressure switch did not function properly and correct condition.
f. Turn off 115--v power to furnace.
g. Reconnect inducer motor wires, replace blower door, and
turn on 115--v power.
h. Blower will run for 90 seconds before beginning the call
for heat again.
i. Furnace should ignite normally.
Turn screw 1 click per
second to adjust rate.
Clockwise to increase
rate, counter clockwise
to decrease rate.
Inlet
Pressure Tap
GA
SF
LO
W
1/2” NPT Outlet
Manifold
Pressure Tap
A10496
Fig. 50 -- Gas Valve
BURNER
ORIFICE
Checklist
1. Put away tools and instruments. Clean up debris.
2. Verify that switches SW1--1 and SW1--6 are OFF and other
setup switches are set as desired. Verify that switches
SW1--7 and SW1--8 for the blower OFF DELAY are set as
desired per Table 17.
3. Verify that blower and control doors are properly installed.
4. Cycle test furnace with room thermostat.
5. Check operation of accessories per manufacturer’s instructions.
6. Review Owner’s Manual with owner.
7. Attach literature packet to furnace.
A93059
Fig. 51 -- Orifice Hole
THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
(ANITICIPATOR, CLOCK, ETC.,
MUST BE OUT OF CIRCUIT.)
HOOK-AROUND
AMMETER
R Y W G
10 TURNS
FROM UNIT 24-V
CONTROL TERMINALS
EXAMPLE: 5.0 AMPS ON AMMETER
10 TURNS AROUND JAWS
= 0.5 AMPS FOR THERMOSTAT
ANTICIPATOR SETTING
A96316
Fig. 52 -- Amp. Draw Check with Ammeter
64
59MN7A
338307-201 Rev. F
A11594
Fig. 53 -- Service Label Information
65
59MN7A
A11623
Fig. 54 -- Furnace Setup Switches and Description
66
Furnace Setup Switch Description
SWITCH NAME
NORMAL POSITION
SW1-1
Status Code Recovery
OFF
SW1-2
Minimum Heat Only
(Adaptive Heat Mode
when SW1-2 and SW4-2
are OFF)
OFF
SW1-3
Min/Int Heat Rise
Adjustment
OFF
SW1-4
Comfort/Efficiency
Adjustment
ON
SW1-5
CFM per ton adjust
OFF
SW1-6
Component Self Test
OFF
SW1-7 & SW1-8
Blower OFF delay
ON or OFF
SW4-2
Intermendiate Heat
Only
(Adaptive Heat Mode
when both SW1-2 and
SW4-2 are OFF)
OFF
DESCRIPTION OF USE
Turn ON to retrieve up to 7 stored status codes for
troubleshooting assistance when R thermostat lead is
disconnected.
When SW1-2 and SW4-2 are OFF allows Modulating operation
with a single stage thermostat. Turn ON SW1-2 when using
two-stage thermostat to allow Minimum Heat operation when
R to W/W1 closed and a Maximum heat operation when R to
W/W1 and R to W2 close.
T
ON tto iincrease Mi
i
H
d IIntermediate
t
di t H
Turn
Minimum
Heatt and
Heatt
airflow by 18 percent. This compensates for increased return
air temperature caused with bypass humidifier. This also
increases the Intermediate Heat inducer speed 15 percent.
Turn ON to decrease Minimum heat airflow by 10 percent,
Intermediate Heat airflow 7.5 percent and Maximum Heat
airflow 17.5 percent for maximum comfort.
Turn ON for 400 CFM per ton, Turn OFF for 350 CFM per ton.
See also SW4.
Turn ON to initiate Component Self Test for troubleshooting
assistance when R thermostat lead is disconnected. Turn
OFF when Self Test is completed.
Bl
Blower
Off D
Delay
l time
i
– adjustable
dj
bl 90 seconds
d to 180
seconds. See table in Adjustments section or refer to unit
wiring diagram.
When SW1-2 and SW4-2 are OFF allows Modulating operation
with a single stage thermostat. Turn ON SW4-2 when using
two-stage thermostat to allow Intermediate Heat operation
when R to W/W1 closed and a Maximum heat operation when
R to W/W1 and R to W2 close.
Allows additional CFM per ton selections when used with SW
1-5
325 CFM per ton (nominal) when SW 4-3 ON and SW 1-5 OFF
350 CFM per ton (nominal) when SW 4-3 OFF and SW 1-5 OFF
SW4-3
CFM per ton Adjust
OFF
370 CFM per ton (nominal) when SW4-3 ON and SW 1-5 ON
400 CFM per ton (nominal) when SW 1-5 ON and SW 4-3 OFF
See Air Delivery Tables for model specific CFM vs. static
p
pressure
AIR CONDITIONING (A/C) SETUP SWITCHES
SW2
O1 2 3
N
1
AC
SW 2, AC (Cooling Airflow) SETUP SWITCHES
The AC setup switch selects desired cooling or high stage cooling (two stage units) airflow.
See Air Delivery Tables for specific switch settings
CONTINUOUS FAN (CF) SETUP SWITCHES
SW 3, CF (Continuous Fan) SETUP SWITCHES
SW3
O1 2 3
N
1
CF
The CF setup switch selects desired Continuous Fan Airflow
The CF switch position is the low cooling airflow selection for two stage cooling units.
The CFM values in the Air Delivery Tables for SW 3 settings are the same as SW 2 settings.
SW 3 cannot be set for airflow higher than SW 2
See Air Delivery Tables for specific switch settings
A11575 AMV
Fig. 54 -- Furnace Setup Switches and Description (Continued)
67
59MN7A
SETUP SWITCH
Table 17 – Blower Off Delay Setup Switch
Table 16 – Altitude Derate Multiplier for U.S.A.*
ALTITUDE
FT.
M
0–2000
2001–3000
3001–4000
4001–5000
5001–6000
6001–7000
7001–8000
8001–9000
9001–10,000
0---610
610---914
914---1219
1219---1524
1524---1829
1829---2134
2134---2438
2438---2743
2743---3048
PERCENT
OF
DERATE
0
4--- 6
6--- 8
8--- 10
10--- 12
12--- 14
14--- 16
16--- 18
18--- 20
DERATE
MULTIPLIER
FACTOR*
1.00
0.95
0.93
0.91
0.89
0.87
0.85
0.83
0.81
DESIRED HEATING MODE
BLOWER OFF DELAY (SEC.)
90
120
150
180
SETUP SWITCH
(SW1---7 AND ---8)
POSITION
SW1--- 7
SW1--- 8
OFF
OFF
ON
OFF
OFF
ON
ON
ON
*Derate multiplier factors are based on midpoint altitude for altitude range.
59MN7A
Table 18 – Gas Rate (CU ft./hr)
SECONDS
FOR 1 REVOLUTION
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
SIZE OF TEST DIAL
1 Cu Ft.
2 Cu Ft.
5 Cu Ft.
360
720
1800
327
655
1636
300
600
1500
277
555
1385
257
514
1286
240
480
1200
225
450
1125
212
424
1059
200
400
1000
189
379
947
180
360
900
171
343
857
164
327
818
157
313
783
150
300
750
144
288
720
138
277
692
133
267
667
129
257
643
124
248
621
120
240
600
116
232
581
113
225
563
109
218
545
106
212
529
103
206
514
100
200
500
97
195
486
95
189
474
92
185
462
90
180
450
88
176
439
86
172
429
84
167
419
82
164
409
80
160
400
78
157
391
76
153
383
75
150
375
73
147
367
SECONDS
FOR 1 REVOLUTION
50
51
52
53
54
55
56
57
58
59
60
62
64
66
68
70
72
74
76
78
80
82
84
86
88
90
92
94
96
98
100
102
104
106
108
110
112
116
120
68
SIZE OF TEST DIAL
1 Cu Ft.
2 Cu Ft.
5 Cu Ft.
72
144
360
71
141
355
69
138
346
68
136
340
67
133
333
65
131
327
64
129
321
63
126
316
62
124
310
61
122
305
60
120
300
58
116
290
56
112
281
54
109
273
53
106
265
51
103
257
50
100
250
48
97
243
47
95
237
46
92
231
45
90
225
44
88
220
43
86
214
42
84
209
41
82
205
40
80
200
39
78
196
38
76
192
38
75
188
37
74
184
36
72
180
35
71
178
35
69
173
34
68
170
33
67
167
33
65
164
32
64
161
31
62
155
30
60
150
Table 19 – Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate
To Be Used with Modulating Furnaces Except 59MN7A060V21--20
MODULATING FURNACE
(TABULATED DATA BASED ON 20,000 BTUH MAX-HEAT / 8,000 BTUH MIN-HEAT PER BURNER,
DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)
AVG. GAS
RANGE
HEAT VALUE
AT ALTITUDE
U.S.A. and Canada
ft (m)
U.S.A. and Canada
U.S.A. Only
U.S.A. Only
U.S.A. Only
0.60
0.62
0.64
Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press
(Btu/cu ft)
No.
Max/Min
No.
Max/Min
No.
Max/Min
No.
Max/Min
900
43
3.8 /0.60
42
3.2 /0.50
42
3.3 /0.55
42
3.4 /0.55
0
925
43
3.6 /0.55
43
3.7 /0.60
43
3.8 /0.60
42
3.2 /0.50
(0)
950
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.60
43
3.7 /0.60
975
44
3.7 /0.60
44
3.8 /0.60
43
3.4 /0.55
43
3.6 /0.55
1000
44
3.5 /0.55
44
3.6 /0.60
44
3.8 /0.60
43
3.4 /0.55
1025
44
3.3 /0.55
44
3.5 /0.55
44
3.6 /0.55
44
3.7 /0.60
1050
44
3.2 /0.50
44
3.3 /0.55
44
3.4 /0.55
44
3.5 /0.55
3.4 /0.55
to
2000
(610)
1075
45
3.7 /0.60
45
3.8 /0.60
44
3.3 /0.50
44
1100
46
3.7 /0.60
46
3.8 /0.60
45
3.8 /0.60
44
3.2 /0.50
800
42
3.4 /0.55
42
3.5 /0.55
42
3.6 /0.55
42
3.7 /0.60
2001 (611)
825
43
3.8 /0.60
42
3.3 /0.50
42
3.4 /0.55
42
3.5 /0.55
to
850
43
3.6 /0.60
43
3.7 /0.60
42
3.2 /0.50
42
3.3 /0.55
3000 (914)
875
43
3.4 /0.55
43
3.5 /0.55
43
3.7 /0.60
43
3.8 /0.60
900
44
3.7 /0.60
44
3.8 /0.60
43
3.5 /0.55
43
3.6 /0.55
Canada
925
44
3.5 /0.55
44
3.6 /0.60
44
3.8 /0.60
43
3.4 /0.55
2001 (611)
950
44
3.3 /0.55
44
3.4 /0.55
44
3.6 /0.55
44
3.7 /0.60
U.S.A.
U.S.A. Only
SPECIFIC GRAVITY OF NATURAL GAS
0.58
to
975
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
44
3.5 /0.55
4500 (1372)
1000
46
3.8 /0.60
45
3.8 /0.60
44
3.2 /0.50
44
3.3 /0.55
775
42
3.3 /0.55
42
3.4 /0.55
42
3.5 /0.55
42
3.6 /0.60
3001
800
43
3.8 /0.60
42
3.2 /0.50
42
3.3 /0.55
42
3.4 /0.55
(915)
825
43
3.6 /0.55
43
3.7 /0.60
43
3.8 /0.60
42
3.2 /0.50
850
44
3.8 /0.60
43
3.5 /0.55
43
3.6 /0.55
43
3.7 /0.60
875
44
3.6 /0.60
44
3.7 /0.60
43
3.4 /0.55
43
3.5 /0.55
4000
900
44
3.4 /0.55
44
3.5 /0.55
44
3.7 /0.60
44
3.8 /0.60
(1219)
925
44
3.2 /0.50
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.55
950
45
3.7 /0.60
44
3.2 /0.50
44
3.3 /0.55
44
3.4 /0.55
to
750
42
3.3 /0.50
42
3.4 /0.55
42
3.5 /0.55
42
3.6 /0.55
4001
775
43
3.7 /0.60
43
3.8 /0.60
42
3.3 /0.50
42
3.4 /0.55
(1220)
800
43
3.5 /0.55
43
3.6 /0.60
43
3.7 /0.60
43
3.8 /0.60
825
44
3.8 /0.60
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.60
850
44
3.5 /0.55
44
3.7 /0.60
44
3.8 /0.60
43
3.4 /0.55
5000
875
44
3.3 /0.55
44
3.5 /0.55
44
3.6 /0.55
44
3.7 /0.60
(1524)
900
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
44
3.5 /0.55
925
46
3.8 /0.60
45
3.7 /0.60
44
3.2 /0.50
44
3.3 /0.55
to
725
42
3.2 /0.50
42
3.3 /0.55
42
3.4 /0.55
42
3.5 /0.55
5001
750
43
3.7 /0.60
43
3.8 /0.60
42
3.2 /0.50
42
3.3 /0.55
(1525)
775
43
3.4 /0.55
43
3.5 /0.55
43
3.7 /0.60
43
3.8 /0.60
800
44
3.7 /0.60
44
3.8 /0.60
43
3.4 /0.55
43
3.5 /0.55
3.8 /0.60
to
825
44
3.5 /0.55
44
3.6 /0.55
44
3.7 /0.60
44
6000
850
44
3.3 /0.50
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.60
(1829)
875
45
3.7 /0.60
44
3.2 /0.50
44
3.3 /0.55
44
3.4 /0.55
900
46
3.7 /0.60
46
3.8 /0.60
45
3.8 /0.60
44
3.2 /0.50
675
42
3.4 /0.55
42
3.5 /0.55
42
3.6 /0.60
42
3.8 /0.60
6001
700
42
3.2 /0.50
42
3.3 /0.50
42
3.4 /0.55
42
3.5 /0.55
(1830)
725
43
3.6 /0.60
43
3.7 /0.60
43
3.8 /0.60
42
3.3 /0.50
750
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.55
43
3.7 /0.60
775
44
3.6 /0.60
44
3.7 /0.60
43
3.4 /0.55
43
3.5 /0.55
7000
800
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.60
44
3.7 /0.60
(2133)
825
44
3.2 /0.50
44
3.3 /0.55
44
3.4 /0.55
44
3.5 /0.55
850
46
3.8 /0.60
45
3.8 /0.60
44
3.2 /0.50
44
3.3 /0.55
to
59MN7A
ALTITUDE
A11251A
69
Table 19 -- Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate (Continued)
To Be Used with Modulating Furnaces Except 59MN7A060V21--20
MODULATING FURNACE
(TABULATED DATA BASED ON 20,000 BTUH MAX-HEAT / 8,000 BTUH MIN-HEAT PER BURNER,
DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)
ALTITUDE
AVG. GAS
RANGE
HEAT VALUE
AT ALTITUDE
U.S.A. Only
U.S.A. Only
59MN7A
U.S.A. Only
ft (m)
SPECIFIC GRAVITY OF NATURAL GAS
0.58
0.60
0.62
0.64
Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press
(Btu/cu ft)
No.
Max/Min
No.
Max/Min
No.
Max/Min
No.
Max/Min
650
42
3.4 /0.55
42
3.5 /0.55
42
3.6 /0.60
42
3.7 /0.60
7001
675
43
3.8 /0.60
42
3.2 /0.50
42
3.3 /0.55
42
3.4 /0.55
(2134)
700
43
3.5 /0.55
43
3.7 /0.60
43
3.8 /0.60
42
3.2 /0.50
725
44
3.8 /0.60
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.60
750
44
3.5 /0.55
44
3.7 /0.60
44
3.8 /0.60
43
3.4 /0.55
8000
775
44
3.3 /0.55
44
3.4 /0.55
44
3.5 /0.55
44
3.7 /0.60
(2438)
800
45
3.8 /0.60
44
3.2 /0.50
44
3.3 /0.55
44
3.4 /0.55
825
46
3.7 /0.60
46
3.8 /0.60
45
3.8 /0.60
44
3.2 /0.50
625
42
3.4 /0.55
42
3.5 /0.55
42
3.6 /0.55
42
3.7 /0.60
8001
650
43
3.8 /0.60
42
3.2 /0.50
42
3.3 /0.55
42
3.4 /0.55
(2439)
675
43
3.5 /0.55
43
3.6 /0.60
43
3.7 /0.60
42
3.2 /0.50
700
44
3.7 /0.60
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.55
725
44
3.5 /0.55
44
3.6 /0.60
44
3.7 /0.60
44
3.8 /0.60
9000
750
44
3.3 /0.50
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.55
(2743)
775
45
3.7 /0.60
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
9001
600
42
3.3 /0.55
42
3.4 /0.55
42
3.6 /0.55
42
3.7 /0.60
(2744)
625
43
3.7 /0.60
42
3.2 /0.50
42
3.3 /0.55
42
3.4 /0.55
650
43
3.5 /0.55
43
3.6 /0.55
43
3.7 /0.60
43
3.8 /0.60
675
44
3.7 /0.60
44
3.8 /0.60
43
3.4 /0.55
43
3.5 /0.55
10000
700
44
3.4 /0.55
44
3.5 /0.55
44
3.7 /0.60
44
3.8 /0.60
(3048)
725
44
3.2 /0.50
44
3.3 /0.55
44
3.4 /0.55
44
3.5 /0.55
to
to
to
* Orifice numbers shown in BOLD are factory-installed.
A11251B
70
Table 20 – Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate
To Be Used with Modulating Furnaces 59MN7A060V21--20 Only
(TABULATED DATA BASED ON 20,200 BTUH MAX-HEAT / 8,000 BTUH MIN-HEAT PER BURNER,
DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)
AVG. GAS
RANGE
HEAT VALUE
AT ALTITUDE
U.S.A. Only
U.S.A. Only
U.S.A. Only
U.S.A. Only
U.S.A. and Canada
U.S.A. and Canada
ft (m)
SPECIFIC GRAVITY OF NATURAL GAS
0.58
0.60
0.62
0.64
Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press
(Btu/cu ft)
No.
Max/Min
No.
Max/Min
No.
Max/Min
No.
Max/Min
900
42
3.2 /0.50
42
3.3 /0.50
42
3.4 /0.55
42
3.5 /0.55
0
925
43
3.7 /0.55
43
3.8 /0.60
42
3.2 /0.50
42
3.3 /0.50
(0)
950
43
3.5 /0.55
43
3.6 /0.55
43
3.7 /0.60
43
3.8 /0.60
975
44
3.8 /0.60
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.55
1000
44
3.6 /0.55
44
3.7 /0.60
44
3.8 /0.60
43
3.5 /0.55
1025
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.55
44
3.8 /0.60
1050
44
3.3 /0.50
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.55
to
2000
(610)
1075
45
3.8 /0.60
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
1100
46
3.8 /0.60
45
3.7 /0.60
44
3.2 /0.50
44
3.3 /0.50
U.S.A.
800
42
3.4 /0.55
42
3.5 /0.55
42
3.7 /0.55
42
3.8 /0.60
2001 (611)
825
42
3.2 /0.50
42
3.3 /0.50
42
3.4 /0.55
42
3.6 /0.55
to
850
43
3.7 /0.60
43
3.8 /0.60
42
3.2 /0.50
42
3.3 /0.55
3000 (914)
875
43
3.5 /0.55
43
3.6 /0.55
43
3.7 /0.60
43
3.8 /0.60
900
44
3.8 /0.60
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.55
Canada
925
44
3.6 /0.55
44
3.7 /0.60
44
3.8 /0.60
43
3.4 /0.55
2001 (611)
950
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.55
44
3.7 /0.60
3.6 /0.55
to
975
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
44
4500 (1372)
1000
45
3.7 /0.60
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
775
42
3.4 /0.55
42
3.5 /0.55
42
3.6 /0.55
42
3.7 /0.60
3001
800
42
3.2 /0.50
42
3.3 /0.50
42
3.4 /0.55
42
3.5 /0.55
(915)
825
43
3.6 /0.55
43
3.7 /0.60
42
3.2 /0.50
42
3.3 /0.50
850
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.55
43
3.8 /0.60
to
875
44
3.7 /0.60
44
3.8 /0.60
43
3.4 /0.55
43
3.6 /0.55
4000
900
44
3.5 /0.55
44
3.6 /0.55
44
3.7 /0.60
43
3.4 /0.55
(1219)
925
44
3.3 /0.50
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.55
950
45
3.8 /0.60
44
3.2 /0.50
44
3.4 /0.55
44
3.5 /0.55
750
42
3.3 /0.50
42
3.4 /0.55
42
3.6 /0.55
42
3.7 /0.55
4001
775
43
3.8 /0.60
42
3.2 /0.50
42
3.3 /0.50
42
3.4 /0.55
(1220)
800
43
3.6 /0.55
43
3.7 /0.60
43
3.8 /0.60
42
3.2 /0.50
825
44
3.8 /0.60
43
3.5 /0.55
43
3.6 /0.55
43
3.7 /0.60
850
44
3.6 /0.55
44
3.7 /0.60
43
3.4 /0.55
43
3.5 /0.55
5000
875
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.55
44
3.8 /0.60
(1524)
900
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
44
3.6 /0.55
925
45
3.7 /0.60
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
to
725
42
3.3 /0.50
42
3.4 /0.55
42
3.5 /0.55
42
3.6 /0.55
5001
750
43
3.7 /0.60
42
3.2 /0.50
42
3.3 /0.50
42
3.4 /0.55
(1525)
775
43
3.5 /0.55
43
3.6 /0.55
43
3.7 /0.60
42
3.2 /0.50
800
44
3.8 /0.60
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.55
825
44
3.5 /0.55
44
3.7 /0.55
44
3.8 /0.60
43
3.4 /0.55
6000
850
44
3.3 /0.50
44
3.4 /0.55
44
3.6 /0.55
44
3.7 /0.60
(1829)
875
45
3.8 /0.60
44
3.3 /0.50
44
3.4 /0.55
44
3.5 /0.55
900
46
3.8 /0.60
45
3.7 /0.60
44
3.2 /0.50
44
3.3 /0.50
675
42
3.5 /0.55
42
3.6 /0.55
42
3.7 /0.60
42
3.8 /0.60
6001
700
42
3.2 /0.50
42
3.3 /0.50
42
3.5 /0.55
42
3.6 /0.55
(1830)
725
43
3.7 /0.60
43
3.8 /0.60
42
3.2 /0.50
42
3.3 /0.50
750
43
3.4 /0.55
43
3.5 /0.55
43
3.7 /0.55
43
3.8 /0.60
775
44
3.7 /0.60
44
3.8 /0.60
43
3.4 /0.55
43
3.5 /0.55
7000
800
44
3.5 /0.55
44
3.6 /0.55
44
3.7 /0.60
44
3.8 /0.60
(2133)
825
44
3.2 /0.50
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.55
850
45
3.7 /0.60
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
to
to
59MN7A
ALTITUDE
A11621A
71
Table 20 -- Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate (Continued)
To Be Used with Modulating Furnaces 59MN7A060V21--20 Only
(TABULATED DATA BASED ON 20,200 BTUH MAX-HEAT / 8,000 BTUH MIN-HEAT PER BURNER,
DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)
ALTITUDE
AVG. GAS
RANGE
HEAT VALUE
AT ALTITUDE
U.S.A. Only
U.S.A. Only
59MN7A
U.S.A. Only
ft (m)
SPECIFIC GRAVITY OF NATURAL GAS
0.58
0.60
0.62
0.64
Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press
(Btu/cu ft)
No.
Max/Min
No.
Max/Min
No.
Max/Min
No.
Max/Min
650
42
3.4 /0.55
42
3.6 /0.55
42
3.7 /0.60
42
3.8 /0.60
7001
675
42
3.2 /0.50
42
3.3 /0.50
42
3.4 /0.55
42
3.5 /0.55
(2134)
700
43
3.6 /0.55
43
3.7 /0.60
42
3.2 /0.50
42
3.3 /0.50
725
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.55
43
3.7 /0.60
750
44
3.6 /0.55
44
3.7 /0.60
43
3.4 /0.55
43
3.5 /0.55
8000
775
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.55
44
3.7 /0.60
(2438)
800
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
44
3.5 /0.55
825
46
3.8 /0.60
45
3.7 /0.60
44
3.2 /0.50
44
3.3 /0.50
to
625
42
3.4 /0.55
42
3.5 /0.55
42
3.7 /0.55
42
3.8 /0.60
8001
650
42
3.2 /0.50
42
3.3 /0.50
42
3.4 /0.55
42
3.5 /0.55
(2439)
675
43
3.6 /0.55
43
3.7 /0.60
43
3.8 /0.60
42
3.2 /0.50
700
44
3.8 /0.60
43
3.4 /0.55
43
3.6 /0.55
43
3.7 /0.55
725
44
3.6 /0.55
44
3.7 /0.60
44
3.8 /0.60
43
3.4 /0.55
9000
750
44
3.3 /0.50
44
3.4 /0.55
44
3.5 /0.55
44
3.7 /0.55
(2743)
775
45
3.8 /0.60
44
3.2 /0.50
44
3.3 /0.50
44
3.4 /0.55
9001
600
42
3.4 /0.55
42
3.5 /0.55
42
3.6 /0.55
42
3.8 /0.60
(2744)
625
43
3.8 /0.60
42
3.2 /0.50
42
3.3 /0.55
42
3.5 /0.55
650
43
3.5 /0.55
43
3.6 /0.55
43
3.8 /0.60
42
3.2 /0.50
675
44
3.8 /0.60
43
3.4 /0.55
43
3.5 /0.55
43
3.6 /0.55
10000
700
44
3.5 /0.55
44
3.6 /0.55
44
3.7 /0.60
44
3.8 /0.60
(3048)
725
44
3.3 /0.50
44
3.4 /0.55
44
3.5 /0.55
44
3.6 /0.55
to
to
* Orifice numbers shown in BOLD are factory-installed.
A11621B
72
!
Electrical Controls and Wiring
!
WARNING
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury
or death.
FIRE, INJURY OR DEATH HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
The ability to properly perform maintenance on this
equipment requires certain knowledge, mechanical skills,
tools, and equipment. If you do not possess these, do not
attempt to perform any service and maintenance on this
equipment other than those procedures recommended in the
Owner’s Manual.
!
CAUTION
ENVIRONMENTAL HAZARD
Failure to follow this caution may result in environmental
pollution.
Remove and recycle all components or materials (i.e. oil,
refrigerant, control board, etc.) before unit final disposal.
WARNING
There may be more than one electrical supply to the furnace.
Check accessories and cooling unit for additional electrical
supplies that must be shut off during furnace servicing. Lock
out and tag switch with a suitable warning label.
The electrical ground and polarity for 115--v wiring must be
properly maintained. Refer to Fig. 33 for field wiring information
and to Fig. 63 for furnace wiring information.
NOTE: If the polarity is not correct, the STATUS LED on the
control will flash rapidly and prevent the furnace from heating. The
control system also requires an earth ground for proper operation
of the control and flame--sensing electrode.
The 24--v circuit contains an automotive--type, 3--amp. fuse located
on the control. (See Fig. 34.) Any shorts of the 24--v wiring during
installation, service, or maintenance will cause this fuse to blow. If
fuse replacement is required, use ONLY a 3--amp. fuse. The control
LED will display status code 24 when fuse needs to be replaced.
Troubleshooting
!
WARNING
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow this warning could result in personal
injury or death, or property damage.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag. There may be more than one
disconnect switch. Lock out and tag switch with a suitable
warning label. Verify proper operation after servicing.
!
CAUTION
Refer to the service label. (See Fig. 53—Service Label.)
The Troubleshooting Guide (See Fig. 62) can be a useful tool in
isolating furnace operation problems. Beginning with the word
“Start,” answer each question and follow the appropriate arrow to
the next item.
The Guide will help to identify the problem or failed component.
After replacing any component, verify correct operation sequence.
Proper instrumentation is required to service electrical controls.
The control in this furnace is equipped with a Status Code LED
(Light--Emitting Diode) to aid in installation, servicing, and
troubleshooting. Status codes can be viewed at the indicator in
blower door. The amber furnace control LED is either ON
continuously, rapid flashing, or a code composed of 2 digits. The
first digit is the number of short flashes, the second digit is the
number of long flashes.
For an explanation of status codes, refer to service label located on
control door or Fig. 53, and the troubleshooting guide which can
be obtained from your distributor.
ELECTRICAL OPERATION HAZARD
Retrieving Stored Fault Codes
Failure to follow this caution may result in improper
furnace operation or failure of furnace.
The stored status codes will NOT be erased from the control
memory, when 115-- or 24--v power is interrupted. The control will
store up to the last 7 Status Codes in order of occurrence.
1. To retrieve status codes, proceed with the following:
NOTE: NO thermostat signal may be present at control, and all
blower--OFF delays must be completed.
a. Leave 115--v power to furnace turned on.
b. Look into blower door indicator for current LED status.
c. Remove blower door.
NOTE: The Status Codes cannot be retrieved by disconnecting
the limit switch. To retrieve Status Codes, follow the procedure
below.
Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and dangerous
operation.
General
These instructions are written as if the furnace is installed in an
upflow application. An upflow furnace application is where the
blower is located below the combustion and controls section of the
furnace, and conditioned air is discharged upward. Since this
furnace can be installed in any of the 4 positions shown in Fig. 2,
you must revise your orientation to component location
accordingly.
73
59MN7A
SERVICE AND MAINTENANCE
PROCEDURES
2.
3.
4.
5.
6.
7.
Turn Setup Switch, SW1--1 “ON.”
Manually close blower door switch.
Control will flash up to 7 Status Codes.
The last Status Code, or 8th Code, will be Code 11.
Turn SW1--1 “OFF.”
A continuously--lit Amber LED will appear and indicates
proper operation.
8. Release blower door switch, install blower door and refer
to the SERVICE label on the control door for more information.
Care and Maintenance
!
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
Never store flammable or combustible materials on, near, or
in contact with the furnace, such as:
1. Spray or aerosol cans, rags, brooms, dust mops,
vacuum cleaners, or other cleaning tools.
2. Soap powders, bleaches, waxes or other cleaning
compounds, plastic or plastic containers, gasoline,
kerosene, cigarette lighter fluid, dry cleaning fluids,
or other volatile fluids.
3. Paint thinners and other painting compounds, paper
bags, or other paper products. Exposure to these
materials could lead to corrosion of the heat
exchangers.
59MN7A
Component Self-- Test
Component Test can ONLY be initiated by performing the
following:
1. Remove blower door.
2. Remove the wire from the “R” terminal of the control
board.
3. Turn Setup Switch, SW--1--6 “ON.”
4. Manually close blower door switch.
Blower door switch opens 115--v power to control. No component
operation can occur unless switch is closed. Caution must be taken
when manually closing this switch for service purposes.
!
WARNING
For continuing high performance and to minimize possible furnace
failure, periodic maintenance must be performed on this furnace.
Consult your local dealer about proper frequency of maintenance
and the availability of a maintenance contract.
!
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal injury,
or death.
WARNING
ELECTRICAL SHOCK AND FIRE HAZARD
Failure to follow this warning could result in personal injury,
death, and/or property damage.
Blower door switch opens 115--v power to furnace control.
No component operation can occur unless switch is closed.
Exercise caution to avoid electrical shock from exposed
electrical components when manually closing this switch for
service purposes.
5. Component Test sequence will function as follows:
a. The furnace control CPU turns the inducer motor IDM ON
at medium speed and keeps it ON through Step d.
b. The furnace control CPU will test communication with the
modulating gas valve GV.
c. After waiting 15 seconds the furnace control CPU turns the
hot surface igniter ON for 15 seconds, then OFF.
d. The furnace control CPU then turns the blower motor
BLWM ON at mid-range airflow for 15 seconds, then OFF.
e. After shutting the blower motor BLWM OFF the furnace
control CPU shuts the inducer motor IDM OFF.
NOTE: The EAC terminals are energized when the blower is
operating.
After the component test is completed, 1 or more status codes (11,
25, 35, 41, or 42) will flash. See Service Label on control door or
Service/Status Code Instructions for explanation of status codes.
NOTE: To repeat component test, turn setup switch SW1-6 to
OFF and then back ON.
f. Turn setup switch SW1--6 OFF.
6. RELEASE BLOWER DOOR SWITCH, reattach wire to
“R” terminal on furnace control board and replace blower
door.
WARNING
Turn off the gas and electrical supplies to the furnace and
install lockout tag before performing any maintenance or
service. Follow the operating instructions on the label
attached to the furnace.
!
WARNING
CARBON MONOXIDE POISONING AND FIRE
HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
Never operate furnace without a filter or filtration device
installed. Never operate a furnace with filter or filtration
device access doors removed.
!
CAUTION
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care
and wear appropriate protective clothing, safety glasses and
gloves when handling parts, and servicing furnaces.
The minimum maintenance on this furnace is as follows:
1. Check and clean air filter each month or more frequently if
required. Replace if torn.
2. Check blower motor and wheel for cleanliness each heating
and cooling season. Clean as necessary.
3. Check electrical connections for tightness and controls for
proper operation each heating season. Service as necessary.
74
Cleaning and/or Replacing Air Filter
The air filter type may vary depending on the application or
orientation. The filter is external to the furnace casing. There are no
provisions for an internal filter with this furnace. See “Filter
Arrangement” under the “Installation” section of this manual.
!
WARNING
CARBON MONOXIDE POISONING AND FIRE
HAZARD
Failure to follow this warning could result in personal
injury, death and/or property damage.
Never operate furnace without a filter or filtration device
installed. Never operate a furnace with filter or filtration
device access doors removed.
NOTE: If the filter has an airflow direction arrow, the arrow must
point toward the blower.
To clean or replace filters, proceed as follows:
!
WARNING
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow this warning could result in personal
injury or death, or property damage.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag. There may be more than one
disconnect switch. Lock out and tag switch with a suitable
warning label. Verify proper operation after servicing.
1.
2.
3.
4.
5.
6.
7.
8.
Turn off electrical supply to furnace.
Remove filter cabinet door.
Slide filter out of cabinet.
If equipped with permanent, washable filter, clean filter by
spraying cold tap water through filter in opposite direction
of airflow. Rinse filter and let dry. Oiling or coating of the
filter is not recommended.
If equipped with factory specified disposable media filter,
replace only with a factory specified media filter of the same
size.
Slide filter into cabinet.
Replace filter cabinet door.
Turn on electrical supply to furnace.
Blower Motor and Wheel Maintenance
To ensure long life, economy, and high efficiency, clean
accumulated dirt and grease from blower wheel and motor
annually.
The inducer and blower motors are pre--lubricated and require no
additional lubrication. These motors can be identified by the
absence of oil ports on each end of the motor.
The following items should be performed by a qualified service
technician. Clean blower motor and wheel as follows:
1. Turn off electrical supply to furnace.
2. Remove blower door.
3. All factory wires can be left connected, but field thermostat
and accessory wiring may need to be disconnected depending on their length and routing.
4. If the vent and combustion air pipe passes through the
blower compartment, it will be necessary to remove the
pipes from the blower compartment.
Disconnect the vent and combustion air pipe by:
a. Loosen the clamps on the vent couplings and combustion
air pipe external to the furnace.
b. Separate the pipes from the couplings and move them
aside.
c. Loosen the clamps on the vent couplings and combustion
air pipe located on the blower shelf.
d. Separate the pipes from the blower compartment and set
aside.
e. Remove the couplings from the pipe adapters and set aside.
f. After servicing the blower, reverse steps a through e.
g. Tighten all clamps 15 lb --in.
See Fig. 60 For Steps 5 through 14.
5. Remove screws securing blower assembly to blower shelf
and slide blower assembly out of furnace. Detach ground
wire and disconnect blower motor harness plugs from
blower motor.
NOTE: Blower wheel is fragile. Use care.
6. Clean blower wheel and motor by using a vacuum with soft
brush attachment. Be careful not to disturb balance weights
(clips) on blower wheel vanes. Do not bend wheel or blades
as balance will be affected.
7. If greasy residue is present on blower wheel, remove wheel
from the blower housing and wash it with an appropriate
degreaser. To remove wheel:
a. Mark blower wheel location on shaft before disassembly
to ensure proper reassembly.
b. Loosen setscrew holding blower wheel on motor shaft.
NOTE: Mark blower mounting arms and blower housing so each
arm is positioned at the same hole location during reassembly.
c. Mark blower wheel orientation and cutoff plate location to
ensure proper reassembly.
d. Remove screws securing cutoff plate and remove cutoff
plate from housing.
e. Remove bolts holding motor mounts to blower housing
and slide motor and mounts out of housing.
f. Remove blower wheel from housing.
g. Clean wheel per instructions on degreaser cleaner. Do not
get degreaser in motor.
8. Reassemble motor and blower wheel by reversing items 7b
through 7f. Ensure wheel is positioned for proper rotation.
9. Torque motor mounting bolts to 40 +/-- 10 lb--in. when reassembling.
10. Torque blower wheel set screw to 160 +/-- 20 lb--in. when
reassembling.
11. Verify that blower wheel is centered in blower housing and
set screw contacts the flat portion of the motor shaft. Loosen
set screw on blower wheel and reposition if necessary.
12. Spin the blower wheel by hand to verify that the wheel does
not rub on the housing.
13. Reinstall blower assembly in furnace.
14. Reinstall 2 screws securing blower assembly to blower
deck.
75
59MN7A
4. Inspect burner compartment before each heating season for
rust, corrosion, soot or excessive dust. If necessary, have
furnace and burner serviced by a qualified service agency.
5. Inspect the vent pipe/vent system before each heating season for water leakage, sagging pipes or broken fittings.
Have vent pipes/vent system serviced by a qualified service
agency.
6. Inspect any accessories attached to the furnace such as a humidifier or electronic air cleaner. Perform any service or
maintenance to the accessories as recommended in the accessory instructions.
15. Reconnect blower leads to furnace control. Refer to furnace
wiring diagram, and connect thermostat leads if previously
disconnected.
NOTE: Be sure to attach ground wire and reconnect blower
harness plugs to blower motor.
!
WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
59MN7A
Blower door switch opens 115--v power to control. No
component operation can occur unless switch is closed.
Caution must be taken when manually closing this switch for
service purposes.
16. Downflow or horizontal furnaces with vent pipe through
furnace only:
a. Install and connect short piece of vent pipe inside furnace
to existing vent.
b. Connect vent connector to vent elbow.
17. Turn on electrical supply. If outdoor temperature is below
70_F, turn off circuit breaker to outdoor unit before running
furnace in the cooling cycle. Turn outdoor circuit breaker
on after completing cooling cycle. (See Fig. 34.) Manually
close blower door switch. Use a piece of tape to hold switch
closed. Check for proper rotation and speed changes
between heating and cooling by jumpering R to G and R to
Y/Y2 on furnace control thermostat terminals.
NOTE: If R--W/W1 thermostat terminals are jumpered at the time
blower door switch is closed, blower will run for 90 sec before
beginning a heating cycle.
a. Perform component self--test as shown at the bottom of the
SERVICE label, located on the control door.
b. Verify blower is rotating in the correct direction
18. If furnace is operating properly, RELEASE BLOWER
DOOR SWITCH. Remove any jumpers or reconnect any
disconnected thermostat leads. Replace blower door.
19. Turn on gas supply and cycle furnace through one complete
heating cycle. Verify the furnace temperature rise as shown
in Adjustments Section. Adjust temperature rise as shown in
Adjustments Section.
Cleaning Burners and Flame Sensor
The following items must be performed by a qualified service
technician. If the burners develop an accumulation of light dirt or
dust, they may be cleaned by using the following procedure:
NOTE: Use a back-up wrench on the gas valve to prevent the
valve from rotating on the manifold or damaging the mounting to
the burner assembly.
!
WARNING
ELECTRICAL SHOCK AND FIRE HAZARD
Failure to follow this warning could result in personal injury,
death, and/or property damage.
Turn off the gas and electrical supplies to the furnace and
install lockout tag before performing any maintenance or
service. Follow the operating instructions on the label
attached to the furnace.
Refer to Fig. 61.
1. Disconnect power at external disconnect, fuse or circuit
breaker.
2.
3.
4.
5.
Turn off gas at external shut-off or gas meter.
Remove control door and set aside.
Turn electric switch on gas valve to OFF.
Disconnect the gas pipe from gas valve and remove pipe
from the furnace casing.
6. Disconnect the connector harness from gas valve (Modulating only) or remove individual wires from terminals on gas
valve (All other models).
7. Disconnect Hot Surface Igniter (HSI) wires from HSI.
8. Disconnect Flame Sensor wire from Flame Sensor.
9. Support the manifold and remove the 4 screws that secure
the manifold assembly to the burner assembly and set aside.
Note the location of the green/yellow wire and ground terminal.
10. Inspect the orifices in the manifold assembly for blockages
or obstructions. Remove orifice and clean or replace orifice.
11. Remove the four screws that attach the top plate of the casing to the furnace.
12. Raise top plate up slightly and prop it up with a small piece
of wood or folded cardboard.
13. Support the burner assembly and remove the screws that attach the burner assembly to the heat exchanger cell panel.
14. Remove wires from both rollout switches.
15. Slide one--piece burner out of slots on sides of burner assembly.
16. Remove the flame sensor from the burner assembly.
17. (Optional) Remove the Hot Surface Igniter (HSI) and
bracket from the burner assembly.
18. Check igniter resistance. Nominal resistance is 40 to 70
ohms at room temperature and is stable over the life of the
igniter.
19. Clean burner with a brush and a vacuum.
20. Clean the flame sensor with fine steel wool (0000 grade).
Do not use sand paper or emery cloth.
To reinstall burner assembly:
1. Install the Hot Surface Igniter (HSI) and bracket in burner
assembly.
2. Install flame sensor on burner.
3. Align the edges of the one-piece burner with the slots in the
burner assembly and slide the burners forward until they are
fully seated in the burner assembly.
4. Align the orifices in the manifold assembly with the support
rings on the end of the burner.
5. Insert the orifices in the support rings of the burners.
NOTE: If manifold does not fit flush against the burner, do not
force the manifold on the burner assembly. The burners are not
fully seated forward in the burner assembly. Remove the manifold
and check burner positioning in the burner assembly assembly
before re-installing the manifold.
6. Attach the green/yellow wire and ground terminal to one of
the manifold mounting screws.
7. Install the remaining manifold mounting screws.
8. Check the igniter alignment. See Fig. 55, 56 and 61.
9. Attach the wires to the roll-out switches.
10. Align the burner assembly with the openings in the primary
cell inlet panel and attach the burner assembly to the cell
panel.
11. Connect the wire for the flame sensor.
12. Connect the wire for the Hot Surface Igniter.
NOTE: Use propane-resistant pipe dope to prevent leaks. Do not
use Teflon tape.
13. Install the gas pipe to the gas valve.
76
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Never purge a gas line into a combustion chamber. Never
test for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection
of leaks to check all connections. A fire or explosion may
result causing property damage, personal injury or loss of
life.
14. Check for gas leaks with a commercially available soap
solution made specifically for the detection of leaks.
15. Turn gas on at electric switch on gas valve and at external
shut-off or meter
16. Turn power on at external disconnect, fuse or circuit breaker.
17. Run the furnace through two complete heating cycles to
check for proper operation
18. Install control door when complete.
Servicing Hot Surface Igniter
The igniter does NOT require annual inspection. Check igniter
resistance before removal. Refer to Fig. 55, 56 and 61.
1. Turn off gas and electrical supplies to furnace.
2. Remove control door.
3. Disconnect igniter wire connection.
4. Check igniter resistance. Igniter resistance is affected by
temperature. Only check resistance when the igniter is at
room temperature.
a. Using an ohm meter, check resistance across both igniter
leads in connector.
b. Cold reading should be between 40 ohms and 70 ohms.
Resistance reading will increase as igniter temperature
increases.
5. Remove igniter assembly.
a. Using a 1/4--in. driver, remove the two screws securing the
igniter mounting bracket to the burner assembly (See Fig.
61 .)
b. Carefully withdraw the igniter and bracket assembly
through the front of the burner assembly without striking
the igniter on surrounding parts.
c. Inspect igniter for signs of damage or failure.
d. If replacement is required, remove the screw that secures
the igniter on igniter bracket and remove the igniter.
6. To replace igniter and bracket assembly, reverse items 5a
through 5d.
7. Reconnect igniter harness to the igniter, dressing the igniter
wires to ensure there is no tension on the igniter itself. (See
Fig. 61.)
8. Turn on gas and electrical supplies to furnace.
9. Verify igniter operation by initiating control board self--test
feature or by cycling thermostat.
10. Replace control door.
Flushing Collector Box and Drainage System
!
WARNING
ELECTRICAL SHOCK AND FIRE HAZARD
Failure to follow this warning could result in personal injury,
death, and/or property damage.
Turn off the gas and electrical supplies to the furnace and
install lockout tag before performing any maintenance or
service. Follow the operating instructions on the label
attached to the furnace.
Cleaning Condensate Drain and Trap
NOTE: If the condensate trap is removed, a new gasket between
the trap and collector box is required. Verify a condensate trap
gasket is included in the service kit or obtain one from your local
distributor.
1. Disconnect power at external disconnect, fuse or circuit
breaker.
2. Turn off gas at external shut-off or gas meter.
3. Remove control door and set aside.
4. Turn electric switch on gas valve to OFF.
5. Disconnect external drain from condensate drain elbow or
drain extension pipe inside the furnace and set aside.
6. Disconnect the condensate trap relief hose from collector
box port and condensate trap.
NOTE: If condensate has a heat pad attached to the trap, trace the
wires for the pad back to the connection point and disconnect the
wires for the heat pad.
7. Remove the screw that secures the condensate trap to the
collector box, remove the trap and set aside.
8. Remove the trap gasket from the collector box if it did not
come off when the trap was removed.
9. Discard the old trap gasket.
10. Rinse condensate trap in warm water until trap is clean.
11. Flush condensate drain lines with warm water. Remember
to check and clean the relief port on the collector box.
12. Shake trap dry.
13. Clean port on collector box with a small wire.
To re-install Condensate Drain and Trap:
1. Remove adhesive backing from condensate trap gasket
2. Install gasket on collector box
3. Align the condensate trap with the drain opening on the collector box and secure the trap with the screw
4. Attach the relief hose to the relief port on the condensate
trap and collector box.
5. Secure tubing to prevent any sags or traps in the tubing.
6. Connect condensate drain elbow or drain extension elbow
to the condensate trap
7. Connect the leads of the condensate heat pad (if used)
8. Connect external drain piping to the condensate drain elbow
or drain extension pipe.
9. Turn gas on at electric switch on gas valve and at external
shut-off or meter
77
59MN7A
WARNING
FIRE OR !EXPLOSION HAZARD
1. Turn off gas and electrical supplies to furnace.
2. Remove control door.
3. Disconnect pressure switch tube from pressure switch port.
NOTE: Ensure the pressure switch tube disconnected from the
pressure switch is higher than the collector box opening or water
will flow out of tube.
4. Remove the collector box plug from the top port on the upper corner of the collector box. (See Fig. 57)
5. Attach a funnel with a flexible tube to port on the collector
box.
6. Flush inside of collector box with water until discharge
water from condensate trap is clean and runs freely.
7. Repeat steps 4 thru 6 with middle plug on upper corner of
collector box.
8. Remove the pressure switch tube from the collector box.
NOTE: Do NOT blow into tube with tube connected to the
pressure switch.
9. Clean pressure switch port on collect box with a small wire.
Shake any water out of pressure switch tube.
10. Reconnect tube to pressure switch and pressure switch port.
11. Remove the relief tube from the port on the collector box
and the trap.
12. Clean the relief port on collect box and the trap with a small
wire. Shake any water out of the tube.
13. Reconnect relief tube to trap and collector box ports.
10. Turn power on at external disconnect, fuse or circuit breaker.
11. Run the furnace through two complete heating cycles to
check for proper operation
12. Install control door when complete.
59MN7A
Checking Heat Pad Operation (If Applicable)
In applications where the ambient temperature around the furnace
is 32_F or lower, freeze protection measures are required. If this
application is where heat tape has been applied, check to ensure it
will operate when low temperatures are present.
NOTE: The Heat Pad, when used, should be wrapped around the
condensate drain trap. There is no need to use heat tape within the
furnace casing. Most heat tapes are temperature activated, and it is
not practical to verify the actual heating of the tape. Check the
following:
1. Check for signs of physical damage to heat tape such as
nicks, cuts, abrasions, gnawing by animals, etc.
2. Check for discolored heat tape insulation. If any damage or
discolored insulation is evident, replace heat tape.
3. Check that heat tape power supply circuit is on.
Cleaning Heat Exchangers
The following items must be performed by a qualified service
technician.
Primary Heat Exchangers
3. Disconnect wires or connectors to flame rollout switch, gas
valve, igniter, and flame sensor.
4. Using backup wrench, disconnect gas supply pipe from furnace gas control valve.
5. Remove two screws attaching top filler plate and rotate upwards to gain access to screws attaching burner assembly to
cell panel.
6. Remove screws attaching burner assembly to cell panel.
(See Fig. 61.)
NOTE: Burner cover, manifold, gas valve, and burner assembly
should be removed as one assembly.
7. Clean heat exchanger openings with a vacuum and a soft
brush. (See Fig. 58.)
NOTE: After cleaning, inspect the heat exchangers to ensure they
are free of all foreign objects that may restrict flow of combustion
products.
8. Reverse items 6 through 1 for reassembly.
9. Refer to furnace wiring diagram and reconnect wires to
flame rollout switch, gas valve, igniter, and flame sensor.
10. Turn on gas and electrical supplies to furnace.
11. Check furnace operation through 2 complete heat operating
cycles. Look at burners. Burner flames should be clear blue,
almost transparent. (See Fig. 59.)
12. Check for gas leaks.
If the heat exchangers get an accumulation of light dirt or dust on
the inside, they may be cleaned by the following procedure:
NOTE: If the heat exchangers get a heavy accumulation of soot
and carbon, both the primary and secondary heat exchangers
should be replaced rather than trying to clean them thoroughly due
to their intricate design. A build--up of soot and carbon indicates
that a problem exists which needs to be corrected, such as improper
adjustment of manifold pressure, insufficient or poor quality
combustion air, improper vent termination, incorrect size or
damaged manifold orifice(s), improper gas, or a restricted heat
exchanger (primary or secondary). Action must be taken to correct
the problem.
1. Turn off gas and electrical supplies to furnace.
!
WARNING
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow this warning could result in personal
injury or death, or property damage.
Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag. There may be more than one
disconnect switch. Lock out and tag switch with a suitable
warning label. Verify proper operation after servicing.
WARNING
!
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Never purge a gas line into a combustion chamber. Never
test for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection
of leaks to check all connections. A fire or explosion may
result causing property damage, personal injury or loss of
life.
13. Replace main furnace door.
Secondary Heat Exchangers
The condensing side (inside) of the secondary heat exchanger
CANNOT be serviced or inspected without complete removal of
the heat exchanger assembly. Detailed information on heat
exchanger removal can be obtained from your Distributor.
Wiring Diagrams
See Fig. 63 for the Deluxe 4--Way Multipoise Furnace wiring
diagrams.
WINTERIZATION
!
CAUTION
UNIT AND PROPERTY DAMAGE HAZARD
!
WARNING
Failure to follow this caution may result in unit component or
property damage.
If the furnace is installed in an unconditioned space where the
ambient temperatures may be 32_ F (0_ C) or lower, freeze
protection measures must be taken to prevent property or
product damage.
ELECTRICAL SHOCK AND FIRE HAZARD
Failure to follow this warning could result in personal injury,
death, and/or property damage.
Turn off the gas and electrical supplies to the furnace and
install lockout tag before performing any maintenance or
service. Follow the operating instructions on the label
attached to the furnace.
2. Remove control door.
Since the furnace uses a condensing heat exchanger, some water
will accumulate in the unit as a result of the heat transfer process.
Therefore, once it has been operated, it cannot be turned off and
left off for an extended period of time when temperatures will
reach 32_F (0_C) or lower unless winterized. Follow these
procedures to winterize your furnace:
78
!
CAUTION
UNIT COMPONENT DAMAGE HAZARD
Failure to follow this caution may result in damage to the
furnace and other property damage.
1. Obtain propylene glycol (RV/swimming pool antifreeze or
equivalent).
2. Turn off gas and electrical supplies to your furnace.
3. Remove furnace control door.
4. Remove the top unused rubber plug from the port on the
collector box opposite the condensate trap. See Fig. 57.
5. Connect a field supplied 3/8--in. (9.5--mm) ID tube to the
open port on the collector box
6. Insert a field supplied funnel into the tube.
7. Pour 1 quart of anti--freeze solution into the funnel/tube.
Antifreeze should run through the inducer housing, overfill
condensate trap and flow to an open drain.
8. Replace the rubber plug in the port on the collector box.
9. Remove the middle unused rubber plug from the port on the
collector box opposite the condensate trap. See Fig. 57
10. Repeat Steps 5 through 8.
11. If a condensate pump is used, check with pump
manufacturer to verify pump is safe for use with antifreeze
used. Allow pump to start and pump anti--freeze to open
drain.
12. Replace main door.
13. When furnace is re--started, flush condensate pump with
clear water to check for proper operation before re--starting
furnace.
14. Propylene glycol need not be removed before re--starting
furnace.
A11392
Fig. 57 -- Priming Condensate Trap
(Appearance May Vary)
A11273
1-1/4-in.
(31.8)
2-1/2-in.
(64.4)
Fig. 58 -- Cleaning Heat Exchanger Cell
A11405
Fig. 55 -- Igniter Position -- Top View
Burner Flame
Burner
2−in.
50 mm
3/8−in.
9.6 mm
3/16−in.
4.6 mm
Manifold
+0.8
2.5 mm
−1.5
A11461
A11620
Fig. 59 -- Burner Flame
Fig. 56 -- Igniter Position -- Side View
79
59MN7A
Do not use ethylene glycol (automotive antifreeze coolant or
equivalent). Failure of plastic components may occur.
GROMMET
MOTOR SHAFT FLAT
MOTOR ARM
SCREW
SET SCREW
MOTOR WHEEL HUB
SEE DETAIL A
59MN7A
SCREW LOCATION
BLO HSG ASSY
BRACKET
BRACKET
ENGAGEMENT
DETAIL A
CUTOFF, BLOWER
WHEEL, BLOWER
BLOWER HSG ASSY
BRACKET
CAPACITOR
OR POWER CHOKE
(WHEN USED)
MOTOR, BLOWER
SCREW
(GND)
A11584
Fig. 60 -- Blower Assembly
80
IGNITER
BURNER SUPT. ASSY
BRACKET, IGNITER
59MN7A
BURNER ASSY
FLAME ROLLOUT
SWITCH
FLAME SENSOR
(BELOW BURNER)
A11403
Fig. 61 -- Burner Assembly
81
Fig. 62 -- Troubleshooting Guide
A11290A
82
Go to section below for the status code
that was flashed.
Determine status code. The status code
is a 2 digit number with the first digit
determined by the number of short
flashes and the second digit by the
number of long flashes?
YES
Is AMBER LED status light blinking
ON/OFF slowly with a combination of
short and long flashes?
NO
Is AMBER LED status light blinking
rapidly without a pause?
YES
Is AMBER LED status light on?
START
YES
NO
YES
NO
NO
NO
Was there a previous status code other
than #11?
NO
To recall previous status codes disconnect the R
thermostat connection, reset power, and put setup
switch SW1-1 in the ON position. The AMBER LED
will flash the status codes in the order of occurrence.
Record status codes until status code #11 flashes (1
short and 1 long flash). After status code #11
flashes the status codes will repeat. Status codes
are erased after 72 hours or can be manually erased
by putting setup switch SW1-1 in the ON position
and jumpering R, W/W1, and Y/Y2 simultaneously
until status code #11 is flashed. When done put
setup switch SW1-1 in the OFF position.
Check for correct line voltage polarity. If
units are twinned, check for proper lowvoltage (24V) transformer phasing.
Replace furnace control.
YES
Is there 24V at SEC-1 and SEC-2?
YES
Is there 115V at L1 and L2?
YES
Replace furnace control.
Run system through a minimum-heat,
maximum-heat, or cooling cycle to check
operation. Status codes are erased after
72 hours or can be manually erased by
putting setup switch SW1-1 in the ON
position and jumpering R, W/W1, and
Y/Y2 simultaneously until status code
#11 is flashed.
YES
Does the control respond to W/W1, W2,
Y1, Y/Y2, and G (24V) thermostat
signals?
Replace transformer.
Replace door switch.
YES
Is there 115V going to switch?
Is door switch closed?
Troubleshooting Guide
59MN7A
YES
NO
NO
NO
The thermostat is not compatible with the
furnace control. Either install a ballast
resistor, connect the Com24V thermostat
terminal to the thermostat, or replace the
thermostat.
NO
Does the problem repeat when using a
jumper wire?
Disconnect all the thermostat wires from
the furnace control.
YES
Is 24V present at W/W1, W2, Y1, Y/Y2 or
G thermostat terminals on the furnace
control?
NO
Check room thermostat or
interconnecting cable.
Close circuit breaker and go back to
START.
Check for continuity in wire from circuit
breaker to furnace.
YES
Is circuit breaker closed?
Close door switch.
NO
A11290B
83
24 SECONDARY VOLTAGE FUSE IS OPEN
Check for:
- Short circuit in secondary voltage (24V)
wiring including thermostat leads.
Disconnect thermostat leads to isolate
short circuit.
23 PRESSURE SWITCH DID NOT OPEN –
Check for:
- Obstructed pressure tube.
- Pressure switch stuck closed.
22 ABNORMAL FLAME-PROVING SIGNAL
Flame is proved while gas valve is deenergized. Inducer will run until fault is
cleared. Check for:
- Stuck open or leaky gas valve.
21 GAS HEATING LOCKOUT – Turn off
power and wait 5 minutes to retry. Check
for:
- Stuck closed gas valve relay on control.
- Miswire or short to gas valve BLUE wire.
15 BLOWER MOTOR LOCKOUT – Indicates
the blower failed to reach 250 RPM or the
blower failed to communicate within 30
seconds after being turned ON in two
successive heating cycles. Control will
auto-reset after 3 hours. See code 41.
14 IGNITION LOCKOUT – System failed to
ignite gas and prove flame in 4 attempts.
Control will auto-reset after 3 hours. See
status code 34.
13 LIMIT CIRCUIT LOCKOUT – Lockout
occurs if the limit or flame rollout switch is
open longer than 3 minutes or 10
successive limit trips occurred during
maximum-heat. Control will auto-reset
after 3 hours. See code 33.
12 BLOWER ON AFTER POWER UP –
(115V OR 24V) – Normal operation.
Blower runs for 90 seconds, if unit is
powered up during a call for heat (RW/W1 closed) or when (R-W/W1 opens)
during the blower on-delay period.
11 NO PREVIOUS CODE – Status codes are
erased after 72 hours or can be manually
erased by putting setup switch SW1-1 in
the ON position and jumpering R, W/W1,
and Y/Y2 simultaneously until status code
#11 is flashed. Run system through a
minimum-heat, maximum-heat, or cooling
cycle to check system.
34 IGNITION PROVING FAILURE – If flame is
not sensed during the trial for ignition
period, the control will repeat the ignition
sequence 3 more times before lockout #14
occurs. If flame signal is lost during the
blower on-delay period, blower will come on
for the selected blower off-delay. Check
the following items first before proceeding
to the next step.
- Gas valve turned off.
- Manual shut-off valve.
- GREEN/YELLOW wire MUST be
connected to furnace sheet metal.
- Flame sensor must not be grounded.
To determine whether the problem is in the
gas valve, igniter, or flame sensor the
system can be operated in component test
mode. To check the igniter remove the R
thermostat connection from the control,
reset power, and put setup switch SW1-6 in
the ON position to start the component test.
Does the igniter glow orange/white by the
end of the 15 second warm-up period?
33 LIMIT CIRCUIT FAULT – Indicates the
limit or a flame rollout switch is open or the
furnace is operating in maximum-heat only
mode due to 2 successive limit trips while
operating at any rate < 71% of maximum
rate. Blower will run for 4 min. or until
open switch remakes whichever is longer.
If open longer than 3 min., code changes
to lockout #13. If open less than 3 min.
status code #33 continues to flash until
blower shuts off. Flame rollout switch
requires manual reset. Check for:
- Loose blower wheel.
- Defective switch or connections.
- Improper minimum- or maximum-heat
gas input adjustment.
- Improper limit switch or no limit gasket.
- Dirty filter or restricted duct system.
32 LOW PRESSURE SWITCH DID NOT
CLOSE OR REOPENED – If opens during
blower on-delay period, blower will come
on for the selected blower off-delay. If
opens within 5 minutes after ignition the
next heating cycle will be restricted to
maximum-heat. Check for:
- Proper vent sizing.
- Air leak between vestibule and blower
compartment.
- Low inlet gas pressure (if LGPS used).
- Restricted vent.
- Disconnected or obstructed pressure
tubing.
- Defective or miswired pressure switches
- Excessive wind. If problem persists turn
setup switch SW1-3 ON to boost
inducer speed
- Plugged condensate drain.
- Water in vent piping, possible sagging
pipe.
YES
NO
Fixed.
59MN7A
YES
Will main burners ignite and stay on?
YES
Is current near typical value?
Clean flame sensor with fine steel wool
and recheck current. Nominal current is
4.0 to 6.0 microamps.
Repeat call for heat and check flame
sensor current during trial for ignition
period. Is the DC microamps below 0.5?
NO
Do the main burners stay on?
YES
Do the main burners ignite?
YES
Does gas valve open and allow gas to
flow?
YES
Reconnect the R thermostat lead and set
thermostat to call for heat. Connect
voltmeter across gas valve BLUE and
GREEN/YELLOW wires. Does gas valve
receive 24V?
Unplug igniter harness from control and
repeat component test by turning setup
switch SW1-6 OFF and then back ON.
Check for 115V between pin 3 and
NEUTRAL-L2 on the control. Was 115V
present for the 15 second period?
43 LOW OR MEDIUM PRESSURE SWITCH
OPEN WHILE MEDIUM OR HIGH
PRESSURE SWITCH IS CLOSED Check for:
- Low or Med press. switch stuck open.
- Disconnected or obstructed pressure
tubing.
- Improper pressure switch wiring.
- Low inlet gas pressure (if LGPS used).
- Plugged condensate drain.
- Water in vent piping, possible sagging
pipe.
NO
NO
NO
YES
NO
NO
NO
YES
NO
Replace furnace control.
Replace electrode.
Check connections and retry.
If current is near typical value
(4.0-6.0 nominal) and burners
will not stay on, repeat check
in max-heat. If burners will
still not stay on replace
control. If burners operate in
max-heat then switch to
intermediate-heat, check
manifold pressure. If OK,
check burner carryover and
flame sensor location.
Allow unit to drop to min-heat,
and check manifold pressure.
Repeat test to check for
intermittent operation.
Check for:
- Inadequate flame carryover
or rough ignition.
- Low inlet gas pressure.
- Proper firing rate.
Check that all gas valves are
turned on. Replace valve.
Check connections. If OK,
replace control.
Check for continuity in the
harness and igniter. Replace
defective component.
Replace furnace control.
45 CONTROL CIRCUITRY
LOCKOUT Auto-reset
after 1 hour lockout due
to:
- Flame circuit failure.
- Gas valve relay stuck
open.
- Software check error.
Reset power to clear
lockout. Replace control
if code repeats.
A11290C
84
42 INDUCER MOTOR FAULT – Indicates the
inducer motor has not started within 20
seconds after a call for heat, the inducer
motor RPM is outside its valid range of
operation, or the inducer RPM signal was
lost for 5 seconds during operation.
Check for:
- Proper vent sizing.
- Failed inducer motor.
- Restricted combustion air supply.
- Improper motor wiring.
35 GAS VALVE FAULT – Indicates the
modulating gas valve failed to respond to
a command from the furnace control or
power to the gas valve electronics was
interrupted. Check for:
- Intermittent RED, YELLOW, or
ORANGE wire at gas valve or PL8
connections.
31 MEDIUM PRESSURE SWITCH, HIGH
PRESSURE SWITCH, OR PSR RELAY
DID NOT CLOSE OR REOPENED Check for:
- PSR relay may be defective.
- See status code 32.
25 INVALID MODEL SELECTION OR
SETUP ERROR – If status code 25 only
flashes 4 times on power-up the control is
missing its model plug PL4 and is
defaulting to the model selection stored in
memory. If status code 25 flashes
continuously it could indicate any of the
following:
- Model plug PL4 is missing and there is
no valid model stored in permanent
memory. This will happen if you forget
to install the model plug PL4 on a
service replacement control.
- Thermostat call with SW1-1 ON.
- Thermostat call with SW1-6 ON.
- SW1-1 and SW1-6 both ON.
- Two different furnace models twinned.
- Service replacement control is incorrect.
Need modulating board with software
version V17 or later.
YES
Replace the blower control module attached to
the blower motor. Follow the instructions with
the blower control module to make sure the
entire blower motor does not need to be
replaced.
YES
Does the voltage fluctuate as described in the
previous step?
NO
Connect a DC voltmeter across PL3-4 BLUE
(+) and PL3-2 GREEN (-). Does the voltage
fluctuate as described two steps back?
NO
Replace the furnace control.
You have an open wire or bad terminal on the
BLUE wire between the furnace control and the
blower motor.
Replace the blower control module attached to
the blower motor. Follow the instructions with
the blower control module to make sure the
entire blower motor does not need to be
replaced.
NO
41 BLOWER MOTOR FAULT – Indicates the
blower failed to reach 250 RPM or the
blower failed to communicate within the
prescribed time limits. Thirty seconds
after being turned ON or ten seconds
during steady-state operation. Turn power
off and check the following items first
before proceeding to the next step.
- Rubbing blower wheel.
- Loose blower wheel.
- Wiring from furnace control to blower
motor.
Remove the R thermostat connection from
the furnace control, disconnect both
connectors from the blower motor PL13
and PL14. Does the blower wheel turn
freely?
YES
YES
YES
Turn power off, disconnect PL13 and
PL14 from the blower motor, then turn
power back on. Connect a DC voltmeter
across PL13-3 BLUE (+) and PL13-4
GREEN (-). The voltage should be near
0-VDC but it will fluctuate briefly several
times a second. If you have an analog
voltmeter the needle will briefly go high
several times a second. If you have a
digital voltmeter with a bar graph it will
show a large change in magnitude on the
bar graph several times a second. If you
have a standard digital voltmeter it will
show a brief fluctuation in voltage and the
magnitude may vary depending on the
voltmeter used.
NO
Turn power off, reconnect PL13 and
PL14 to the blower motor, then turn
power back on. Connect a DC voltmeter
across PL3-3 YELLOW (+) and PL3-2
GREEN (-). Does the voltage fluctuate
more than it did in the previous step?
The voltage just measured should be
very stable and should not fluctuate more
than .02-VDC. If the voltage fluctuates
more than this get a different voltmeter
before proceeding.
YES
Is there 5-VDC at PL13-2 YELLOW (+)
and PL13-4 GREEN (-)?
Replace the furnace control.
NO
Is there 12-VDC at PL3-1 RED (+) and
PL3-2 GREEN (-)?
NO
Is there 12-VDC at PL13-1 RED (+) and
PL13-4 GREEN (-)?
YES
Turn power back on. Is there 115VAC at
PL14-5 and PL14-4?
59MN7A
NO
YES
NO
You have an open wire or bad
terminal on the YELLOW wire
between the furnace control and
the blower motor.
YES
Is there 5-VDC at PL3-3
YELLOW (+) and PL3-2
GREEN (-)?
NO
You have an open wire or bad
terminal on either the RED or
GREEN wire between the
furnace control and the blower
motor.
You have an open wire or bad
terminal on either the BLACK or
WHITE power leads between
the furnace control and the
blower motor. If you have a
power choke disconnect it and
check continuity.
!
CAUTION
UNIT OPERATION HAZARD
Failure to follow this caution may result in intermittent unit
operation.
Furnace control must be grounded for proper operation or
control will lock out. Control is grounded through
green/yellow wire routed to gas valve and burner box
screw.
Using the schematic diagram (See Fig. 63), follow the sequence of
operation through the different modes. Read and follow the wiring
diagram very carefully!!
NOTE: If a power interruption occurs during a call for heat
(W/W1 or W/W1-and-W2), the control will start a 90-second
blower-only ON period two seconds after power is restored, if the
thermostat is still calling for gas heating. The amber LED light will
flash code 12 during the 90-second period, after which the LED
will be ON continuous, as long as no faults are detected. After the
90-second period, the furnace will respond to the thermostat
normally.
The blower door must be installed for power to be conducted
through the blower door interlock switch ILK to the furnace
control CPU, transformer TRAN, inducer motor IDM, blower
motor BLWM, hot surface igniter HSI, and gas valve GV.
Communicating Control and Modulating Heating
(Adaptive Mode)
Best comfort will be attained when a communicating wall control
is used with this product. Wiring and set--up instructions are
provided with the communicating control. See the furnace data
sheet accessory section for help in selecting the appropriate
communicating control for this furnace.
When a communicating control is used, the furnace will modulate
through its full operation range, or can be limited via the minimum
and maximum cfm configurations.
Operation of the furnace at the beginning and end of each heating
cycle will be the same as detailed below in the Single--Stage
Thermostat section EXCEPT that the communicating control will
send modulating rate command signals through the communication
bus rather than energizing the 24--v thermostat terminals. Note that
the R to W/W1 circuit signal will be controlled by the COMMR
relay on the furnace control. See the wiring diagram in Fig. 63 .
Single-Stage Thermostat and Modulating Heating
(Adaptive Mode)
See Fig. 34 and 35 for thermostat connections.
NOTE:
Minimum-heat only switch SW1-2 selects the
minimum-heat only operation mode when ON. Intermediate-heat
only switch SW4-2 selects intermediate-heat only operation
mode when ON. If both switches are ON the furnace control will
default to intermediate-heat. If either or both switches are ON, the
furnace control will operate at two-stages only as referenced in
Two Stage Thermostat section below. If both switches are OFF the
furnace control will operate in the adaptive heating mode in
response to a call for heat. (See Fig. 54.) When the W2 thermostat
terminal is energized it will always cause maximum-heat operation
as long as the R to W circuit is closed, regardless of the setting of
the minimum-heat or intermediate-heat only switches.
This furnace can operate as a modulating furnace with a
single-stage thermostat because the furnace control CPU includes a
programmed adaptive sequence of controlled operation, which
selects a modulated rate between minimum- and maximum-heat.
This selection is based upon the stored history of the length of
previous gas-heating periods of the single-stage thermostat.
The furnace will start up in either intermediate-, or maximum-heat.
The furnace will transition and operate at minimum-heat or the
calculated modulating rate after starting and operating for 45
seconds at intermediate-heat. The furnace control CPU defaults to
minimum-heat on the first thermostat cycle and calculates the
modulating rate that the furnace should run at for 19 minutes on
subsequent heat cycles.
If the power is interrupted, the stored modulating rate is erased and
the furnace control will select intermediate-heat for 45 seconds,
minimum-heat for 19 minutes and then switch to maximum-heat,
as long as the thermostat continues to call for heat. The furnace
control CPU then uses this information to calculate the modulating
rate the furnace will operate at on the next heating cycle. If the
calculated modulating rate is between 40% - 99% then the furnace
control CPU will operate for 45 seconds at intermediate-heat, and
then operate at the calculated modulating rate for up to 19 minutes
and then switch to maximum-heat as long as the thermostat
continues to call for heat. If the calculated modulating rate is 100%
then the furnace control will only operate at maximum-heat until
the thermostat is satisfied.
The wall thermostat ”calls for heat”, closing the R to W circuit. The
furnace control CPU performs a self-check, verifies the low,
medium, and high pressure switch contacts LPS,MPS, and HPS are
open, then de-energizes the PSR relay to close the NC contact.
1. Inducer Prepurge Period - The furnace control CPU turns
on inducer motor IDM and slowly increases the inducer
motor speed. After the low pressure switch LPS closes the
furnace control CPU continues to increase the inducer motor speed until the medium pressure switch MPS closes.
When the medium pressure switch MPS closes, inducer motor RPM is noted by the furnace control CPU, and a
25-second prepurge period begins. The RPM is used to
evaluate vent system resistance. This evaluation is then
used to determine the required RPM necessary to operate
the inducer motor during pre-purge, the first 45 seconds of
intermediate-heat, or any modulating rate that the furnace
will transition to after the blower on-delay is completed.
NOTE: The heat cycle can start in either intermediate- or
maximum-heat. If a maximum-heat cycle is initiated, the furnace
control CPU will continue to increase the inducer motor speed
after the medium pressure switch MPS closes. When the medium
pressure switch closes, inducer motor RPM is noted by the furnace
control CPU, and a 25-second prepurge period begins. The RPM
is used to evaluate vent system restriction. This evaluation is then
used to determine the required RPM necessary to operate the
inducer motor in maximum-heat pre-purge, or maximum-heat.
The high pressure switch HPS should be closed before ignition but
the furnace control ignores this input until after ignition occurs.
2. Igniter Warm-Up - At the end of the prepurge period, the
Hot-Surface Igniter HSI is energized for a 17-second igniter warm-up period
3. Trial-For-Ignition Sequence - When the igniter warm-up
period is completed the main gas valve relay contact GVR
closes to energize the gas valve solenoid GV (pin 5). The
gas valve solenoid GV (pin 5) permits gas flow to the burners where it is ignited. Five seconds after the GVR closes, a
2-second Flame-Proving period begins. The HSI igniter
will remain energized until flame is sensed or until the
2-second flame proving period begins.
4. Flame-Proving - When the burner flame is proved at the
flame-proving sensor electrode FSE, the furnace control
CPU begins the blower-ON delay period and continues to
hold the gas valve GV (pin 5) open. If the burner flame is
not proved within two seconds, the furnace control CPU
will close the gas valve GV (pin 5), and the furnace control
85
59MN7A
SEQUENCE OF OPERATION
59MN7A
CPU will repeat the ignition sequence for up to three more
Trials-For-Ignition before going to Ignition-Lockout. Lockout will be reset automatically after three hours, or by momentarily interrupting 115 vac power to the furnace, or by
interrupting 24 vac power at SEC1 or SEC2 to the furnace
control CPU (not at W/W1, G, R, etc.).
If flame is proved when flame should not be present, the
furnace control CPU will lock out of Gas-Heating mode and
operate the inducer motor IDM at full speed until flame is
no longer proved.
5. Inducer Speed Change - If the cycle starts in intermediate-heat, the furnace control CPU reduces the inducer speed
slightly after flame sense. If cycle starts in maximum-heat,
the furnace control CPU increases the inducer speed after
flame sense.
6. Blower-On delay — If the burner flame is proven, the
blower-ON delay for intermediate-heat and maximum-heat
are as follows:
Intermediate-heat - 45 seconds after the gas valve GV (pin
5) is opened the blower motor BLWM is turned ON at the
modulating heat airflow.
Maximum-heat - 25 seconds after the gas valve GV (pin 5)
is opened the BLWM is turned ON at maximum-heat airflow.
Simultaneously, the humidifier terminal HUM and electronic air cleaner terminal EAC-1 are energized and remain
energized throughout the heating cycle.
7. Switching from Intermediate-Heat to a Low Range Input - If the furnace control CPU switches from intermediate-heat to a low range input (low range input is an input
rate less than or equal to 51% of full rate), the furnace
control CPU will turn the blower ON or switch to the modulating heat airflow, energize the PSR relay to open the NC
contact, and slowly decrease the inducer motor speed to the
desired inducer RPM.
Switching from a Intermediate-Heat to a Medium
Range Input - If the furnace control CPU switches from
intermediate-heat to a different medium range input (medium range input is an input rate between 52% and 71% of
full rate), the furnace control CPU will turn the blower ON
or switch to the modulating heat airflow, and continue to
maintain the inducer motor speed or change it further if required.
Switching from a Intermediate-Heat to a High Range
Input - If the furnace control CPU switches from intermediate-heat to a high range input (high range input is an input
rate greater than or equal to 72% of full rate), the furnace
control CPU will turn the blower ON or switch to the modulating heat airflow, and increase the inducer motor speed to
the desired inducer motor RPM.
Switching from Low Range Input to Maximum-Heat - If
the furnace control CPU switches from a low range input
to maximum-heat, the furnace control CPU will de-energize the PSR relay to close the NC contact and slowly increase the inducer motor speed until the medium pressure
switch MPS closes. When the medium pressure switch
MPS closes the inducer motor RPM is noted by the furnace
control CPU. The RPM is used to evaluate vent system resistance. This evaluation is then used to determine the required RPM necessary to operate the inducer motor at
maximum-heat. The blower motor BLWM will transition
to maximum-heat airflow five seconds after the furnace
control CPU switches from a low range input to maximum-heat. As the inducer RPM increases, the high pressure
switch HPS should close.
Switching from Medium Range Input to Maximum-Heat - If the furnace control CPU switches from medium range input to maximum-heat, the furnace control CPU
will increase the inducer motor speed to the maximum-heat
inducer motor RPM. The blower motor BLWM will transition to the maximum-heat airflow five seconds after the
furnace control CPU switches from a medium range input
to maximum-heat. As the inducer RPM increases, the high
pressure switch HPS should close.
8. Blower-Off Delay — When the thermostat is satisfied, the
R to W circuit is opened, de-energizing the gas valve GV
(pin 5), stopping gas flow to the burners, and humidifier terminal HUM. The inducer motor IDM will remain energized
for a 15-second post-purge period. The blower motor BLWM and air cleaner terminal EAC-1 will remain energized
at minimum-heat airflow or transition to minimum-heat airflow for 90, 120, 150, or 180 seconds (depending on selection at blower-OFF delay switches). The furnace control
CPU is factory-set for a 120-second blower- OFF delay.
Two-- Stage Thermostat and Modulating Heating
(Adaptive Mode)
Operation of Modulating Heating (Adaptive Mode; SW1--2 and
SW4--2 are both OFF) with a two--stage thermostat is the same as
with a single--stage thermostat, EXCEPT for the following:
If the two--stage thermostat R--W2 circuit closes along with the R
to W/W1 circuit, while the furnace is operating at any capacity less
than maximum, the furnace will switch to the maximum heating
capacity. At this point, the furnace control heating algorithm is
overridden and the two--stage thermostat takes control of staging
until BOTH R to W/W1 and R to W2 circuits are opened.
The furnace with transition back to the lower heating capacity if
the two--stage thermostat opens the R--W2 circuit, but leaves R to
W/W1 circuit closed. The furnace control will continue to follow
the commands from the two--stage thermostat for W/W1 and W2,
until the R to W/W1 circuit is opened.
After the two--stage thermostat opens both the R to W/W1 and R to
W2 circuits, the adaptive algorithm will set the beginning capacity
of the next heating cycle to the same value as the heating cycle that
most recently completed.
Two-Stage Thermostat and Two-Stage Minimum/Maximum Heating
See Fig. 34 and 35 for thermostat connections.
NOTE: In this mode, the minimum-heat only switch SW1-2 must
be ON to select the minimum-heat only operation mode in
response to closing the thermostat R to W1 circuit. Closing the
thermostat R to W1-and-W2 circuits always causes
maximum-heat operation, regardless of the setting of the
minimum-heat only switch.
The furnace will start up in either intermediate-, or maximum-heat.
The furnace will operate in minimum-heat after starting and
operating for 1 minute at intermediate-heat before transitioning to
minimum-heat.
The wall thermostat ”calls for heat”, closing the R to W1 circuit for
minimum-heat or closing the R to W1-and-W2 circuits for
maximum-heat. The furnace control performs a self-check, and
verifies the low, medium and high pressure switch contacts LPS,
MPS and HPS are open, then de-energizes the PSR relay to close
the NC contact.
The start up and shut down functions and delays described above
apply to the 2-stage minimum/maximum heating mode as well,
except for switching from maximum- to minimum-heat.
1. Switching from Maximum- to Minimum-Heat — If the
thermostat R to W2 circuit opens, and the R to W1 circuit
remains closed, the furnace control CPU will gradually decrease the inducer motor speed to the required intermediate-heat RPM. When the inducer motor IDM reduces pressure sufficiently, the high pressure switch HPS will open
and the gas rate will be changed to intermediate-heat. The
gas valve solenoid GV (pin 5) will remain energized as long
as the low pressure switch LPS remains closed. When the
86
Two-Stage Thermostat and Two-Stage Intermediate/
Maximum Heating
See Fig. 34 and 35 for thermostat connections
NOTE: In this mode the intermediate-heat only switch SW4-2
must be ON to select the intermediate-heat only operation mode in
response to closing the thermostat R to W1 circuit. Closing the
thermostat R to W1-and-W2 circuits always causes
maximum-heat operation, regardless of the setting of the
intermediate-heat only switch.
The wall thermostat ”calls for heat”, closing the R to W1 circuit for
intermediate-heat or closing the R to W1-and-W2 circuits for
maximum-heat. The furnace control performs a self-check, and
verifies the low, medium and high pressure switch contacts LPS,
MPS and HPS are open , then de-energizes the PSR relay to close
the NC contact.
The start up and shut down functions and delays described above
apply to the 2-stage intermediate/maximum heating mode as well,
except for switching from maximum- to intermediate-heat.
1. Switching from Maximum- to Intermediate-Heat — If
the thermostat R to W2 circuit opens, and the R to W1 circuit remains closed, the furnace control CPU will gradually
decrease the inducer motor speed to the required intermediate-heat RPM. When the inducer motor IDM reduces
pressure sufficiently, the high pressure switch HPS will
open and the gas rate will be changed to intermediate-heat.
When the inducer motor speed gets within 15% of the required intermediate-heat RPM the furnace control CPU will
start a 5 second blower airflow change delay. After the 5
second blower airflow change delay is completed the
blower airflow will transition to intermediate-heat airflow.
Cooling Mode
The thermostat “calls for cooling.”
1. Single-Speed Cooling
See Fig. 34 and 35 for thermostat connections.
The thermostat closes the R to G-and-Y circuits. The R to Y circuit
starts the outdoor unit, and the R to G-and-Y/Y2 circuits start the
furnace blower motor BLWM on cooling airflow. Cooling airflow
is based on the A/C selection shown in Fig. 54.
The electronic air cleaner terminal EAC-1 is energized with 115
vac when the blower motor BLWM is operating. When the
thermostat is satisfied, the R to G-and-Y circuits are opened. The
outdoor unit will stop, and the furnace blower motor BLWM will
continue operating at cooling airflow for an additional 90 seconds.
Jumper Y/Y2 to DHUM to reduce the cooling off-delay to 5
seconds. (See Fig. 34.)
2. Single-Stage Thermostat and Two-Speed Cooling (Adaptive Mode)
See Fig. 34 and 35 for thermostat connections.
This furnace can operate a two-speed cooling unit with a
single-stage thermostat because the furnace control CPU includes a
programmed adaptive sequence of controlled operation, which
selects low-cooling or high-cooling operation. This selection is
based upon the stored history of the length of previous cooling
period of the single-stage thermostat.
NOTE: The air conditioning relay disable jumper ACRDJ must be
connected to enable the adaptive cooling mode in response to a call
for cooling. (See Fig. 34.) When in place the furnace control CPU
can turn on the air conditioning relay ACR to energize the Y/Y2
terminal and switch the outdoor unit to high-cooling.
The furnace control CPU can start up the cooling unit in either
low- or high-cooling. If starting up in low-cooling, the furnace
control CPU determines the low-cooling on-time (from 0 to 20
minutes) which is permitted before switching to high-cooling.
If the power is interrupted, the stored history is erased and the
furnace control CPU will select low-cooling for up to 20 minutes
and then energize the air conditioning relay ACR to energize the
Y/Y2 terminal and switch the outdoor unit to high-cooling, as long
as the thermostat continues to call for cooling. Subsequent
selection is based on stored history of the thermostat cycle times.
The wall thermostat “calls for cooling”, closing the R to G and- Y
circuits. The R to Y1 circuit starts the outdoor unit on low-cooling
speed, and the R to G-and-Y1 circuits starts the furnace blower
motor BLWM at low-cooling airflow which is the true on-board
CF selection as shown in Fig. 54.
If the furnace control CPU switches from low-cooling to high
cooling, the furnace control CPU will energize the air conditioning
relay ACR. When the air conditioning relay ACR is energized the
R to Y1-and-Y2 circuits switch the outdoor unit to high-cooling
speed, and the R to G-and-Y1- and-Y/Y2 circuits transition the
furnace blower motor BLWM to high-cooling airflow.
High-cooling airflow is based on the A/C selection shown in Fig.
54.
NOTE: When transitioning from low-cooling to high-cooling the
outdoor unit compressor will shut down for 1 minute while the
furnace blower motor BLWM transitions to run at high-cooling
airflow.
The electronic air cleaner terminal EAC-1 is energized with 115
vac whenever the blower motor BLWM is operating.
When the thermostat is satisfied, the R to G-and-Y circuit are
opened. The outdoor unit stops, and the furnace blower BLWM
and electronic air cleaner terminal EAC-1 will remain energized for
an additional 90 seconds. Jumper Y1 to DHUM to reduce the
cooling off-delay to 5 seconds. (See Fig. 34.)
3. Two Stage Thermostat and Two-Speed Cooling
See Fig. 34 and 35 for thermostat connections.
NOTE: The air conditioning relay disable jumper ACRDJ must
be disconnected to allow thermostat control of the outdoor unit
staging. (See Fig. 34.)
The thermostat closes the R to G-and-Y1 circuits for low cooling
or closes the R to G-and-Y1-and-Y2 circuits for high cooling. The
R to Y1 circuit starts the outdoor unit on low cooling speed, and
the R to G-and-Y1 circuit starts the furnace blower motor BLWM
at low-cooling airflow which is the true on-board CF selection as
shown in Fig. 54. The R to Y1-and-Y2 circuits start the outdoor
unit on high-cooling speed, and the R to G-and-Y/Y2 circuits start
the furnace blower motor BLWM at high-cooling airflow.
High-cooling airflow is based on the A/C selection shown in Fig.
54.
The electronic air cleaner terminal EAC-1 is energized with 115
vac whenever the blower motor BLWM is operating.
When the thermostat is satisfied, the R to G-and-Y1 or R to
G-and-Y1-and-Y2 circuits are opened. The outdoor unit stops, and
the furnace blower BLWM and electronic air cleaner terminal
EAC-1 will remain energized for an additional 90 seconds. Jumper
Y1 to DHUM to reduce the cooling off-delay to 5 seconds. (See
Fig. 54.)
4. Dehumidification Mode
See Fig. 34 and 35 for thermostat connections.
The dehumidification output, D or DHUM on the Thermostat
should be connected to the furnace control thermostat terminal
87
59MN7A
inducer motor speed gets within 15% of the required intermediate-heat RPM the furnace control CPU will start a 5
second blower airflow change delay. After the 5 second
blower airflow change delay is completed the blower airflow will transition to minimum-heat airflow. At this point
the furnace control CPU will energize the PSR relay to open
the NC contact and slowly decrease the inducer motor
speed to the required minimum-heat RPM. When the
PSR relay is energized and the NC contact opens the furnace control CPU will reduce the gas rate to minimum-heat
RPM.
59MN7A
DHUM. When there is a dehumidify demand, the DHUM input is
activated, which means 24 vac signal is removed from the DHUM
input terminal. In other words, the DHUM input logic is reversed.
The DHUM input is turned ON when no dehumidify demand
exists. Once 24 vac is detected by the furnace control,
dehumidification capability is activated. If the DHUM input is
removed for more than 48 hours, the furnace control reverts back
to non-dehumidification mode.
The cooling operation described above in the Cooling Mode
section also applies to Dehumidification mode. The exceptions are
listed below:
a. Low cooling – When the R to G-and-Y1 circuit is closed
and there is a demand for dehumidification, the furnace
blower motor BLWM will drop the blower airflow to 86%
of low cooling airflow which is the true on-board CF
selection as shown in Fig. 54.
b. High cooling – When the R to G-and Y/Y2 circuit is closed
and there is a demand for dehumidification, the furnace
blower motor BLWM will drop the blower airflow to 86%
of high-cooling airflow. High-cooling airflow is based on
the A/C selection shown in Fig. 54.
c. Cooling off-delay – When the “call for cooling” is
satisfied and there is a demand for dehumidification, the
cooling blower-off delay is decreased from 90 seconds
to 5 seconds.
Super Dehumidify Mode
Super-Dehumidify mode can only be entered if the furnace control
is in the Dehumidification mode and there is a demand for
dehumidification. The cooling operation described in Cooling
Mode section above also applies to Super Dehumidify Mode. The
exceptions are listed below:
1. Low cooling – When the R to Y1 circuit is closed, R to G
circuit is open, and there is a demand for dehumidification,
the furnace blower motor BLWM will drop the blower airflow to 65% of low-cooling airflow for a maximum of 10
minutes each cooling cycle or until the R to G circuit closes
or the demand for dehumidification is satisfied. Low-cooling airflow is the true on-board CF selection as shown in
Fig. 54.
2. High cooling – When the R to Y/Y2 circuit is closed, R to
G circuit is open, and there is a demand for dehumidification, the furnace blower motor BLWM will drop the blower
airflow to 65% of high-cooling airflow for a maximum of
10 minutes each cooling cycle or until the R to G circuit
closes or the demand for dehumidification is satisfied.
High-cooling airflow is based on the A/C selection shown
in Fig. 54.
3. Cooling off-delay – When the “call for cooling” is satisfied
and there is a demand for dehumidification, the cooling
blower-off delay is decreased from 90 seconds to 5
seconds.
Continuous Blower Mode
When the R to G circuit is closed by the thermostat, the blower
motor BLWM will operate at continuous blower airflow.
Continuous blower airflow selection is initially based on the CF
selection shown in Fig. 54. Factory default is shown in Fig. 54.
Terminal EAC-1 is energized as long as the blower motor BLWM
is energized.
During a call for heat, the furnace control CPU will transition the
blower motor BLWM to continuous blower airflow, minimum-heat
airflow, or the mid-range airflow, whichever is lowest. The blower
motor BLWM will remain ON until the main burners ignite then
shut OFF and remain OFF for the blower-ON delay (45 seconds in
intermediate heat, and 25 seconds in maximum-heat), allowing the
furnace heat exchangers to heat up more quickly, then restarts at
the end of the blower-ON delay period at modulating or
maximum-heat airflow respectively.
The blower motor BLWM will revert to continuous-blower
airflow after the heating cycle is completed. When the thermostat
satisfies, the furnace control CPU will drop the blower motor
BLWM to minimum-heat airflow during the selected blower-OFF
delay period before transitioning to continuous-blower airflow.
When the thermostat “calls for low-cooling”, the blower motor
BLWM will operate at low-cooling airflow. When the thermostat is
satisfied, the blower motor BLWM will operate an additional 90
seconds at low-cooling airflow before transitioning back to
continuous-blower airflow.
When the thermostat “calls for high-cooling”, the blower motor
BLWM will operate at high cooling airflow. When the thermostat
is satisfied, the blower motor BLWM will operate an additional 90
seconds at high-cooling airflow before transitioning back to
continuous-blower airflow.
When the R to G circuit is opened, the blower motor BLWM will
continue operating for an additional 5 seconds, if no other function
requires blower motor BLWM operation.
Continuous Blower Speed Selection from Thermostat
To select different continuous-blower airflows from the room
thermostat, momentarily turn off the FAN switch or push button on
the room thermostat for 1-3 seconds after the blower motor
BLWM is operating.
The furnace control CPU will shift the continuous-blower airflow
from the factory setting to the next highest CF selection airflow as
shown in Fig. 54. Momentarily turning off the FAN switch again at
the thermostat will shift the continuous-blower airflow up one
more increment. If you repeat this procedure enough you will
eventually shift the continuous blower airflow to the lowest CF
selection as shown in Fig. 54. The selection can be changed as
many times as desired and is stored in the memory to be
automatically used following a power interruption.
Heat Pump
See Fig. 34 and 35 for thermostat connections. When installed with
a heat pump, the furnace control automatically changes the timing
sequence to avoid long blower off times during demand defrost
cycles. Whenever W/W1 is energized along with Y1 or Y/Y2, the
furnace control CPU will transition to or bring on the blower motor
BLWM at cooling airflow, minimum-heat airflow, or the mid-range
airflow, whichever is lowest. The blower motor BLWM will
remain on until the main burners ignite then shut OFF and remain
OFF for 25 seconds before coming back on at modulating heat
airflow. When the W/W1 input signal disappears, the furnace
control begins a normal inducer post-purge period while changing
the blower airflow. If Y/Y2 input is still energized the furnace
control CPU will transition the blower motor BLWM airflow to
cooling airflow. If Y/Y2 input signal disappears and the Y1 input is
still energized the furnace control CPU will transition the blower
motor BLWM to low-cooling airflow. If both the Y1 and Y/Y2
signals disappear at the same time, the blower motor BLWM will
remain on at minimum-heat airflow for the selected blower-OFF
delay period. At the end of the blower-OFF delay, the blower
motor BLWM will shut OFF unless G is still energized, in which
case the blower motor BLWM will operate at continuous blower
airflow.
Component Self Test
Refer to page 74 for instructions.
88
59MN7A
338307-201 Rev. F
A11595
Fig. 63 -- Wiring Diagram
89
PARTS REPLACEMENT INFORMATION GUIDE
Casing Group
Gas Control Group
Blower door
Bottom plate
Control door
Door knob assembly
Top filler plate
Burner
Flame sensor
Gas valve
Hot surface igniter
Manifold
Orifice
59MN7A
Electrical Group
3--Amp fuse
Circuit board
Control box
Door switch
Junction box
Limit switch(es)
Transformer
Heat Exchanger Group
Blower Group
Inducer Group
Blower housing
Blower motor
Blower wheel
Capacitor (when used)
Capacitor strap (when used)
Cut--off plate
Power choke (where used)
Collector box
Condensate trap
Condensate trap elbow
Gaskets
Inducer
Inducer assembly
Inducer motor capacitor (when used)
Inducer motor module (when used)
Pressure switch(es)
Containment plate
Coupling Box
Heat exchanger assembly
Primary HX cell panel
Secondary HX assembly
Tubing gaskets
Filter Group
Filter(s)
Media Cabinet (when used)
TO OBTAIN INFORMATION ON PARTS: Consult your installing dealer or classified section of your local telephone directory under
“Heating Equipment” or “Air Conditioning Contractors and Systems” headings for dealer listing by brand name or contact:
CARRIER CORPORATION
Consumer Relations Department
P.O. Box 4808
Syracuse, New York 13221
1--800--CARRIER
Have available the model number, series number, and serial number located on the unit rating plate to ensure correct replacement part.
Model Nomenclature
MODEL
HEATING
SIZE
MOTOR
WIDTH
VOLTAGE
MINOR SERIES
59MN7A
120
V
24
----
----
!
COOLING
AIRFLOW
(CFM)
22
WARNING
FIRE, EXPLOSION, ELECTRICAL SHOCK AND CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in dangerous operation, personal injury, death or property damage.
Improper installation, adjustment, alteration, service, or maintenance can cause personal injury, property damage, or death. Consult a
qualified installer, service agency, or your local gas supplier for information or assistance. The qualified installer or service agency
must use only factory--authorized replacement parts, kits, or accessories when modifying this product.
Copyright 2011 Carrier Corp. D 7310 W. Morris St. D Indianapolis, IN 46231
Printed in U.S.A.
Edition Date: 12/11
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
90
Catalog No:59MN7A ---04SI
Replaces: 59MN7A--- 03SI
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