Inst Manual P4DN 032-104 output

INSTALLATION MANUAL
HIGH EFFICIENCY
TUBULAR HEAT EXCHANGER SERIES
EFFICIENCY
RATING
CERTIFIED
MODELS: P*DN / G8T-DN / L8T-DN
(Single Stage Downflow / LoNOx)
This product was manufactured
in a plant whose quality system
is certified/registered as being
in conformity with ISO 9001.
40 - 130 MBH INPUT
(11.72 - 38.10 KW) INPUT
TABLE OF CONTENTS
SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
DUCTWORK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
GAS PIPING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
ELECTRICAL POWER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
TWINNING AND STAGING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
VENT SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
SAFETY CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
START-UP AND ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . . .18
WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
LIST OF FIGURES
Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Downflow Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Return Filter Grill and Return Duct Installation . . . . . . . . . . . . . . . . . . . 7
Gas Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Electrical Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Line Wiring Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Heating and Cooling Thermostat Connections . . . . . . . . . . . . . . . . . 10
Accessory Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Typical Twinned Furnace Application . . . . . . . . . . . . . . . . . . . . . . . . 10
Single Stage Twinning Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . 11
Two-Stage Twinning Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . 11
Vent Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Vent Termination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Typical Sidewall Vent Application . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Typical Sidewall Vent and Termination Configuration . . . . . . . . . . . .13
Home Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Combustion Airflow Path Through The Furnace Casing to the Burner
Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Atlernate Air Intake, Air Outlet and Chimney Connections . . . . . . . . .15
Air Inlet, Outlet and Chimney Connections . . . . . . . . . . . . . . . . . . . . .15
Typical Chimney Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Horizontal Air Inlet, Outlet and Chimney Connections . . . . . . . . . . . .16
Outside and Ambient Combustion Air . . . . . . . . . . . . . . . . . . . . . . . . .16
Pressure Switch Tubing Routing . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Gas Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Reading Gas Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Typical Heat/Cool Speed Tap Connections . . . . . . . . . . . . . . . . . . . .21
Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
LIST OF TABLES
Unit Clearances to Combustibles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Minimum Duct Sizing For Proper Airflow . . . . . . . . . . . . . . . . . . . . . . . 4
Round Duct Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Cabinet and Duct Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Filter Sizes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Inlet Gas Pressure Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
High Altitude Conversion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Ratings & Physical / Electrical Data - Upflow Models . . . . . . . . . . . . . 9
Roof Pitch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Horizontal Sidewall Venting Clearances . . . . . . . . . . . . . . . . . . . . . . .13
Estimated Free Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Free Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Unconfined Space Minimum Area in Square Inch . . . . . . . . . . . . . . .16
Inlet Gas Pressure Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Nominal Manifold Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Filter Performance - Pressure Drop Inches W.C. and (kPa) . . . . . . . .21
Blower Performance CFM - Upflow (without filter) . . . . . . . . . . . . . . .22
Field Installed Accessories - Non Electrical . . . . . . . . . . . . . . . . . . . .22
SECTION I: SAFETY
This is a safety alert symbol. When you see this symbol on
labels or in manuals, be alert to the potential for personal
injury.
Understand and pay particular attention to the signal words DANGER,
WARNING, or CAUTION.
DANGER indicates an imminently hazardous situation, which, if not
avoided, will result in death or serious injury.
WARNING indicates a potentially hazardous situation, which, if not
avoided, could result in death or serious injury.
CAUTION indicates a potentially hazardous situation, which, if not
avoided may result in minor or moderate injury. It is also used to
alert against unsafe practices and hazards involving only property damage.
Improper installation may create a condition where the operation of
the product could cause personal injury or property damage.
Improper installation, adjustment, alteration, service or maintenance can cause injury or property damage. Refer to this manual
for assistance or for additional information, consult a qualified contractor, installer or service agency.
This product must be installed in strict compliance with the installation instructions and any applicable local, state, and national codes
including, but not limited to building, electrical, and mechanical
codes.
035-19921-001 Rev. A (0404)
035-19921-001 Rev. A (0404)
SPECIFIC SAFETY RULES AND PRECAUTIONS
1.
Only Natural gas or Propane (LP) gas are approved for use with
this furnace. Refer to the furnace rating plate or Section IV of
these instructions.
2.
Install this furnace only in a location and position as specified in
SECTION I of these instructions.
3.
A gas-fired furnace for installation in a residential garage must be
installed as specified in SECTION I of these instructions.
4.
Provide adequate combustion and ventilation air to the furnace
space as specified in SECTION VII of these instructions.
5.
Combustion products must be discharged outdoors. Connect this
furnace to an approved vent system only, as specified in SECTION VII of these instructions.
•
•
•
•
•
•
FIRE OR EXPLOSION HAZARD
Failure to follow the safety warnings exactly could result in serious
injury, death or property damage.
Never test for gas leaks with an open flame. Use a commercially
available soap solution made specifically for detection of leaks to
check all connections. A fire or explosion may result causing property damage, personal injury or loss of life.
6.
Test for gas leaks as specified in SECTION XI of these instructions.
7.
Always install the furnace to operate within the furnace’s intended
temperature rise range. Only connect the furnace to a duct system
which has an external static pressure within the allowable range,
as specified on the furnace rating plate.
8.
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.
9.
The furnace is not to be used for temporary heating of buildings or
structures under construction.
10. When installed in a Non-HUD-Approved Modular Home or building
constructed on-site, combustion air shall not be supplied from
occupied spaces.
11. The size of the unit should be based on an acceptable heat loss
calculation for the structure. ACCA, Manual J or other approved
methods may be used.
SAFETY REQUIREMENTS
•
•
•
•
2
This furnace should be installed in accordance with all national
and local building/safety codes and requirements, local plumbing
or wastewater codes, and other applicable codes. In the absence
of local codes, install in accordance with the National Fuel Gas
Code ANSI Z223.1/NFPA 54, National Fuel Gas Code, and/or
CAN/CGA B149.1 Natural Gas and Propane Installation Code
(latest editions). Furnaces have been certified to the latest edition
of standard ANSI Z21-47 • CSA 2.3.
Refer to the unit rating plate for the furnace model number, and
then see the dimensions page of this instruction for return air plenum dimensions in Figure 1. The plenum must be installed
according to the instructions.
Provide clearances from combustible materials as listed under
Clearances to Combustibles.
Provide clearances for servicing ensuring that service access is
allowed for both the burners and blower.
•
•
These models ARE NOT CSA listed or approved for installation
into a HUD Approved Modular Home or a Manufactured
(Mobile) Home.
This furnace is not approved for installation in trailers or recreational vehicles.
Failure to carefully read and follow all instructions in this
manual can result in furnace malfunction, death, personal
injury and/or property damage.
Furnaces for installation on combustible flooring shall not be
installed directly on carpeting, tile or other combustible material
other than wood flooring.
Check the rating plate and power supply to be sure that the electrical characteristics match. All models use nominal 115 VAC, 1
Phase, 60-Hertz power supply. DO NOT CONNECT THIS APPLIANCE TO A 50 HZ POWER SUPPLY OR A VOLTAGE ABOVE
130 VOLTS.
Furnace shall be installed so the electrical components are protected from water.
Installing and servicing heating equipment can be hazardous due
to the electrical components and the gas fired components. Only
trained and qualified personnel should install, repair, or service
gas heating equipment. Untrained service personnel can perform
basic maintenance functions such as cleaning and replacing the
air filters. When working on heating equipment, observe precautions in the manuals and on the labels attached to the unit 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 who have not kept up with changing residential
and non-HUD modular home construction practices. These
instructions are required as a minimum for a safe installation.
COMBUSTION AIR QUALITY
(LIST OF CONTAMINANTS)
The furnace will require OUTDOOR AIR for combustion when the furnace is located in any of the following environments.
• Restricted Environments
• Commercial buildings
• Buildings with indoor pools
• Furnaces installed in laundry rooms
• Furnaces installed in hobby or craft rooms
• Furnaces installed near chemical storage areas
• Chemical Exposure
The furnace will require OUTDOOR AIR for combustion when the furnace is located in an area where the furnace is being exposed to the following substances and / or chemicals.
• Permanent wave solutions
• Chlorinated waxes and cleaners
• Chlorine based swimming pool chemicals
• Water softening chemicals
• De-icing salts or chemicals
• Carbon tetrachloride
• Halogen type refrigerants
• Cleaning solvents (such as perchloroethylene)
• Printing inks, paint removers, varnishes, etc.
• Hydrochloric acid
• Cements and glues
• Antistatic fabric softeners for clothes dryers
• Masonry acid washing materials
When outdoor air is used for combustion, the combustion air intake duct
system termination must be located external to the building and in an
area where there will be no exposure to the substances listed above.
Unitary Products Group
035-19921-001 Rev. A (0404)
at any point in the flue pipe between the furnace and the chimney
or a B-Vent. The flue products will condense in the vent pipe if the
flue temperature falls below 260° F (127° C) causing the vent pipe
to deteriorate rapidly.
The furnace area must not be used as a broom closet or for any
other storage purposes, as a fire hazard may be created. Never
store items such as the following on, near or in contact with the furnace.
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 items or containers; gasoline, kerosene, cigarette lighter fluid, dry cleaning fluids or other volatile fluid.
3. Paint thinners and other painting compounds.
4. Paper bags, boxes or other paper products
Never operate the furnace with the blower door removed. To
do so could result in serious personal injury and/or equipment
damage.
2.
Improper installation in an ambient below 32ºF (0.0° C) could create
a hazard, resulting in damage, injury or death.
3.
INSPECTION
As soon as a unit is received, it should be inspected for possible damage during transit. If damage is evident, the extent of the damage
should be noted on the carrier’s freight bill. A separate request for
inspection by the carrier’s agent should be made in writing. Also, before
installation the unit should be checked for screws or bolts, which may
have loosened in transit. There are no shipping or spacer brackets
which need to be removed.
FURNACE LOCATION AND CLEARANCES
The furnace shall be located using the following guidelines:
1.
2.
3.
4.
5.
6.
Do not allow return air temperature to be below 55º F (13° C) for
extended periods. To do so may cause condensation to occur in
the main heat exchanger, leading to premature heat exchanger
failure.
Where a minimum amount of air intake/vent piping and elbows will
be required.
As centralized with the air distribution as possible.
Where adequate combustion air will be available (particularly
when the appliance is not using outdoor combustion air).
Where it will not interfere with proper air circulation in the confined
space.
Where the outdoor vent terminal will not be blocked or restricted.
Refer to “VENT CLEARANCES” located in SECTION VII of these
instructions. These minimum clearances must be maintained in
the installation.
Where the unit will be installed in a level position with no more
than 1/4” (0.64 cm) slope side-to-side and front-to-back to provide
proper condensate drainage.
If this furnace is installed in an unconditioned space and an
extended power failure occurs, there will be potential damage to
the internal components. Following a power failure situation, do
not operate the unit until inspection and repairs are performed.
Clearances for access:
Ample clearances should be provided to permit easy access to the unit.
The following minimum clearances are recommended:
1.
Twenty-four (24) inches (61 cm) between the front of the furnace
and an adjacent wall or another appliance, when access is
required for servicing and cleaning.
2.
Eighteen (18) inches (46 cm) at the side where access is required
for passage to the front when servicing or for inspection or
replacement of flue/vent connections.
In all cases, accessibility clearances shall take precedence over clearances for combustible materials where accessibility clearances are
greater.
Downflow furnaces for installation on combustible flooring only
when installed on the accessory combustible floor base on wood
flooring only and shall not be installed directly on carpeting, tile or
other combustible material.
Check the rating plate and power supply to be sure that the electrical characteristics match. All models use nominal 115 VAC, 1
Phase 60Hz power supply.
Furnace shall be installed so the electrical components are protected from water.
Installation in freezing temperatures:
Installation in a residential garage:
1.
1.
Furnace shall be installed in an area where ventilation facilities
provide for safe limits of ambient temperature under normal operating conditions. Ambient temperatures may fall below 32° F (0° C)
providing the flue temperature does not fall below 260° F (127° C)
A gas-fired furnace for installation in a residential garage must be
installed so the burner(s) and the ignition source are located not
less than 18 inches (46 cm) above the floor, and the furnace must
be located or protected to avoid physical damage by vehicles.
TABLE 1: Unit Clearances to Combustibles
APPLICATION
TOP
FRONT
REAR
In. (cm) In. (cm) In. (cm)
LEFT SIDE RIGHT SIDE
FLUE
In. (cm)
In. (cm)
In. (cm)
FLOOR/
BOTTOM
CLOSET ALCOVE ATTIC
LINE
CONTACT
DOWNFLOW
1 (25.4)
6 (15.24)
0 (0.0)
0 (0.0)
3 (7.62)*
6 (15.24)
1 (25.4)1
YES
YES
YES
NO
DOWNFLOW B-VENT
1 (25.4)
3 (7.62)
0 (0.0)
0 (0.0)
0 (0.0)
1 (25.4)
1 (25.4)1
YES
YES
YES
NO
1. Special floor base or air conditioning coil required for use on combustible floor.
SECTION II: DUCTWORK
3.
Create a closed duct system. For residential and Non-HUD Modular Home installations, 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 a duct(s) sealed to the furnace casing and terminating outside
the space containing the furnace.
4.
Complete a path for heated or cooled air to circulate through the
air conditioning and heating equipment and to and from the conditioned space.
DUCTWORK GENERAL INFORMATION
The duct system’s design and installation must:
1.
Handle an air volume appropriate for the served space and within
the operating parameters of the furnace specifications.
2.
Be installed in accordance with standards of NFPA (National Fire
Protection Association) as outlined in NFPA pamphlets 90A and
90B (latest editions) or applicable national, provincial, or state, and
local fire and safety codes.
Unitary Products Group
3
035-19921-001 Rev. A (0404)
The cooling coil must be installed in the supply air duct, downstream of the furnace. Cooled air may not be passed over the heat
exchanger.
When the furnace is used in conjunction with a cooling coil, the coil
must be installed parallel with, or in the supply air side of the furnace to
avoid condensation in the primary heat exchanger. When a parallel flow
arrangement is used, dampers or other means used to control airflow
must be adequate to prevent chilled air from entering the furnace. If
manually operated, the damper must be equipped with means to prevent the furnace or the air conditioner from operating unless the damper
is in full heat or cool position.
1.
Take 8 x 14, which equals 112 sq.in. X 2, which equals 224 square
inch then go to round duct size located in Table 3.
2.
The square inch area for 7 inch round pipe is 38.4, multiply by 2 for
two round ducts which equals 76.8 square inch,
3.
Then take the 224 square inch from the rectangular duct and add it
to the 76.8 sq.in. of round duct. The total square inch of duct
attached to the furnace plenum is 300.8 square inch. This exceeds
the recommended 280 square inch of duct.
In this example, the duct system attached to the plenum has a sufficient
area so that the furnace operates at the specified external static pressure and within the air temperature rise specified on the nameplate.
TABLE 2: Minimum Duct Sizing For Proper Airflow
Input Airflow Return1 Rectangular2 Round2 Supply3 Rectangular2 Round2
FLOOR BASE AND DUCTWORK INSTALLATION
BTU/H
(kW)
40000
(11.72)
60000
(17.58)
80000
(23.44)
80000
(23.44)
100000
(29.31)
120000
(35.17)
Downflow Combustible Floor Base
NOTE: This chart does not replace proper duct sizing calcualtions or take into account static pressure drop for run length and fittings. Watch out for the temperature rise and static pressures.
The duct system must be properly sized to obtain the correct airflow
for the furnace size that is being installed.
Refer to Table 8 and the furnace rating plate for the correct rise
range and static pressures
If the ducts are undersized, the result will be high duct static pressures and/or high temperature rises which can result in a heat
exchanger OVERHEATING CONDITION. This condition can result
in premature heat exchanger failure, which can result in personal
injury, property damage, or death.
Installations on combustible material or floors must use a
combustible floor base shown in Figure 1. The perforations
in the wrapper flanges must be bent in towards the heat
exchanger to allow for the coil duct flange to recess into the
furnace Follow the instructions supplied with the combustible floor base accessory. This combustible floor base can
be replaced with a matching cooling coil, properly sealed to
prevent leaks. Follow the instructions supplied with the
cooling coil cabinet for installing the cabinet to the duct connector. Refer to the installation instructions for additional
information.
When replacing an existing furnace, if the existing plenum is not the
same size as the new furnace then the existing plenum must be
removed and a new plenum installed that is the proper size for the new
furnace.
The duct system is a very important part of the installation. If the duct
system is improperly sized the furnace will not operate properly.
The ducts attached to the furnace plenum, should be of sufficient size
so that the furnace operates at the specified external static pressure
and within the air temperature rise specified on the nameplate.
Table 2 is a guide for determining whether the rectangular duct system
that the furnace is being connected to be of sufficient size for proper furnace operation.
Use the Example below to help you in calculating the duct area to determine whether the ducts have sufficient area so that the furnace operates at the specified external static pressure and within the air
temperature rise specified on the nameplate.
Example: The furnace input is 80,000 BTUH, 1,200 CFM. The recommended duct area is 280 sq.in, there are two 8 x 14 rectangular ducts
attached to the plenum and there are two 7 inch round ducts attached to
the furnace.
4
In²
(cm²)
180
(457)
216
(549)
216
(549)
280
(711)
390
(991)
390
(991)
in. x in.
in. (cm)
(cm x cm)
dia.
10 x 18
16
(25.4 x 45.7) (40.6)
12 x 18
16
(30.5 x 45.7) (40.6)
12 x 18
16
(30.5 x 45.7) (40.6)
14 x 20
18
(35.6 x 50.8) (45.7)
16 x 22
22 (
(40.6 x 55.8) 55.8)
16 x 22
22
(40.6 x 55.8) (55.8)
1. Maximum return air velocity in rigid duct @ 700 feet per minute (19.82 m3 / minute).
2. Example return main trunk duct minimum dimensions.
3. Maximum supply air velocity in rigid duct @ 900 feet per minute (25.49 m3 / minute).
TABLE 3: Round Duct Size
Round Duct Size
inches (cm)
5 (13)
6 (15)
7 (18)
8 (20)
9 (23)
10 (25)
11 (28)
12 (30)
13 (33)
14 (36)
Downflow Duct Connectors
All downflow installations must use a suitable duct connector approved
by the furnace manufacturer for use with this furnace. The duct connectors are designed to be connected to the rectangular duct under the
floor and sealed. Refer to the instructions supplied with the duct connector for proper installation. Refer to the separate accessory parts list
at the end of these instructions for the approved accessory duct connectors.
CFM
In²
in. x in.
in. (cm)
(m³)
(cm²)
(cm x cm)
dia.
1,000
240
12 x 20
18
(28.32) (610) (30.5 x 50.8) 45.7)
1,200
280
14 x 20
18
(33.98) (711) (35.6 x 50.8) (45.7)
1,200
280
14 x 20
18
(33.98) (711) (35.6 x 50.8) (45.7)
1,600
360
18 x 20
22
(45.31) (914) (45.7 x 50.8) (55.8)
2,000
440
20 x 22
24
(56.63) (1,118) (50.8 x 55.8) (60.9)
2,000
440
20 x 22
24
(56.63) (1,118) (50.8 x 55.8) (60.9)
Calculated Area For Each Round Duct Size
Sq.in (cm2)
19.6 (126)
28.2 (182)
38.4 (248)
50.2 (324)
63.6 (410)
78.5 (506)
95 (613)
113.1 (730)
132.7 (856)
153.9 (993)
1.
The Air Temperature Rise is determined by subtracting the Return
Air Temperature Reading from the Supply Air Temperature Reading.
2. The External Static Pressure is determined by adding the Supply
Duct Static Pressure reading to the Return Duct Static Pressure
reading and adding the pressure drop across any applied a-coil
and return air filter.
TABLES 2 AND 3 are to be used as a guide only to help the installer
determine if the duct sizes are large enough to obtain the proper air flow
(CFM) through the furnace. TABLES 2 and 3 ARE NOT to be used to
design ductwork for the building where the furnace is being installed.
There are several variables associated with proper duct sizing that are
not included in the tables. To properly design the ductwork for the building, Refer to the ASHRAE Fundamentals Handbook, Chapter on
“DUCT DESIGN” or a company that specializes in Residential and Modular Home duct designs.
IMPORTANT: If the supply air duct is being connected to the furnace
without the use of an accessory duct connector, then a transition duct
must be installed with flanges or tabs that are securely attached and
sealed to the supply air duct and to the base of the furnace. The transition duct must have insulation between the transition duct and any combustible material.
The transition duct must be the same dimensional size as the rectangular opening in the base of the furnace.
Unitary Products Group
035-19921-001 Rev. A (0404)
Downflow Air Conditioning Coil Cabinet
The furnace should be installed with coil cabinet part number specifically intended for downflow application. If a matching cooling coil is
used, it may be placed directly on the furnace outlet and sealed to prevent leakage. For details of the coil cabinet dimensions and installation
requirements, refer to the installation instructions supplied with the coil
cabinet.
DOWNFLOW
FURNACE
WARM AIR PLENUM
WITH 1” FLANGES
FIBERGLASS
INSULATION
The perforations in the wrapper flanges must be bent away from the
heat exchanger to create duct flanges so the air conditioning coil can be
properly seated on the furnace. Attach the air conditioning coil cabinet
to the duct connector, and then position the furnace on top of the coil
cabinet. The connection to the furnace, air conditioning coil cabinet,
duct connector, and supply air duct must be sealed to prevent air leakage.
FIBERGLASS TAPE
UNDER FLANGE
COMBUSTIBLE FLOOR
BASE ACCESSORY
IMPORTANT: On all installations without a coil, a removable access
panel is recommended in the outlet duct such that smoke or reflected
light would be observable inside the casing to indicate the presence of
leaks in the heat exchanger. This access cover shall be attached in
such a manner as to prevent leaks.
FIGURE 1 : Combustible Floor Base Accessory
The supply air temperature MUST NEVER exceed the Maximum
Supply Air Temperature, specified on the nameplate.
Operating the furnace above the maximum supply air temperature
will cause the heat exchanger to overheat, causing premature heat
exchanger failure. Improper duct sizing, dirty air filters, incorrect
manifold pressure, incorrect gas orifice and/or a faulty limit switch
can cause the furnace to operate above the maximum supply air
temperature. Refer to sections II, III and XI for additional information on correcting the problem.
D
B
3/4
20
(Vent Connection)
T'STAT WIRING
7/8" K.O.
B
20
A
Power
Wiring
7/8" K.O.
20
Vent Connection
(vent size)
C
40
D
31-1/8
E
ALT. GAS INLET
1-1/4" X 2-1/2"
7-3/8
1-1/8
5
FRONT
FRONT
BOTTOM IMAGE
TOP IMAGE
5-3/4
2-1/2
A
F
1-7/8
GAS INLET
1-1/4" X 2-1/2"
1-1/8
28-1/2
FRONT
LEFT SIDE
RIGHT SIDE
FIGURE 2: Dimensions
TABLE 4: Cabinet and Duct Dimensions
Cabinet Dimension
BTUH (kW)
Input/Output
CFM (m3/min)
Cabinet
Size
A
A (cm)
B
B (cm)
C
C (cm)
D
D (cm)
F
F (cm)
E
40/32 (11.71/9.38)
1200 (33.98)
A
14 1/2
36.8
13 1/4
33.6
10 1/8
25.7
4.0
10.2
10 1/8
25.7
3 3/4
9.5
60/48 (17.6/14.07)
1200 (33.98)
A
14 1/2
36.8
13 1/4
33.6
10 1/8
25.7
4.0
10.2
10 1/8
25.7
3 3/4
9.5
80/64 (23.42/18.76)
1200 (33.98)
A
14 1/2
36.8
13 1/4
33.6
10 1/8
25.7
4.0
10.2
10 1/8
25.7
3 3/4
9.5
80/64 (23.42/18.76)
1600 (45.31)
B
17 1/2
44.4
16 1/4
41.3
13 1/8
33.3
4.0
10.2
11 5/8
29.5
3 3/4
9.5
E (cm)
80/64 (23.42/18.76)
2200 (62.30)
C
21
53.3
19 3/4
50.2
16 5/8
42.2
4.0
10.2
13 3/8
34
3 3/4
9.5
100/80 (29.28/23.42)
1200 (33.98)
B
17 1/2
44.4
16 1/4
41.3
13 1/8
33.3
4.0
10.2
11 5/8
29.5
3 3/4
9.5
100/80 (29.28/23.42)
1600 (45.31)
B
17 1/2
44.4
16 1/4
41.3
13 1/8
33.3
4.0
10.2
11 5/8
29.5
3 3/4
9.5
100/80 (29.28/23.42)
2000 (56.63)
C
21
53.3
19 3/4
50.2
16 5/8
42.2
4.0
10.2
13 3/8
34
3 3/4
9.5
115/92 (33.70/26.96)
1600 (45.31)
C
21
53.3
19 3/4
50.2
16 5/8
42.2
4.0
10.2
13 3/8
34
3 3/4
9.5
115/92 (33.70/26.96)
2000 (56.63)
C
21
53.3
19 3/4
50.2
16 5/8
42.2
4.0
10.2
13 3/8
34
3 3/4
9.5
130/104 (38.09/30.48)
2000 (56.63)
D
24 1/2
62.2
23 1/4
59.1
20 1/8
51.1
4.0
10.2
15 1/8
27.6
3 3/4
9.5
Unitary Products Group
5
035-19921-001 Rev. A (0404)
RESIDENTIAL AND NON HUD MODULAR HOME
DOWNFLOW RETURN PLENUM CONNECTION
The duct system is a very important part of the installation. If the duct
system is improperly sized the furnace will not operate properly. The
ducts attached to the furnace must be of sufficient size so that the furnace operates at the specified external static pressure and within the air
temperature rise specified on the nameplate.
The return duct system must be connected to the furnace inlet and the
return duct system must terminate outside the space containing the furnace. When replacing an existing furnace, if the existing plenum is not
the same size as the new furnace then the existing plenum must be
removed and a new plenum installed that is the proper size for the new
furnace.
IMPORTANT: If an external mounted filter rack is being used see the
instructions provided with that accessory for proper hole cut size.
SECTION III: FILTERS
Attach the return plenum to the furnace inlet duct flanges. This is typically through the use of “S” cleat material when a metal plenum is used.
The use of an approved flexible duct connector is recommended on all
installations. The connection of the plenum to the furnace and all the
ducts connecting to the plenum must be sealed to prevent air leakage.
The sheet metal should be crosshatched to eliminate any popping of
the sheet metal when the indoor fan is energized.
FILTER INSTALLATION
All applications require the use of an internal or external filter. Filter(s)
and the filter retainer are not provided on all models Some models are
shipped with a high velocity filter that must be field installed. A field-supplied internal or external filter and filter retainer hardware must be provided if the filter and the filter retainer are not shipped with the furnace.
Refer to Table 4 for the recommended filter size.
TABLE 5: Filter Sizes
CFM (m3/min)
1200 (33.98)
1200 (33.98)
1200 (33.98)
1600 (45.31)
1200 (33.98)
2000 (56.63)
1600 (45.31)
2000 (56.63)
2000 (56.63)
Input / Output BTU/H (kW)
40/37 (11.71/10.84)
60/48 (17.57/14.07)
80/64 (23.42/18.76)
80/64 (23.42/18.76)
100/80 (29.28/23.42)
100/80 (29.28/23.42)
115/92 (33.70/26.96)
115/92 (33.70/26.96)
130/104 (38.09/30.48)
Cabinet Size
Top Return Filter (in)
Top Return Filter (cm)
A
A
A
B
B
C
C
C
D
(2) 14 x 20
(2) 14 x 20
(2) 14 x 20
(2) 14 x 20
(2) 14 x 20
(2) 14 x 20
(2) 14 x 20
(2) 14 x 20
(2) 14 x 20
(2) 35.6 x 50.8
(2) 35.6 x 50.8
(2) 35.6 x 50.8
(2) 35.6 x 50.8
(2) 35.6 x 50.8
(2) 35.6 x 50.8
(2) 35.6 x 50.8
(2) 35.6 x 50.8
(2) 35.6 x 50.8
FILTER RACK
(factory supplied with some furnaces)
RACK AND FILTERS SECURED
INSIDE BLOWER SECTION
FOR SHIPMENT
CASING SIZE DIMENSION FH
16-1/4”
12-3/4”
22-1/4”
11”
26-1/4”
8-1/4”
NOTE: FILTER ACCESS THROUGH
DUCTWORK MUST BE PROVIDED
FOR REMOVAL AND CLEANING
BRANCH
DUCTS
FILTERS
FILTER
RACK
DUCTWORK
FH
CROSS SECTION A-A
(with Plenum and filters)
FIGURE 3: Downflow Filter
Downflow Filters
A top return filter rack is supplied with the furnace. Two standard filters
are supplied with each unit. Downflow furnaces typically are installed
with the filters located above the furnace, extending into the return air
plenum or duct. Any branch duct (rectangular or round duct) attached to
6
the plenum must attach to the vertical plenum above the filter height.
Refer to Figure 3 for proper installation.
Filters(s) may be located in the duct system external to the furnace
using an external duct filter box attached to the furnace plenum or at the
end of the duct in a return filter grille(s). The use of straps and / or supports is required to support the weight of the external filter box. Refer to
Figures 3 & 4.
If the accessory electronic air cleaner is installed, be sure the air
cleaner is designed to accommodate the furnace CFM (cm/m) and the
air cleaner is installed so it does not obstruct the return airflow. Consideration should be given when locating the air cleaner for maintenance
and temperatures should the indoor fan motor fail to operate. The use
of straps and / or supports is required to support the weight of the electronic air cleaner. It is recommended that the air cleaner not be located
within 12 inches (30.5 cm) from the top of the return air opening on the
furnace. Refer to the instructions supplied with the electronic air
cleaner.
If pleated media air filters or any filter that has a large pressure drop is
installed in the return air duct system be sure that the pressure drop
caused by the air filter will not prevent the furnace from operating within
the rise range specified on the rating plate. If the furnace does not operate within the specified rise range then a larger air filter or an air filter
that has a lower pressure drop must be installed. Refer to figure 3 and
furnace accessories for accessory external filter kit options.
IMPORTANT: For easier filter access in a downflow configuration, a
removable access panel is recommended in the vertical run of the
return air plenum immediately above the furnace.
Unitary Products Group
035-19921-001 Rev. A (0404)
IMPORTANT: Plan your gas supply before determining the correct gas
pipe entry. Use 90-degree service elbow(s), or short nipples and conventional 90-degree elbow(s) to enter through the cabinet access holes.
CLOSET
ELECTRICAL
SUPPLY
RETURN
AIR
CHECKING THE GAS PRESSURES
1.
VENT
PIPE
AIR
FILTERS
2.
3.
4.
5.
6.
GAS SUPPLY
(EITHER SIDE)
The pressure ports on the gas valve are marked OUT P and IN
P.
The manifold pressure must be taken at the port marked OUT P.
The inlet gas supply pressure must be taken at the port marked
IN P.
Using a 3/32” (0.2 cm) Allen wrench, loosen the set screw by
turning it 1 turn counter clockwise. DO NOT REMOVE THE
SET SCREW FROM THE PRESSURE PORT.
Push one end the 3/8” (0.9 cm) ID flexible tubing over the pressure port so that the body of the port is inside the tubing.
Use a reducer connector to connect the 3/8” (0.9 cm) ID flexible
tube to a 1/4” (0.6 cm) ID flexible tube that is connected to a "U”
tube manometer or digital pressure measuring equipment.
TABLE 6: Inlet Gas Pressure Range
FIGURE 4: Return Filter Grill and Return Duct Installation
INLET GAS PRESSURE RANGE
Accessory External Filter Installation
1.
2.
Install the return filter rack on the top of the furnace return air
opening. Secure the filter rack to the front and back flanges with
screws. The return air plenum can be placed over the filter rack
and the branch ducts (rectangular ducts and / or round ducts) can
be attached to the plenum. Route the combustion air and the vent
PVC pipes around the access panels for the filters.
Install the filter(s) provided or you may install Permanente washable filters. Filter should extend through the entire length of the filter rack to prevent air from bypassing the filter. Make sure that any
air filter that is installed in the furnace does not cause an excessive amount of pressure drop. Refer to Table 17 for air filter performance and pressure drops.
IMPORTANT: Air velocity through throwaway type filters must not
exceed 300 feet per minute (1.52 m/m). All velocities over this require
the use of high velocity filters. Refer to Tables 16 and 17.
All installations must have a filter installed.
SECTION IV: GAS PIPING
GAS SAFETY
Natural Gas
4.5” W.C. (1.12 kPa)
10.5” W.C. (2.61 kPa)
Minimum
Maximum
Propane (LP)
8.0” W.C. (1.99 kPa)
13.0” (3.24 kPa) W.C.
IMPORTANT: The inlet gas pressure operating range table specifies
what the minimum and maximum gas line pressures must be for the
furnace to operate safely. The gas line pressure MUST BE a minimum of:
• 7” W.C. (1.74 kPA) for Natural Gas
• 11” W.C. (2.74 kPA) for Propane (LP) Gas
in order to obtain the BTU input specified on the rating plate and/or
the nominal manifold pressure specified in these instructions and on
the rating plate.
GAS PIPING INSTALLATION
Properly sized wrought iron, approved flexible or steel pipe must be
used when making gas connections to the unit. If local codes allow the
use of a flexible gas appliance connection, always use a new listed connector. Do not use a connector that has previously serviced another gas
appliance.
Some utility companies or local codes require pipe sizes larger than the
minimum sizes listed in these instructions and in the codes. The furnace
rating plate and the instructions in this section specify the type of gas
approved for this furnace - only use those approved gases. The installation of a drip leg and ground union is required. Refer to Figure 6.
EXTERNAL MANUAL
SHUTOFF VALVE
An overpressure protection device, such as a pressure regulator,
must be installed in the gas piping system upstream of the furnace
and must act to limit the downstream pressure to the gas valve so it
does not exceed 0.5 PSI (14" w.c. (3.48 kPa). Pressures exceeding
0.5 PSI (14” w.c. (3.48 kPa) at the gas valve will cause damage to
the gas valve, resulting in a fire or explosion or cause damage to
the furnace or some of its components that will result in property
damage and loss of life.
TO GAS
SUPPLY
DRIP
LEG
OUTLET
PRESSURE
PORT
VENT PORT
INLET
WRENCH
BOSS
INLET
PRESSURE
PORT
OUTLET
FF
O
N
O
ON/OFF SWITCH
(Shown in ON position)
MAIN REGULATOR
ADJUSTMENT
TO GAS
SUPPLY
GROUNDED JOINT UNION
MAY BE INSTALLED
INSIDE OR OUTSIDE UNIT.
FIGURE 6: Gas Piping
IMPORTANT: An accessible manual shutoff valve must be installed
upstream of the furnace gas controls and within 6 feet (1.8 m) of the furnace.
The furnace must be isolated from the gas supply piping system by
closing its individual external manual shutoff valve during any pressure
testing of the gas supply piping system at pressures equal to or less
than 1/2 psig (3.5 kPa).
FIGURE 5: Gas Valve
Unitary Products Group
7
035-19921-001 Rev. A (0404)
The unit may also be converted for altitudes up to 10,000 ft. (3048 m)
on natural and propane (LP) gas with additional derate as shown in
Table 7 or refer to ANSI Z223.1 NFPA 54 National Fuel Gas Code or in
Canada CAN/CGA-B149.1-00 Natural Gas and Propane Installation
Code.
The gas valve body is a very thin casting that cannot take any
external pressure. Never apply a pipe wrench to the body of the gas
valve when installing piping. A wrench must be placed on the octagon hub located on the gas inlet side of the valve. Placing a wrench
to the body of the gas valve will damage the valve causing improper
operation and/or the valve to leak.
HIGH ALTITUDE PRESSURE SWITCH CONVERSION
Gas piping may be connected from either side of the furnace using any
of the gas pipe entry knockouts on both sides of the furnace. Refer to
Figure 1 dimensions.
For installation in locations where the altitude is less than 4,500 feet
(1372 m), it is not required that the pressure switch be changed. For
altitudes above 4,500 feet (137 m), refer to Instructions in the Accessory High Altitude Kit.
GAS ORIFICE CONVERSION FOR PROPANE (LP)
This furnace is constructed at the factory for natural gas-fired operation,
but may be converted to operate on propane (LP) gas by using a factory-supplied LP conversion kit. Follow the instructions supplied with
the LP kit. Refer to Table 7 or the instructions in the propane (LP) conversion kit for the proper gas orifice size.
PROPANE AND HIGH ALTITUDE CONVERSION KITS
It is very important to choose the correct kit and/or gas orifices for
the altitude and the type of gas for which the furnace is being
installed.
Only use natural gas in furnaces designed for natural gas. Only use
propane (LP) gas for furnaces that have been properly converted to
use propane (LP) gas. Do not use this furnace with butane gas.
Incorrect gas orifices or a furnace that has been improperly converted will create an extremely dangerous condition resulting in premature heat exchanger failure, excessive sooting, high levels of
carbon monoxide, personal injury, property damage, a fire hazard
and/or death.
High altitude and propane (LP) conversions are required in order
for the appliance to satisfactory meet the application.
An authorized distributor or dealer must make all gas conversions.
In Canada, a certified conversion station or other qualified agency,
using factory specified and/or approved parts, must perform the
conversion.
The installer must take every precaution to insure that the furnace
has been converted to the proper gas orifice size when the furnace
is installed. Do not attempt to drill out any orifices to obtain the
proper orifice size. Drilling out a gas orifice will cause misalignment
of the burner flames, causing premature heat exchanger burnout,
high levels of carbon monoxide, excessive sooting, a fire hazard,
personal injury, property damage and/or death.
LoNOx furnaces requiring propane (LP) gas must have the LoNOx
screens removed prior to installation and operation. See propane
instructions 035-14445-000 or the start up procedure at the back of
these instructions on proper removal of the NOx screens.
HIGH ALTITUDE GAS ORIFICE CONVERSION
This furnace is constructed at the factory for natural gas-fired operation
at 0 – 2,000 ft. (0 m – 610 m) above sea level.
The gas orifices on this furnace must be changed in order to maintain
proper and safe operation, when the furnace is installed in a location
where the altitude is greater than 2,000 ft. (610 m) above sea level on
natural gas or the altitude is greater than 4,000 ft. (1219 m) above sea
level on propane (LP) gas. Refer to Table 7 or the instructions in the
high altitude conversion kit for the proper gas orifice size.
TABLE 7: High Altitude Conversion
Type
Of Gas
Orifice at
Sea Level
2,000 ft.
(610 m)
3,000 ft.
(914 m)
4,000 ft.
(1219 m)
5,000 ft.
(1524 m)
6,000 ft.
(1829 m)
7,000 ft.
(2134 m)
8,000 ft.
(2438 m)
9,000 ft.
(2743 m)
10,000 ft.
(3048 m)
Natural
#45
#46
#47
#47
#47
#48
#48
#49
#49
#50
Propane
#55
#55
#55
#55
#56
#56
#56
#56
#56
#57
SECTION V: ELECTRICAL POWER
Electrical Power Connections
Use copper conductors only.
Field wiring to the unit must be grounded. Electric wires that are field
installed shall conform to the temperature limitation for 63°F (35°C) rise
wire when installed in accordance with instructions. Refer to Table 8 in
these instructions for specific furnace electrical data.
8
Unitary Products Group
035-19921-001 Rev. A (0404)
TABLE 8: Ratings & Physical / Electrical Data - Upflow Models
Input
Output
Nominal
Cabinet Width
Air Temp. Rise
MBH
kW
MBH
kW
CFM
cmm
In.
cm
AFUE
°F
°C
40
11.7
32
9.4
1200
34.0
14-1/2
36.8
80.0
20-50
11-28
60
17.6
48
14.1
1200
34.0
14-1/2
36.8
80.0
25-55
13-31
80
23.5
64
18.8
1200
34.0
14-1/2
36.8
80.0
35-65
19-36
80
23.5
64
18.8
1600
45.3
17 1/2
44.5
80.0
25-55
13-31
100
29.3
80
23.4
1200
34.0
17 1/2
44.5
80.0
40-70
22-39
100
29.3
80
23.4
2000
56.6
21
53.3
80.0
25-55
13-31
115
33.7
92
26.9
1600
45.3
21
53.3
80.0
35-65
19-36
115
33.7
92
26.9
2000
56.6
21
53.3
80.0
30-60
17-33
130
38.1
104
30.5
2000
56.6
24-1/2
62.2
80.0
40-70
22-39
Total
Unit
Max Over-current
Size (awg) @ 75 ft.
Min.
Wire
Operation
WGT.
Input
Max. Outlet
Air Temp
Blower
Size
Blower
Operation
WGT.
MBH
kW
°F
°C
Hp
Amps
In.
cm
amps
protect
one way
LBS
Kg
40
11.7
150
65.6
1/3
6.2
10 x 8
25.4 x 20.3
9.0
20
14
100
45.4
60
17.6
155
68.3
1/3
6.2
10 x 8
25.4 x 20.3
9.0
20
14
110
49.9
80
23.5
165
73.9
1/3
6.2
10 x 8
25.4 x 20.3
9.0
20
14
120
54.4
80
23.5
160
71.1
3/4
11.0
11 x10
27.9 x 25.4
12.0
20
14
130
59.0
100
29.3
170
76.7
1/2
7.0
10 x 8
25.4 x 20.3
12.0
20
14
125
56.7
100
29.3
155
68.3
1
12.2
11 x 10 27.9 x 25.4
14.0
20
12
140
63.5
115
33.7
165
73.9
3/4
11.0
11 x 10 27.9 x 25.4
12.0
20
14
150
68.0
115
33.7
160
71.1
1
12.2
11 x 10 27.9 x 25.4
14.0
20
12
150
68.0
130
38.1
170
76.7
1
12.2
11 x 10 27.9 x 25.4
14.0
20
12
160
72.6
Annual Fuel Utilization Efficiency (AFUE) numbers are determined in accordance with DOE Test procedures.
Wire size and over current protection must comply with the National Electrical Code (NFPA-70-latest edition) and all local codes.
The furnace shall be installed so that the electrical components are protected from water.
SUPPLY VOLTAGE CONNECTIONS
3.
IMPORTANT: The power connection leads and wiring box may be relocated to the left side of the furnace. Remove the screws and cut wire tie
holding excess wiring. Reposition on the left side of the furnace and fasten using holes provided.
L1
HOT
WIRING INSIDE
JUNCTION BOX
N
GRD
WHT
GRN
BLK
BLK/BLK
WHT/WHT
GRN/GRN
JUNCTION
BOX
BLOWER COMPARTMENT
EAC
HEAT
PARK
L1
HUM
XFMR
PARK
VENT PIPE
COOL
2.
Provide a power supply separate from all other circuits. Install
overcurrent protection and disconnect switch per local/national
electrical codes. The switch should be close to the unit for convenience in servicing. With the disconnect or fused switch in the OFF
position, check all wiring against the unit wiring label. Refer to the
wiring diagram in this instruction.
Remove the screws retaining the wiring box cover. Route the
power wiring through the opening in the unit into the junction box
with a conduit connector or other proper connection. In the junction box there will be three wires, a Black Wire, a White Wire and a
Green Wire. Connect the power supply as shown on the unit-wiring label on the inside of the blower compartment door or the wiring schematic in this section. The black furnace lead must be
connected to the L1 (hot) wire from the power supply. The white
furnace lead must be connected to neutral. Connect the green furnace lead (equipment ground) to the power supply ground. An
alternate wiring method is to use a field provided 2” (5.1 cm) x 4”
(10.2 cm) box and cover on the outside of the furnace. Route the
furnace leads into the box using a protective bushing where the
wires pass through the furnace panel. After making the wiring connections replace the wiring box cover and screws. Refer to Figure
7.
The furnace's control system requires correct polarity of the power
supply and a proper ground connection. Refer to Figure 8.
NEUTRALS
1.
IGNITION MODULE
CLASS 2 SYSTEM
CONTROL WIRING
TO THERMOSTAT
Y WR G C
FLUE CHASE
TRANSFORMER
DOOR
SWITCH
BURNER COMPARTMENT
FIGURE 7: Electrical Wiring
LOW VOLTAGE CONTROL WIRING CONNECTIONS
Install the field-supplied thermostat by following the instructions that
come with the thermostat. With the thermostat set in the OFF position
and the main electrical source disconnected, connect the thermostat
wiring from the wiring connections on the thermostat to the terminal
board on the ignition module, as shown in Figure 9. Electronic thermostats may require the common wire to be connected as shown with the
dashed line in Figure 9. Apply strain relief to thermostat wires passing
through cabinet. If air conditioning equipment is installed, use thermostat wiring to connect the Y and C terminals on the furnace control
board to the yellow and brown wires on the condensing unit (unit outside). Refer to Figure 9.
IMPORTANT: Set the heat anticipator in the room thermostat to 0.10
amps. Setting it lower will cause short cycles. Setting it higher will cause
the room temperature to exceed the set points.
Unitary Products Group
9
035-19921-001 Rev. A (0404)
BLK
BLK (HOT)
WHT
WHT (NEUTRAL)
GRN
GRN
NOMINAL
120 VOLT
Before installing the relay and wiring, disconnect electrical power to
both furnaces. Failure to cut power could result in electrical shock
or equipment damage.
FIGURE 8: Line Wiring Connections
ROOM
THERMOSTAT
FURNACE
CONTROL
R
W
G
Y
C
CONDENSING
UNIT
TO AIR CONDITIONER
CONTROLS
R
W
G
Y
C
COMMON T’STAT CONNECTION
FIGURE 9: Heating and Cooling Thermostat Connections
IMPORTANT: Some electronic thermostats do not have adjustable heat
anticipators. They may have other type cycle rate adjustments. Follow
the thermostat manufacturer's instructions.
The 24-volt, 40 VA transformer is sized for the furnace components
only, and should not be connected to power auxiliary devices such as
humidifiers, air cleaners, etc. The transformer may provide power for an
air conditioning unit contactor.
ACCESSORY CONNECTIONS
The furnace control will allow power-switching control of various accessories. Refer to Figure 10, for connection details.
115 VOLT
HUMIDIFIER
HUM. HOT
BLK
WHT
EAC SWITCHED
HUM CIRCUITS
EAC HOT
BLK
115 VOLT
ELECTRONIC WHT
AIR CLEANER
EAC
NEUTRALS
HUM
The relay must not be installed in any location where it could be
exposed to water. If the relay has been exposed to water in any
way, it must not be used.
TWINNING DUCT SYSTEM
Twinned furnaces must only be applied on a common duct system. A
single air supply plenum must be used for both furnaces and coil(s).
Separate plenums and supply ducts systems cannot be utilized. A single return air plenum, common to both furnaces must be used. It is suggested that a return platform be utilized, with bottom air entrance into
each furnace. If a side entrance returns system is used, the common
return duct must be divided equally so as to supply each furnace with
an equal amount of return air.
Both furnaces must be identical models in both heating capacity and
CFM capacity. Both furnaces must be operated on the same motor
speed tap. See typical application, Figure 11.
If furnace staging is desired with two single stage furnaces on a common duct, where the gas burner on the first furnace operates on W1
and the gas burner on the second furnace operates on W2, then the
use of an air-mixing device in the plenum to mix the air from both furnaces is strongly recommended. The mixing device must be installed
before any ducts that supply air to occupied spaces. Twinning causes
both indoor fans to operate simultaneously. If a mixing device is not
used, any ducts that are connected down stream from the furnace that
operates on W2, will be supplying cold air in the Heating mode to the
occupied spaces unless W2 is energized.
VENT PIPE
FIGURE 10: Accessory Connections
ELECTRONIC AIR CLEANER CONNECTION
Two 1/4” (0.64m) spade terminals (EAC and EAC N) for electronic air
cleaner connections are located on the control board. The terminals
provide 115 VAC (1.0 amp maximum) during circulating blower operation.
GAS SUPPLY
(BOTH SIDES)
ELECTRICAL
SUPPLY
1 COIL FOR
EACH FURNACE
HUMIDIFIER CONNECTION
Two 1/4” (0.64 cm) spade terminals (HUM and HUM N) for humidifier
connections are located on the control board. The terminals provide 115
VAC (1.0 amp maximum) during heating system operation.
CO
SU MM
PL PPL ON
EN Y
UM
SUPPLY
AIR
SECTION VI: TWINNING AND STAGING
In applications where more heating capacity or more airflow capacity is
needed than what one furnace can deliver, twinning can be used to
make two furnaces operate in tandem. When two furnaces are installed
using the same duct system, it is very important that the two furnace circulating air blowers operate in unison. If one blower starts before the
second blower, the duct system will become pressurized and the blower
on the second furnace will turn backwards causing the second furnace
to overheat, resulting in damage to the furnace. Twinning is used to
make two furnaces operate in tandem, using one duct system, one
room thermostat and causing both furnaces to turn on and off simultaneously.
10
FIGURE 11: Typical Twinned Furnace Application
IMPORTANT: When two furnaces are twinned, typical system total airflow will be approximately 85% of additive individual furnaces, i.e., two
2000 CFM units will yield a total 3400 CFM.
If a return duct is connected to only one furnace (with a connection
between the two furnaces) an imbalance in the airflow will occur
and the furnace furthest from the return plenum will overheat.
Unitary Products Group
035-19921-001 Rev. A (0404)
GAS PIPING
STAGING
Furnace gas supplies must be provided as specified with these instructions. Since the furnaces are side by side, with no space between, gas
supplies must enter on the right and left respectively. All gas piping
must be in accordance with the national fuel gas code, ANSI Z223.1,
latest edition, and/or all local code or utility requirements.
In applications where more heating capacity or more airflow capacity is
needed than what one furnace can deliver, twinning can be used to
make two furnaces operate in tandem, using one duct system and one
room thermostat. This control can also be used along with a two-stage
wall thermostat to stage two twinned furnaces, making them operate
like a single two-stage furnace. This allows only one furnace to supply
heat during times when the heat output from one furnace is sufficient to
satisfy the demand. When one duct system is used for two furnaces, it
is necessary that the two blowers operate in unison. The twinning function of this board ensures that both blowers turn on and off simultaneously, and operate on the same blower speed. Even when only one
furnace is supplying heat, both furnace blowers must run.
TWINNING
In applications where more heating capacity or more airflow capacity is
needed than what one furnace can deliver, twinning can be used to
make two furnaces operate in tandem, using one duct system and one
room thermostat. When one duct system is used for two furnaces, it is
necessary that the two blowers operate in unison. The twinning function
of the board in this furnace ensures that both blowers turn on and off
simultaneously, and operate on the same blower speed.
Single-Wire Twinning
The control in the furnace has the single-wire twinning feature. With this
feature, a single wire is connected between the TWIN terminal on one
furnace board to the TWIN terminal on the second furnace board. The
board then communicates the blower status from one furnace to the
other along this wire. This communication makes the second furnace
blower come on at the same time, and on the same speed, as the first
furnace blower.
Single-Wire Staging
The single-wire twinning feature of this board can also be used for staging of two furnaces. With this feature, a single wire is connected
between the TWIN terminal on one furnace board to the TWIN terminal
on the second furnace board. The board then communicates the blower
status from one furnace to the other along this wire. This communication makes the second furnace blower come on at the same time, and
on the same speed, as the first furnace blower.
Single-Wire Staging Instructions
Single-Wire Twinning Instructions
Connect the control wiring as shown in the Figure 13.
Connect the control wiring as shown in the diagram below.
1.
1.
Connect the low voltage wiring from the wall thermostat to the terminal strip on the control board of Furnace #1.
2.
Connect a wire from the TWIN terminal of Furnace #1 to the TWIN
terminal of Furnace #2.
3.
Install a separate 24V relay as shown in the diagram below. Use of
this relay is required, as it ensures that the transformers of the two
furnaces are isolated, thus preventing the possibility of any safety
devices being bypassed.
Single-Wire Twinning Operation
Heating - On a call for heat (W signal) from the wall thermostat, both
furnaces will start the ignition sequence and the burners on both furnaces will light. About thirty seconds after the burners light, the blowers
on both furnaces will come on in heating speed. When the thermostat is
satisfied, the burners will all shut off and, after the selected blower off
delay time, both blowers will shut off at the same time. The twinning
control ensures that both blowers come on and shut off at the same
time.
Cooling - On a call for cooling (Y signal) from the wall thermostat, both
furnace blowers will come on at the same time in cooling speed. When
the thermostat is satisfied, both blowers will stay on for 60 seconds,
then will shut off at the same time.
Continuous Fan - On a thermostat call for continuous fan (G signal),
both furnace blowers will come on at the same time in cooling speed
and will stay on until the G signal is removed.
FURNACE 2 CONTROL BOARD
FURNACE 1 CONTROL BOARD
W
W
G
G
C
C
R
TWIN
R
Y
ISOLATION
RELAY
2.
3.
Connect the low voltage wiring from the wall thermostat to the terminal strip on the control board of Furnace #1. For staging applications, the wire from thermostat W1 is connected to the W
connection on the board on Furnace #1. The wire from thermostat
W2 is connected to Furnace #2 through a separate relay, as
described below.
Connect a wire from the TWIN terminal of Furnace #1 to the TWIN
terminal of Furnace #2.
Install a separate 24V relay as shown in the diagram below. Use of
this relay is required, as it ensures that the transformers of the two
furnaces are isolated, thus preventing the possibility of any safety
devices being bypassed.
Single-Wire Staging Operation
Heating - On a call for first-stage heat (W1 signal) from the wall thermostat, Furnace #1 will start the ignition sequence and the burners will
light. About thirty seconds after the burners light, the blowers on both
furnaces will come on in heating speed. When the thermostat is satisfied, the burners will shut off and, after the selected blower off delay
time, both blowers will shut off at the same time. On a call for second
stage of heat, the burners of Furnace #2 will also light and both blowers
will run. The twinning control ensures that both blowers come on and
shut off at the same time.
Cooling - On a call for cooling (Y signal) from the wall thermostat, both
furnace blowers will come on at the same time. When the thermostat is
satisfied, both blowers will stay on for 60 seconds, then will shut off at
the same time.
Continuous Fan - On a thermostat call for continuous fan (G signal),
both furnace blowers will come on at the same time in cooling speed
and will stay on until the G signal is removed.
TWIN
Y
W
W
G
G
C
R
C
TWIN
R
Y
TO A/C
W
G
R
FURNACE 2 CONTROL BOARD
FURNACE 1 CONTROL BOARD
ISOLATION
RELAY
TWIN
Y
Y
WALL THERMOSTAT
FIGURE 12: Single Stage Twinning Wiring Diagram
TO A/C
W1
G
R
Y
W2
WALL THERMOSTAT
FIGURE 13: Two-Stage Twinning Wiring Diagram
Unitary Products Group
11
035-19921-001 Rev. A (0404)
SECTION VII: VENT SYSTEM
CATEGORY 1 - 450 F. MAX. VENT TEMP.
VENT SAFETY
This Category I, furnace is designed for residential application. It may
be installed without modification in a basement, garage, equipment
room, alcove, attic or any other indoor location where all required clearance to combustibles and other restrictions are met.
MORE THAN
10 FT (3.0 M)
3 FT (0.9 m)
MIN.
WALL OR
PARAPET
NOTE: NO
HEIGHT ABOVE
PARAPET REQUIRED
WHEN DISTANCE
FROM WALLS OR
PARAPET IS MORE
THAN 10 FT (3.0 m).
MORE THAN
10 FT (3.0 M)
RIDGE
2 FT(0.6 m)
MIN
CHIMNEY
HEIGHT ABOVE ANY
ROOF SURFACE WITHIN
10 FT (3.0 m) HORIZONTALLY
3 FT (0.9 m)
MIN
The venting system must be installed in accordance with Section 5.3,
Air for Combustion and Ventilation, of the National Fuel Gas Code
Z223.1/NFPA 54 (latest edition), or Sections 7.2, 7.3 or 7.4 of CSA
B149.1, National Gas and Propane Codes (latest edition) or applicable
provisions of the local building code and these instructions.
The furnace shall be connected to any type of B, BW or L vent connector, and shall be connected to a factory-built or masonry chimney. The
furnace shall not be connected to a chimney flue serving a separate appliance designed to burn solid fuel.
The furnace rating plate lists the maximum vent gas temperature. This
temperature must be used to select the appropriate venting materials
and clearances.
It is recommended that the appliance is installed in a location where the
space temperature is 32 °F (0°C) or higher. If the appliance is installed
in a location where the ambient temperature is below 32 °F (0°C), the
combustion by-products could condense causing damage to the appliance heat exchanger.
IMPORTANT: The “VENT SYSTEM” must be installed as specified in
these instructions for Residential and Non HUD Modular Homes.
This appliance may be common vented with another gas appliance for
residential installations as allowed by the codes and standards listed in
these instructions.
Non-HUD approved Modular Homes must be vented with an approved
roof jack and may not be common vented with other appliances.
VENTING
Category I venting consists of vertically venting one or more appliances
in B-vent or masonry chimney (as allowed), using single wall metal pipe
or B-vent connectors. Type B-vent system extends in a general vertical
direction and does not contain offsets exceeding 45 degrees. A vent
system having not more than one 60 degree offset is permitted.
CHIMNEY
FIGURE 14: Vent Termination
VENTING INTO AN EXISTING CHIMNEY
For Category I installations, the furnace shall be connected to a factory
built chimney or vent complying with a recognized standard, or a
masonry or concrete chimney lined with a material acceptable to the
authority having jurisdiction. Venting into an unlined masonry chimney
or concrete chimney is prohibited.
Whenever possible, B-1 metal pipe should be used for venting. Where
use of an existing chimney is unavoidable, the following rules must be
followed:
LOWEST DISCHARGE OPENING
LISTED CAP
LISTED GAS
VENT
12
X
ROOF PITCH
IS X/12
H (min) - MINIMUM HEIGHT FROM ROOF
TO LOWEST DISCHARGE OPENING
1.
The masonry chimney must be built and installed in accordance
with nationally recognized building codes or standards and must
be lined with approved fire clay tile flue liners or other approved
liner material that will resist corrosion, softening, or cracking from
flue gases. THIS FURNACE IS NOT TO BE VENTED INTO AN
UNLINED MASONRY CHIMNEY.
2.
This furnace must be vented into a fire clay tile lined masonry
chimney only if a source of dilution air is provided, such as by common venting with a draft hood equipped water heater. If no source
of dilution air is available, Type B vent must be used, or masonry
chimney vent kit 1CK0603 or 1CK0604 must be used. Refer to the
instructions with the kit to properly apply these masonry chimney
kits.
3.
The chimney must extend at least 3 ft (0.91 m) above the highest
point where it passes through a roof of a building and at least 2 ft
(0.61 higher than any portion of the building with a horizontal distance of 10 ft (3.1 m).
4.
The chimney must extend at least 5 ft (1.5 m) above the highest
equipment draft hood or flue collar. .
FIGURE 15: Vent Termination
TABLE 9: Roof Pitch
ROOF PITCH
Flat to 6/12
6/12 to 7/12
Over 7/12 to 8/12
Over 8/12 to 9/12
Over 9/12 to 10/12
Over 10/12 to 11/12
Over 11/12 to 12/12
Over 12/12 to 14/12
Over 14/12 to 16/12
Over 16/12 to 18/12
Over 18/12 to 20/12
Over 20/12 to 21/12
12
H(min) ft
1.0
1.25
1.5
2.0
2.5
3.25
4.0
5.0
6.0
7.0
7.5
8.0
m
0.30
0.38
0.46
0.61
0.76
0.99
1.22
1.52
1.83
2.13
2.27
2.44
HORIZONTAL SIDEWALL VENTING
For applications where vertical venting is not possible, the only
approved method of horizontal venting is the use of an auxiliary power
vent. Approved power venters are Fields Controls Model SWG-4Y or
Tjernlund Model GPAK-JT. Follow all application and installation details
provided by the manufacturer of the power vent.
Unitary Products Group
035-19921-001 Rev. A (0404)
FAN ASSISTED FURNACE
& WATER HEATER
VENT PIPING ASSEMBLY
FAN ASSISTED
FURNACES
The final assembly procedure for the vent piping is as follows:
EXTERIOR
VENT HOOD
1.
Cut piping to the proper length beginning at the furnace.
2.
Deburr the piping inside and outside.
3.
Dry-fit the vent piping assembly from the furnace to the termination
checking for proper fit support and slope. Piping should be supported with pipe hangers to prevent sagging. The maximum spacing between hangers is 4 f t (1.22 m).
4.
Assemble the vent piping from the furnace to the termination
securing the pipe connections with screws.
OPTIONAL
SIDEWALL
VENT SYSTEM
(field supplied)
VENT
PIPE
HOT
WATER
TANK
FURNACE
VENT CLEARANCES
FIGURE 16: Typical Sidewall Vent Application
VENT
DAMPER
VENT PIPE
IMPORTANT: The vent must be installed with the following minimum
clearances as shown in Figures 14,15 & 22, and must comply with local
codes and requirements.
FLUE
PIPE
TOP
COVER
OPTIONAL
SIDEWALL
VENT SYSTEM
(field supplied)
BURNER
ACCESS
PANEL
CELLAR
WALL
FIGURE 17: Typical Sidewall Vent and Termination Configuration
TABLE 10: Horizontal Sidewall Venting Clearances
Heating
Input
BTU/H
40,000
60,000
80,000
80,000
100,000
100,000
115,000
115,000
130,000
Heating
Input
kW
11.72
17.58
23.44
23.44
29.31
29.31
33.70
33.70
38.10
Heating
Output
BTU/H
32,000
48,000
64,000
64,000
80,000
80,000
92,000
92,000
104,000
Unitary Products Group
Heating
Output
kW
9.38
14.07
18.76
18.76
23.45
23.45
26.96
26.96
30.48
Furnace
Airflow
CFM
1200
1200
1200
1600
1200
2000
1600
2000
2000
Furnace
Airflow
cm/m
33.98
33.98
33.98
45.31
33.98
56.63
45.31
56.63
56.63
Horizontal Vent Length Ft (m) with 4 Elbows
Pipe Size
Min. Vent Length
Max. Vent Length
Inches
cm
Feet
meters
Feet
meters
4
10.16
4.5
1.37
34.5
10.82
4
10.16
4.5
1.37
34.5
10.82
4
10.16
4.5
1.37
34.5
10.82
4
10.16
4.5
1.37
34.5
10.82
4
10.16
4.5
1.37
34.5
10.82
4
10.16
4.5
1.37
34.5
10.82
4
10.16
4.5
1.37
34.5
10.82
4
10.16
4.5
1.37
34.5
10.82
4
10.16
4.5
1.37
34.5
10.82
13
035-19921-001 Rev. A (0404)
VENT CLEARANCES
G
V
A
D
V
E
FIXED
CLOSED
B
I
V
C
V
V
F
B
VENT TERMINAL
X
AIR SUPPLY
B
B
B
L V
V
H
V
V
B
M
AREA WHERE TERMINAL IS NOT PERMITTED
X
V
K
X
J
FIXED
CLOSED
OPERABLE
FIGURE 18: Home Layout
Canadian Installations1
US Installation2
A. Clearance above grade, veranda, porch, deck, or balcony
12 inches (30 cm)
12 inches (30 cm)
B. Clearance to window or door that may be opened
6 inches (15 cm) for applications ≤ 10,000 Btuh (3kW),
12 inches (30 cm) for appliances > 10,000 Btuh (3kW)
and ≤ 100,000 Btuh (30kW), 36 inches (91 cm)
for appliances > 100,000 Btuh (30kW)
6 inches (15 cm) for applications ≤ 10,000 Btuh (3kW),
9 inches (23 cm) for appliances > 10,000 Btuh (3kW)
and ≤ 50,000 Btuh (15kW), 12 inches (30 cm)
for appliances > 50,000 Btuh (30kW)
C. Clearance to permanently closed window
“
“
D. Vertical clearance to ventilated soffit located
above the terminal within a horizontal distance
of 2 feet (61 cm) from the center line of the terminal
“
“
E. Clearance to unventilated soffit
“
“
F. Clearance to outside corner
“
“
G. Clearance to inside corner
“
“
H. Clearance to each side of center line extended
above meter/regulator assembly
3 feet (91 cm) within a height 15 feet (4.5 m) above the
meter/regulator assembly
I. Clearance to service regulator vent outlet
3 feet (91 cm)
J. Clearance to nonmechanical air supply inlet to building
or the combustion air inlet to any other appliance
6 inches (15 cm) for applications ≤ 10,000 Btuh (3kW),
12 inches (30 cm) for appliances > 10,000 Btuh (3kW)
and ≤ 100,000 Btuh (30kW), 36 inches (91 cm)
for appliances > 100,000 Btuh (30kW)
6 inches (15 cm) for applications ≤ 10,000 Btuh (3kW),
9 inches (23 cm) for appliances > 10,000 Btuh (3kW)
and ≤ 50,000 Btuh (15kW), 12 inches (30 cm)
for appliances > 50,000 Btuh (30kW)
K. Clearance to a mechanical supply inlet
6 feet (1.83 m)
3 feet (91 cm) above if within 10 feet (3 cm) horizontally
“
“
L. Clearance above paved sidewalk or paved driveway located on public property 7 feet (2.13 m) †
“
M.Clearance under veranda, porch, deck, or balcony
12 inches (30 cm) ‡
Dryer Vent
3 ft (91.44 cm)
3 ft (91.44 cm)
Plumbing Vent Stack
3 ft (91.44 cm)
3 ft (91.44 cm)
Gas Appliance Vent Terminal
3 ft (91.44 cm) *
3 ft (91.44 cm) *
Vent Termination from any Building Surface
12" (30.4 cm)
12" (30.4 cm)
“
Above Any Grade Level
12" (30.4 cm)
12" (30.4 cm)
Above anticipated snow depth
12" (30.4 cm)
12" (30.4 cm)
Any forced air inlet to the building.
10 ft (304.8 cm)
10 ft (304.8 cm)
The vent shall extend above the highest point where it passes through the roof,
not less than
18" (46 cm)
18" (46 cm)
Any obstruction within a horizontal distance
Not less than 18" (46 cm)
Not less than 18" (46 cm)
1. In accordance with the current CSA B149.1-00, Natural Gas and Propane Installation Code.
2. In accordance with the current ANSI Z223.1 / NFPA 54, National Gas Code.
† A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.
‡ Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor. For clearance not specified in ANSI Z223.1 / NFPA 54 or CSA B149.1-00.
Clearance in accordance with local installation codes and the requirements of the gas supplier and the manufacturer’s Installation Manual.
Any fresh air or make up inlet for dryer or furnace area is considered to be forced air inlet.
Avoid areas where condensate drippage may cause problems such as above planters, patios, or adjacent to windows where steam may cause fogging.
A terminus of a vent shall be either:
Fitted with a cap in accordance with the vent manufacturer’s installation instructions, or In accordance with the installation instructions for a special venting system.
* Does not apply to multiple installations of this furnace model. Refer to "VENTING MULTIPLE UNITS" in this section of these instructions.
IMPORTANT: Consideration must be given for degradation of building materials by flue gases. Sidewall termination may require sealing or shielding of building surfaces with a corrosion resistant
material to protect against combustion product corrosion. Consideration must be given to wind direction in order to prevent flue products and/or condensate from being blown against
the building surfaces. If a metal shield is used it must be a stainless steel material at a minimum dimension of 20 inches. It is recommended that a retaining type collar be used that is
attached to the building surface to prevent movement of the vent pipe.
Responsibility for the provision of proper adequate venting and air supply for application shall rest with the installer.
Vent shall extend high enough above building, or a neighboring obstruction, so that wind from any direction will not create a positive pressure in the vicinity of the vent.
14
Unitary Products Group
035-19921-001 Rev. A (0404)
1.
2.
3.
4.
5.
6.
Observe all clearances listed in vent clearances in these instructions.
Termination should be positioned where vent vapors will not damage plants or shrubs or air conditioning equipment.
Termination should be located where it will not be affected by wind
gusts, light snow, airborne leaves or allow recirculation of flue
gases.
Termination should be located where it will not be damaged or
exposed to flying stones, balls, etc.
Termination should be positioned where vent vapors are not objectionable.
Horizontal portions of the vent system must slope upwards and be
supported to prevent sagging. The vent system may be supported
by the use of clamps or hangers secured to a permanent part of
the structure every 4 ft. (1.22 m).
CHIMNEY OR
GAS VENT
VENTILATION LOUVERS
(each end of attic)
OUTLET
AIR
ALTERNATE
AIR INLET
FAN-ASSISTED COMBUSTION SYSTEM
INLET
AIR
WATER
HEATER
When selecting the location for a horizontal combustion air / vent termination, the following should be considered:
Rooms communicating directly with the space containing the appliances are considered part of the unconfined space, if openings are furnished with doors.
A confined space is an area with less than 50 cu.ft (1.42 m3) per 1,000
Btu/hr (0.2928 kW) input rating for all of the appliances installed in that
area. The following must be considered to obtain proper air for combustion and ventilation in confined spaces.
FURNACE
HORIZONTAL VENT APPLICATIONS AND
TERMINATION
An appliance equipped with an integral mechanical means to either
draw or force products of combustion through the combustion chamber
and/or heat exchanger.
VENTILATION LOUVERS FOR UNHEATED CRAWL SPACE
Ambient Combustion Air Supply
This type installation will draw the air required for combustion from
within the space surrounding the appliance and from areas or rooms
adjacent to the space surrounding the appliance. This may be from
within the space in a non-confined location or it may be brought into the
furnace area from outdoors through permanent openings or ducts. A
single, properly sized pipe from the furnace vent connector to the outdoors must be provided. For upflow models combustion air is brought
into the furnace through the unit top panel opening.
CHIMNEY OR
GAS VENT
VENTILATION LOUVERS
(each end of attic)
VENT PIPE CEMENTS
INTO SOCKET JUST
ABOVE TOP PANEL
WATER
HEATER
OUTLET
AIR
FURNACE
COMBUSTION AIR
FIGURE 20: Atlernate Air Intake, Air Outlet and Chimney Connections
INLET AIR DUCT
[ends 1 ft (30 cm)
above floor]
FIGURE 21: Air Inlet, Outlet and Chimney Connections
Combustion Air Source From Outdoors
FIGURE 19: Combustion Airflow Path Through The Furnace Casing to
the Burner Box
The blocking effects of louvers, grilles and screens must be given consideration in calculating free area. If the free area of a specific louver or
grille is not known, refer to Table 11, to estimate free area.
TABLE 11: Estimated Free Area
Wood or Metal
Louvers or Grilles
This type of installation requires that the supply air to the appliance(s) be of a sufficient amount to support all of the appliance(s)
in the area. Operation of a mechanical exhaust, such as an exhaust
fan, kitchen ventilation system, clothes dryer or fireplace may create conditions requiring special attention to avoid unsatisfactory
operation of gas appliances. A venting problem or a lack of supply
air will result in a hazardous condition, which can cause the appliance to soot and generate dangerous levels of CARBON MONOXIDE, which can lead to serious injury, property damage and / or
death.
Screens+
*
+
Unitary Products Group
Do not use less than 1/4” mesh
Free area or louvers and grille varies widely; the installer should follow louver or grille
manufacturer’s instructions.
Dampers, Louvers and Grilles (Canada Only)
1.
The free area of a supply air opening shall be calculated by subtracting the blockage area of all fixed louvers grilles or screens
from the gross area of the opening.
2.
Apertures in a fixed louver, a grille, or screen shall have no dimension smaller than 0.25” (6.4 mm).
3.
A manually operated damper or manually adjustable louvers are
not permitted for use.
m 3)
An unconfined space is not less than 50 cu.ft (1.42
per 1,000 Btu/
hr (0.2928 kW) input rating for all of the appliances installed in that
area.
Wood 20-25%*
Metal 60-70% *
1/4” (0.635 cm)
mesh or larger 100%
15
035-19921-001 Rev. A (0404)
A automatically operated damper or automatically adjustable louvers shall be interlocked so that the main burner cannot operate
unless either the damper or the louver is in the fully open position.
5.
TABLE 12: Free Area
40,000
Minimum Free Area Required for Each Opening
Vertical Duct or
Round Duct
Horizontal Duct
Opening to Outside
(4,000 BTUH)
(2,000 BTUH)
(4,000 BTUH)
4” (10 cm)
20 in2 (129 cm2)
10 in2 (64 cm2)
60,000
30 in2 (193 cm2)
BTUH Input
Rating
A automatically operated damper or automatically adjustable louvers shall be interlocked so that the main burner cannot operate
unless either the damper or the louver is in the fully open position.
CHIMNEY OR
GAS VENT
2
FURNACE
WATER
HEATER
OPENING
20 in2 (129 cm2)
5” (13 cm)
100,000
50 in2 (322 cm2)
25 in2 (161 cm2)
6” (15 cm)
30 in2 (193 cm2)
7” (18 cm)
2
WATER
HEATER
FURNACE
375 (34.84 m2)
80,000
500 (46.45 m2)
100,000
625 (58.06 m2)
120,000
750 (69.68 m2)
INLET
AIR DUCT
When a Category I furnace is removed or replaced, the original
venting system may no longer be correctly sized to properly vent
the attached appliances.
An improperly sized vent system can cause CARBON MONOXIDE
to spill into the living space causing personal injury, and or death.
GAS
VENT
AIR SUPPLY OPENINGS AND DUCTS
1. An opening may be used in lieu of a duct to provide to provide the outside air
supply to an appliance unless otherwise permitted by the authority having
jurisdiction. The opening shall be located within 12” (30.5 cm) horizontally from,
the burner level of the appliance. Refer to “AIR SOURCE FROM OUTDOORS
AND VENT AND SUPPLY AIR SAFETY CHECK” in these instructions for
additional information and safety check procedure.
VENTILATED
ATTIC
TOP ABOVE
INSULATION
OUTLET
AIR (a)
4. The duct shall terminate within 12 in (30.5 cm) above, and
within 24 in (61 cm) horizontally from, the burner level of
the appliance having the largest input.
GABLE
VENT
5. A square or rectangular shaped duct shall only be used
when the required free area of the supply opening is
2
2
9 in (58.06 cm ) or larger. When a square or rectangular
duct is used, its small dimensionshall not be less than
3 in (7.6 cm).
6. An air inlet supply from outdoors shall be equipped with
a means to prevent the direct entry of rain and wind.
Such means shall not reduce the required free area of
the air supply opening.
An air supply inlet opening from the outdoors shall
be located not less than 12” (30.5 cm) above the
outside grade level.
OUTLET
AIR (b)
INLET
AIR (b)
OUTLET
AIR (a)
GAS
WATER
HEATER
INLET
AIR (a)
COMBUSTION AIR SOURCE FROM OUTDOORS
GAS
VENT
VENTILATED
ATTIC
TOP ABOVE
INSULATION
SOFFIT
VENT
INLET
AIR (b)
GAS
WATER
HEATER
FURNACE
FURNACE
2. The duct shall be either metal, or a material meeting the class 1
requirements of CAN4-S110 Standard for Air Ducts.
3. The duct shall be least the same cross-sectional area as the free
area of the air supply inlet opening to which it connects.
VENTILATED
CRAWL SPACE
7.
60,000
130,000
813 (75.53 m2)
EXAMPLE: Square feet is based on 8 foot ceilings.
28,000 BTUH X 50 Cubic Ft. =
1,400
= 175 Sq. Ft.
1,000
8’ Ceiling Height
FIGURE 23: Horizontal Air Inlet, Outlet and Chimney Connections
GAS
WATER
HEATER
60 in (387 cm )
BTUH Input Rating Minimum Free Area Required for Each Opening
40,000
250 (23.23 m2)
OUTLET
AIR DUCT
SOFFIT
VENT
2
TABLE 13: Unconfined Space Minimum Area in Square Inch
FIGURE 22: Typical Chimney Connections
OPTIONAL
INLET (a)
5” (13 cm)
40 in (258 cm )
7” (18 cm)
130,000
33 in2 (213 cm2)
65 in2 (419 cm2)
EXAMPLE: Determining Free Area.
Appliance
1Appliance
2Total Input
100,000 + 30,000 = (130,000 ÷ 4,000) = 32.5 Sq. In. Vertical
Appliance
1Appliance
2Total Input
100,000 + 30,000 = (130,000 ÷ 2,000) = 65 Sq. In. Horizontal
OPENING
GAS
VENT
15 in2 (97 cm2)
80,000
120,000
GABLE
VENT
2
FURNACE
4.
1. Two permanent openings, one within 12 in (30.5 mm) of the top and
one within 12 in (30.5 mm) of bottom of the confined space, Two
permanent openings, shall communicate directly or by means of ducts
with the outdoors, crawl spaces or attic spaces.
2. One permanent openings, commencing within 12 in (30.5 mm)of the
top of the enclosure shall be permitted where the equipment has
clearances of at least 1 in (2.54 cm) from the sides and back and
6 in (15.24 cm) from the front of the appliance. The opening shall
communicate directly with the outdoors and shall have a minimum
free area of:
a. 1 square in per 3000 Btu per hour (6.45 cm2 0.879 kW) of the total
input rating of all equipment located in the enclosure.
b. Not less than the sum of all vent connectors in the confined space.
3. The duct shall be least the same cross-sectional area as the free
area of the air supply inlet opening to which it connects.
INLET 4. The blocking effects of louvers, grilles and screens must be given
consideration in calculating free area. If the free area of a specific
AIR (a)
louver aor grille is not known.
FIGURE 24: Outside and Ambient Combustion Air
16
Unitary Products Group
035-19921-001 Rev. A (0404)
Vent and Supply (Outside) Air Safety Check Procedure
For Category I furnaces, vent installations shall be in accordance with
Parts 7 and 11 of the National Fuel Gas Code, ANSI Z223.1/NFPA 54,
and or Section 7 and Appendix B of the CSA B149.1, Natural Gas and
Propane Installation Codes, the local building codes, furnace and vent
manufacture's instructions.
Multistory or common venting systems are permitted and must be
installed in accordance with the National Fuel Gas Code, ANSI Z223.1/
NFPA 54 and / or the CSA B149.1, Natural Gas and Propane Installation Codes, local codes, and the manufacture's instructions.
Vent connectors serving Category I furnaces shall not be connected
into any portion of mechanical draft systems operating under positive
pressure.
Horizontal portions of the venting system shall be supported to prevent
sagging using hangers or perforated straps and must slope upwards
not less than 1/4" per foot (0.635 cm/m) from the furnace to the vent terminal.
It is recommended that you follow the venting safety procedure below.
This procedure is designed to detect an inadequate ventilation system
that can cause the appliances in the area to operate improperly causing
unsafe levels of Carbon Monoxide or an unsafe condition to occur.
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 carbonmonxide 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. Inspect the venting system for proper size and horizontal pitch. Determine that there is no blockage, restriction, leakage, corrosion or other
deficiencies, which could cause an unsafe condition
2. Close all building doors and windows and all doors.
3. Turn on clothes dryers and TURN ON any exhaust fans, such as range hoods and bathroom exhausts, so they shall operate at maximum
speed. Open the fireplace dampers. Do not operate a summer exhaust fan.
4. Follow the lighting instructions. Place the appliance being inspected in operation. Adjust thermostat so the appliance shall operate continuously.
5. Test each appliance (such as a water heater) equipped with a draft hood for spillage (down-draft or no draft) at the draft hood relief opening
after 5 minutes of main burner operation. Appliances that do not have draft hoods need to be checked at the vent pipe as close to the
appliance as possible. Use a combustion analyzer to check the CO2 and CO levels of each appliance. Use a draft gauge to check for a
downdraft or inadequate draft condition.
6. After it has been determined that each appliance properly vents when tested as outlined above, return doors, windows, exhaust fans, fireplace dampers and any other gas burning appliance to their normal condition.
7. If improper venting is observed during any of the above tests, a problem exists with either the venting system or the appliance does not
have enough combustion air (Supply Air from outside) to complete combustion. This condition must be corrected before the appliance can
function safely.
NOTE: An unsafe condition exists when the CO reading at the furnace vent exceeds 40 ppm and the draft reading is not in excess of - 0.1 in.
W.C. (-25 kPa) with all of the appliance(s) operating at the same time.
8. Any corrections to the venting system and / or to the supply (outside) air system must be in accordance with the National Fuel Gas Code
Z223.1 or CAN/CGA B149.1-00 Natural Gas and Propane Installation Code (latest editions). If the vent system must be resized, follow the
appropriate tables in Appendix G of the above codes or for this appliance.
SECTION VIII: SAFETY CONTROLS
CONTROL CIRCUIT FUSE
A 3-amp fuse is provided on the control circuit board to protect the 24volt transformer from overload caused by control circuit wiring errors.
This is an ATO 3, automotive type fuse and is located on the control
board.
BLOWER DOOR SAFETY SWITCH
PRESSURE SWITCHES
This furnace is supplied with a pressure switch, which monitors the flow
through the combustion air/vent piping system. This switch de-energizes the ignition control module and the gas valve if any of the following conditions are present. Refer to Figure 25 for tubing connections.
1.
2.
Blockage of vent piping or terminal.
Failure of combustion air blower motor.
This unit is equipped with an electrical interlock switch mounted in the
blower compartment. This switch interrupts all power at the unit when
the panel covering the blower compartment is removed.
Electrical supply to this unit is dependent upon the panel that covers the
blower compartment being in place and properly positioned.
Main power to the unit must still be interrupted at the main power
disconnect switch before any service or repair work is to be done to
the unit. Do not rely upon the interlock switch as a main power disconnect.
Blower and burner must never be operated without the blower
panel in place.
ROLLOUT SWITCH CONTROLS
These controls are mounted on the burner box assembly. If the temperature in the burner box exceeds its set point, the ignition control and the
gas valve are de-energized. The operation of this control indicates a
malfunction in the combustion air blower, heat exchanger or a blocked
vent pipe connection. Corrective action is required. These are manual
reset controls that must be reset before operation can continue.
Unitary Products Group
FIGURE 25: Pressure Switch Tubing Routing
LIMIT CONTROLS
There is high temperature limit control located on the furnace vestibule
panel near the gas valve. This is an automatic reset control that provides over temperature protection due to reduced airflow, that may be
caused by a dirty filter, or if the indoor fan motor should fail. The control
module will lockout if the limit trips 3 consecutive times. Control will
reset and try ignition again after 1 hour.
17
035-19921-001 Rev. A (0404)
SECTION IX: START-UP AND
ADJUSTMENTS
The initial start-up of the furnace requires the following additional
procedures:
IMPORTANT: All electrical connections made in the field and in the factory should be checked for proper tightness.
When the gas supply is initially connected to the furnace, the gas piping
may be full of air. In order to purge this air, it is recommended that the
ground union be loosened until the odor of gas is detected. When gas is
detected, immediately retighten the union and check for leaks. Allow
five minutes for any gas to dissipate before continuing with the start-up
procedure. Be sure proper ventilation is available to dilute and carry
away any vented gas.
NOx SCREEN REMOVAL (Lo-NOx Models Only)
1.
Make sure that the electrical power to the unit is turned off and that
the gas supply is turned off at the shutoff valve.
2.
Remove the blower compartment and burner compartment access
doors.
3.
Disconnect the gas supply piping at the union to permit removal of
the entire burner and gas control assembly from the vestibule
panel. Use the wrench boss on the gas valve when removing or
installing the piping.
4.
Unplug the ignitor from the wire harness. Disconnect the flame
sensor wires located on top of the air shield. Unplug the gas valve
from the wiring harness.
5.
Remove the igintor and ignitor bracket. Handle the ignitor very
carefully since it is fragile and easily broken.
6.
Remove the screws holding the burner assembly to the vestible
panel. It may be necessary to remove the rollout switch bracket(s)
to gain access to one or more of these screws.
7.
Remove the burner assembly. It should be possible to swing the
burner assambly out of the way without disconnecting the remaining wires.
8.
With the burner assembly out of the way, simply slide the NOx
screens out of the heat exchanger tubes and discard the screens.
9.
Replace all components in reverse order. Reconnect all wiring.
TOOLS AND INFORMATION THAT WILL BE
REQUIRED IN ORDER TO PROPERLY PERFORM THE
FURNACE STARTUP PROCEDURE.
1.
Call the local gas supplier to obtain heating value of the natural
gas. If you cannot obtain the heating valve of the gas from the gas
supplier, you may use a default value of 1030 BTU/SCF (38.8 MJ /
m³).
2.
You will need a thermometer or portable digital thermometer to
read the supply and return air temperatures.
3.
You will need a U-tube manometer or digital equipment that has
the ability to read pressures between 0 – 15” in.w.c (0 - 3.73 kPa)
in order to measure the gas line and the manifold pressures.
4.
You will need a 3/32” Allen wrench for the pressure port plugs in
the gas valve.
5.
You will need 2 pieces of 1/8” (0.3 cm) ID flexible tubing that is 12”
(30 cm) in length, 2 – pieces of 1/8” (0.3 cm) tubing that are 4”
(10.0 cm) in length, a 1/8” (0.3 cm) tee and a 1/8” (0.3 cm) adapter
to connect the U-tube manometer or the digital pressure measuring equipment to the gas valve pressure ports.
There is an accessory kit (1PK0601) available from Source 1, which
has the following items:
• 1 - 12” (30 cm) length x 1/8” (0.3 cm) diameter tubing
• 2 – pieces of 4” (10 cm) length x 1/8” (0.3 cm) diameter tubing
• 1 - 5/16” (0.8 cm) tee
• 1 – 5/16” (0.8 cm) x 1/8” (3.175 mm) reducing coupling
• 1 – 1/8” (0.3 cm) adapter
18
There is a accessory kit (1PK0602) available from Source 1, which has
the following items:
• 12” (30 cm) length x 1/8” (0.3 cm) diameter tubing
• 2 – pieces of 4” (10 cm) length x 1/8” (0.3 cm) diameter tubing
• 1 - 5/16” (0.8 cm) tee
• 1 – 5/16” (0.8 cm) x 1/8” (0.3 cm) reducing coupling
• 1 – 1/8” (0.3 cm) adapter
• 1 - Dwyer – Manometer
These items are required in order to properly perform the required startup procedure.
IGNITION SYSTEM SEQUENCE
1.
2.
3.
Turn the gas supply ON at external valve and main gas valve.
Set the thermostat above room temperature to call for heat.
System start-up will occur as follows:
a. The induced draft blower motor will start and come up to
speed. Shortly after inducer start-up, the hot surface igniter
will glow for about 17 seconds.
b.
After this warm up, the ignition module will energize (open)
the main gas valve.
c.
After flame is established, the supply air blower will start in
about 30 seconds.
FIRE OR EXPLOSION HAZARD
Failure to follow the safety warnings exactly could result in serious
injury, death or property damage.
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.
IMPORTANT: Burner ignition may not be satisfactory on first startup
due to residual air in the gas line or until gas manifold pressure is
adjusted. The ignition control will make 3 attempts to light before locking out.
With furnace in operation, check all of the pipe joints, gas valve connections and manual valve connections for leakage using an approved gas
detector, a non-corrosive leak detection fluid, or other leak detection
methods. Take appropriate steps to stop any leak. If a leak persists,
replace the component.
The furnace and its equipment shutoff valve must be disconnected from
the gas supply piping system during any pressure testing of that system
at test pressures in excess of 1/2 PSI (3.45 kPa).
The furnace must be isolated from the gas supply piping system by
closing the equipment shutoff valve during any pressure testing of the
gas supply piping system.
CALCULATING THE FURNACE INPUT
(NATURAL GAS)
NOTE: Burner orifices are sized to provide proper input rate using natural gas with a heating value of 1050 BTU/Ft3 (39.12 MJ/m3). If
the heating value of your gas is significantly different, it may be
necessary to replace the orifices.
NOTE: Front door of burner box must be secured when checking gas
input.
1. Turn off all other gas appliances connected to the gas meter.
2. At the gas meter, measure the time (with a stop watch) it takes to
use 2 cubic ft. (0.0566 m3.) of gas.
3. Calculate the furnace input by using one of the following equations.
Unitary Products Group
035-19921-001 Rev. A (0404)
In the USA use the following formula to calculate the furnace input.
For natural gas multiply the heat content of the gas BTU/SCF (or Default 1030 BTU/SCF, times 2 cubic ft. of gas measured at the gas meter, times a
barometric pressure and temperature correction factor of 0.960; times 3600, then divided by the time (In seconds) it took to measure 2 cubic ft. of gas
from the gas meter.
For propane (LP) gas multiply the heat content of the gas BTU/SCF (or Default 2500 BTU/SCF, times 1 cubic ft. of gas measured at the gas meter,
times a barometric pressure and temperature correction factor of 0.960; times 3600, then divided by the time (In seconds) it took to measure 1 cubic
ft. of gas from the gas meter.
The formula for US input calculation using a cubic foot gas meter:
BTU/f3 x 2 cu.ft. x 0.960 x 3600
Seconds it took to measure the 2 cu.ft. of gas
NATURAL GAS INPUT CALCULATION
EXAMPLE:
1030 x 2 x 0.960 x 3600
90.5
Natural Gas
BTU/SCF 1030
=
BTUH/H
=
79,997.38
BTU/f3 x 2 cu.ft. x 0.960 x 3600
Seconds it took to measure the 2 cu.ft. of gas
PROPANE (LP) GAS INPUT CALCULATION
EXAMPLE:
2500 x 1 x 0.960 x 3600
108
Propane Gas
BTU/SCF 2500
=
BTUH/H
=
80,000.00
In Canada you will use the following formula to calculate the furnace input if you are using a cubic foot gas meter.
For Natural Gas multiply the Heat content of the gas MJ/m3 (or Default 39.2), times 2 cu. ft. of gas x 0.02831 to convert from cubic feet to cubic
meters measured at the gas meter, times a barometric pressure and temperature correction factor of 0.960; times 3600, then divided by the time it
took to measure 2 cu.ft. of gas from the gas meter.
For Propane (LP) Gas multiply the Heat content of the gas MJ/m3 (or Default 93.14), times 1 cu. ft. of gas x 0.02831 to convert from cubic feet to
cubic meters measured at the gas meter, times a barometric pressure and temperature correction factor of 0.960; times 3600, then divided by the
time it took to measure 1 cu.ft. of gas from the gas meter.
The formula for metric input calculation using a cubic foot gas meter:
MJ/m3 x (2 cu.ft. x Conv) x 0.960 x 3600
Seconds it took to measure the 2 cu.ft. of gas
NATURAL GAS INPUT CALCULATION
EXAMPLE:
39.2 x 2 x 0.960 x 3600
90.5
Natural Gas
BTU/SCF 1030 = 39.2 MJ/m3
PROPANE (LP) GAS INPUT CALCULATION
EXAMPLE:
93.15 x 1 x 0.960 x 3600
108
Propane Gas
BTU/SCF 2500+93.15 MJ/m3
=
MJ/H
x
0.2777
=
kW
x
3412.14
=
BTUH/H
=
84.76
x
0.2777
=
23.54
x
3412.14
=
80,312.62
=
84.41
x
0.2777
=
23.45
x
3412.14
=
80,000.00
In Canada use the following formula to calculate the furnace input if you are using a gas meter that measures cubic meters.
For Natural Gas multiply the Heat content of the gas MJ/m3 (or Default 39.2), times 0.0566 m3 of gas measured at the gas meter, times a barometric
pressure and temperature correction factor of 0.960; times 3600, then divided by the time it took to measure 0.0566 m3 of gas from the gas meter.
For Propane (LP) Gas multiply the Heat content of the gas MJ/m3 (or Default 93.14), times 0.00283 m3 of gas measured at the gas meter, times a
barometric pressure and temperature correction factor of 0.960; times 3600, then divided by the time it took to measure 0.0283 cm of gas from the
gas meter.
The formula for metric input calculation using a cubic foot gas meter:
MJ/m3 x (2 cu.ft. x Conv) x 0.960 x 3600
Seconds it took to measure the 2 cu.ft. of gas
NATURAL GAS INPUT CALCULATION
EXAMPLE:
39.2 x 2 x 0.960 x 3600
90.5
Natural Gas
BTU/SCF 1030 = 39.2 MJ/m3
PROPANE (LP) GAS INPUT CALCULATION
EXAMPLE:
93.15 x 1 x 0.960 x 3600
108
Propane Gas
BTU/SCF 2500+93.15 MJ/m3
=
MJ/H
x
0.2777
=
kW
x
3412.14
=
BTUH/H
=
84.76
x
0.2777
=
23.54
x
3412.14
=
80,312.62
=
84.41
x
0.2777
=
23.45
x
3412.14
=
80,000.00
DO NOT ADJUST the manifold pressure regulator if the actual input is equal to or within 8% less than the furnace input specified on the rating plate
or if the furnace rise is above the specified rise range on the rating plate.
If the actual input is significantly higher than the furnace input specified on the rating plate then replace the gas orifice spuds with the gas orifice spuds of the proper size for the type of gas you are using.
For altitudes above 2,000 ft. (610 m) the furnace input MUST BE DERATED. Refer to the GAS CONVERSION FOR PROPANE (LP) AND HIGH
ALTITUDES IN SECTION IV for information on high altitude conversions.
Unitary Products Group
19
035-19921-001 Rev. A (0404)
IMPORTANT: If gas valve regulator is turned in (clockwise), manifold
pressure is increased. If screw is turned out (counterclockwise), manifold pressure will decrease.
Be sure to relight any gas appliances that were turned off at the
start of this input check.
3.
After the manifold pressure has been adjusted, re-calculate the
furnace input to make sure you have not exceeded the specified
input on the rating plate. Refer to “CALCULATING THE FURNACE
INPUT (NATURAL GAS)”.
4.
Once the correct BTU (kW) input has been established, turn the
gas valve to OFF and turn the electrical supply switch to OFF; then
remove the flexible tubing and fittings from the gas valve pressure
tap and tighten the pressure tap plug using the 3/32” Allen wrench.
5.
Turn the electrical and gas supplies back on, and with the burners
in operation, check for gas leakage around the gas valve pressure
port for leakage using an approved gas detector, a non-corrosive
leak detection fluid, or other leak detection methods.
TABLE 14: Inlet Gas Pressure Range
INLET GAS PRESSURE RANGE
Natural Gas
Propane (LP)
Minimum
4.5” W.C. (1.12 kPa)
8.0” W.C. (1.99 kPa)
Maximum
10.5” W.C. (2.61 kPa)
13.0” (3.24 kPa) W.C.
IMPORTANT: The inlet gas pressure operating range table specifies
what the minimum and maximum gas line pressures must be for the furnace to operate safely. The gas line pressure MUST BE a minimum of
• 7” W.C. (1.74 kPA) for Natural Gas
• 11” W.C. (2.74 kPA) for Propane (LP) Gas
in order to obtain the BTU input specified on the rating plate and/or the
nominal manifold pressure specified in these instructions and on the
rating plate.
ADJUSTMENT OF MANIFOLD GAS PRESSURE
Manifold gas pressure may be measured by connecting the “U” tube
manometer to the gas valve with a piece of tubing and on an adapter.
Follow the appropriate section in the instructions below. Refer to Figure
26 for a drawing of the locations of the pressure ports on the gas valve.
Turn gas off at the ball valve or gas cock on gas supply line
before the gas valve. Find the pressure ports on the gas
valve marked Out Pressure Tap and Inlet Pressure Tap.
1.
2.
The manifold pressure must be taken at the port marked OUT
Pressure Tap.
The gas line pressure must be taken at the port marked Inlet Pressure Tap.
The manifold pressure must be checked with the screw-off cap for
the gas valve pressure regulator in place. If not, the manifold pressure setting could result in an over-fire condition. A high manifold
pressure will cause an over-fire condition, which could cause premature heat exchanger failure. If the manifold pressure is too low,
sooting and eventual clogging of the heat exchanger could occur.
Be sure that gas valve regulator cap is in place and burner box to
gas valve pressure reference hose is connected.
MAINFOLD PRESSURE “U” TUBE CONNECTION
OUTLET
PRESSURE TAP
GAS VALVE
1/4” TUBING
MAINIFOLD
PIPE
FLAME
SENSOR
Using a screw driver, remove the cap that covers the manifold pressure
set screw.
3.5 IN
WATER
COLUMN
GAS
PRESSURE
SHOWN
Read the inlet gas pressure
Connect the positive side of the manometer to the adapter previously
installed in the Out pressure Tap on the gas valve. Do not connect any
tubing to the negative side of the manometer, as it will reference atmospheric pressure. Refer to Figure 27 for connection details.
IMPORTANT: The cap for the pressure regulator must be removed
entirely to gain access to the adjustment screw. Loosening or tightening
the cap does not adjust the flow of gas.
NOTE: The regulated outlet pressures, both low and high, have been
calibrated at the factory. Additional pressure adjustment should
not be necessary. If adjustment is necessary, set to the following
specifications. After adjustment, check for gas leakage.
TABLE 15: Nominal Manifold Pressure
NOMINAL MANIFOLD PRESSURE
Natural Gas
3.5" w.c. (0.87 kPa)
Propane (LP) Gas
10.0" w.c. (2.488 kPa)
OUTLET
PRESSURE
PORT
VENT PORT
INLET
WRENCH
BOSS
INLET
PRESSURE
PORT
FIGURE 26: Gas Valve
20
OUTLET
FF
O
N
O
ON/OFF SWITCH
(Shown in ON position)
MAIN REGULATOR
ADJUSTMENT
GAS
BURNERS
U-TUBE
MANOMETER
FIGURE 27: Reading Gas Pressure
ADJUSTMENT OF TEMPERATURE RISE
The temperature rise, or temperature difference between the return
air and the supply (heated) air from the furnace, must be within the
range shown on the furnace rating plate and within the application
limitations shown in Table 8 “ELECTRICAL AND PERFORMANCE
DATA”.
The supply air temperature cannot exceed the “Maximum Supply
Air Temperature” specified in these instructions and on the furnace rating plate. Under NO circumstances can the furnace be
allowed to operate above the Maximum Supply Air Temperature.
Operating the furnace above the Maximum Supply Air Temperature
will cause premature heat exchanger failure, high levels of Carbon
Monoxide, a fire hazard, personal injury, property damage, and/or
death.
The temperature rise, or temperature difference between the return air
and the heated supply air from the furnace, must be within the range
shown on the furnace rating plate and within the application limitations
as shown in Table 8.
After about 20 minutes of operation, determine the furnace temperature
rise. Take readings of both the return air and the heated air in the ducts,
about six feet (1.83 m) from the furnace where they will not be affected
by radiant heat. Increase the blower speed to decrease the temperature
Unitary Products Group
035-19921-001 Rev. A (0404)
rise; decrease the blower speed to increase the rise.
All direct-drive blowers have multi-speed motors. The blower motor
speed taps are located in the control box in the blower compartment.
Refer to Figure 28, and the unit-wiring label to change the blower
speed. To use the same speed tap for heating and cooling, the heat terminal and cool terminal must be connected using a jumper wire and
connected to the desired motor lead. Place all unused motor leads on
Park terminals. Two are provided.
RED-LOW SPEED
BLU-MEDIUM SPEED
BLK-HIGH SPEED
BLK
BLU
RED
MOTOR LEADS
COOL
HEAT
PARK
PARK
LINE
Do not energize more than one motor speed at a time or damage to
the motor will result.
XM
90
120
60
180
FAN OFF
ADJUSTMENT
SWITCHES
ADJUSTMENT OF FAN CONTROL SETTINGS
This furnace is equipped with a time-on/time-off heating fan control. The
fan on delay is fixed at 30 seconds. The fan off delay has 4 settings (60,
90, 120 and 180 seconds). The fan off delay is factory set to 120 seconds. The fan-off setting must be long enough to adequately cool the
furnace, but not so long that cold air is blown into the heated space. The
fan-off timing may be adjusted by positioning the jumper on two of the
four pins as shown in Figure 28.
FIGURE 28: Typical Heat/Cool Speed Tap Connections
FILTER PERFORMANCE
The airflow capacity data published in Table 16 represents blower performance WITHOUT filters. To determine the approximate blower performance of the system, apply the filter drop value for the filter being
used or select an appropriate value from the Table 15.
The filter pressure drop values in Table 15 are typical values for the
type of filter listed and should only be used as a guideline. Actual pressure drop ratings for each filter type vary between filter manufacturers.
TABLE 16: Filter Performance - Pressure Drop Inches W.C. and (kPa)
Airflow Range
CFM
Cm/m
0 - 750
0 - 21.24
Filter Type
Minimum Opening Size
1 Opening
2 Openings
In³
In³
m³
m³
Disposable
1 Opening
inwc
kPa
Hogs Hair*
2 Openings
inwc
kPa
1 Opening
inwc
kPa
Pleated
2 Openings
inwc
kPa
1 Opening
inwc
kPa
230 0.0038
0.01 0.0025
0.01 0.0025
0.15 0.0374
0.2 0.0498
2 Openings
inwc
kPa
751 - 1000
21.27 - 28.32
330 0.0054
0.05 0.0125
0.05 0.0125
1001 - 1250
28.35 - 35.40
330 0.0054
0.1 0.0249
0.1 0.0249
0.2 0.0498
1251 - 1500
35.42 - 42.47
330 0.0054
0.1 0.0249
0.1 0.0249
0.25 0.0623
1501 - 1750
42.50 - 49.55
380 0.0062 658 0.0108 0.15 0.0374 0.09 0.0224 0.14 0.0349 0.08 0.0199 0.3 0.0747 0.17 0.0423
1751 - 2000
49.58 - 56.63
380 0.0062 658 0.0108 0.19 0.0473 0.11 0.0274 0.18 0.0448 0.1 0.0249 0.3 0.0747 0.17 0.0423
2001 & Above 56.66 & Above 463 0.0076 658 0.0108 0.19 0.0473 0.11 0.0274 0.18 0.0448 0.1 0.0249 0.3 0.0747 0.17 0.0423
* Hogs Hair Filters are the type supplied with furnace (if supplied).
APPLYING FILTER PRESSURE DROP TO
DETERMINE SYSTEM AIRFLOW
To determine the approximate airflow of the unit with a filter in place, follow the steps below:
1.
Select the filter type.
2.
Select the number of return air openings or calculate the return
opening size in square inches to determine the proper filter pressure drop.
3.
Determine the External System Static Pressure (ESP) without the
filter.
4.
Select a filter pressure drop from the table based upon the number
of return air openings or return air opening size and add to the
ESP from Step 3 to determine the total system static.
5.
If total system static matches a ESP value in the airflow table (i.e.
0.20 w.c. (50 Pa), 0.60 w.c. (150 Pa), etc,) the system airflow corresponds to the intersection of the ESP column and Model/Blower
Speed row.
6.
If the total system static falls between ESP values in the table (i.e.
0.58 w.c. (144 Pa), 0.75 w.c. (187 Pa), etc.), the static pressure
may be rounded to the nearest value in the table determining the
airflow using Step 5 or calculate the airflow by using the following
example.
Unitary Products Group
Example: For a 130,000 BTUH (38.06 kW) furnace with 2 return openings and operating on high-speed blower, it is found that total system
static is 0.58” w.c. To determine the system airflow, complete the following steps:
Obtain the airflow values at 0.50 w.c. (125 Pa) & 0.60 w.c. (150 Pa)
ESP.
Airflow @ 0.50”: 2125 CFM (60.17 m3/min)
Airflow @ 0.60”: 2035 CFM (57.62 m3/min)
Subtract the airflow @ 0.50 w.c. (125 Pa) from the airflow @ 0.60 w.c.
(150 Pa) to obtain airflow difference.
2035 - 2125 = -90 CFM (2.55 m3/min)
Subtract the total system static from 0.50 w.c. (125 Pa) and divide this
difference by the difference in ESP values in the table, 0.60 w.c.
(150 Pa) - 0.50 w.c. (125 Pa), to obtain a percentage.
(0.58 - 0.50) / (0.60 - 0.50) = 0.8
Multiply percentage by airflow difference to obtain airflow reduction.
(0.8) X (-90) = -72
Subtract airflow reduction value to airflow @ 0.50 w.c. (125 Pa) to
obtain actual airflow @ 0.58 inwc (144 Pa) ESP.
2125 - 72 = 2053
21
035-19921-001 Rev. A (0404)
TABLE 17: Blower Performance CFM - Upflow (without filter)
MODELS
Input/Output/
Airflow/cabinet
0.2 (0.050)
0.3 (0.075)
cm/m cfm cm/m cfm cm/m
0.4 (0.099)
0.5 (0.124)
0.6 (0.149)
cfm
cfm
cfm cm/m cfm cm/m cfm
cm/m
cm/m
0.7 (0.174)
0.8 (0.199)
0.9 (0.224) 1.0 (0.249)
cm/m
cfm
cm/m
cfm cm/m
1580 44.7 1530 43.3 1470 41.6 1405 39.8 1330 37.7 1245 35.3 1150 32.6 1045 29.6
890
25.2
650
18.4
MED-HIGH 1110
31.4 1100 31.1 1075 30.4 1060 30.0 1030 29.2
980
27.8
920
26.1
835
23.6
680
19.3
520
14.7
MED-LOW
845
23.9
840
23.8
830
23.5
815
23.1
790
22.4
750
21.2
670
19.0
595
16.8
480
13.6
320
9.1
LOW
675
19.1
665
18.8
660
18.7
645
18.3
620
17.6
585
16.6
530
15.0
455
12.9
360
10.2
255
7.2
HIGH
1970 55.8 1935 54.8 1900 53.8 1850 52.4 1795 50.8 1735 49.1 1660 47.0 1590 45.0 1495 42.3 1395 39.5
80/64/1600/"B" †
100/80/1200/"B" †
100/80/1600/"B" †
115/92/1600/"C"
80/64/2200/"C"
0.1 (0.025)
cfm
HIGH
40/32/1200/"A" †
60/48/1200/"A" †
80/64/1200/"A" †
EXTERNAL STATIC PRESSURE, INCHES WC (kPa)
Speed
Tap
MED
1445 40.9 1435 40.6 1425 40.4 1415 40.1 1405 39.8 1375 38.9 1350 38.2 1300 36.8 1240 35.1 1160 32.8
LOW
1245 35.3 1235 35.0 1225 34.7 1215 34.4 1205 34.1 1190 33.7 1170 33.1 1135 32.1 1090 30.9
995
28.2
HIGH
1675 47.4 1645 46.6 1595 45.2 1530 43.3 1465 41.5 1385 39.2 1280 36.2 1155 32.7 1025 29.0
810
22.9
MED
1270 36.0 1260 35.7 1250 35.4 1240 35.1 1215 34.4 1185 33.6 1125 31.9 1035 29.3
910
25.8
695
19.7
LOW
955
685
19.4
510
14.4
HIGH
2050 58.0 1990 56.4 1935 54.8 1860 52.7 1770 50.1 1680 47.6 1580 44.7 1490 42.2 1370 38.8 1255 35.5
27.0
950
26.9
945
26.8
935
26.5
920
26.1
905
25.6
865
24.5
810
22.9
MED
1630 46.2 1615 45.7 1600 45.3 1585 44.9 1550 43.9 1510 42.8 1445 40.9 1355 38.4 1270 36.0 1135 32.1
LOW
1340 37.9 1325 37.5 1310 37.1 1295 36.7 1285 36.4 1270 36.0 1245 35.3 1195 33.8 1125 31.9 1005 28.5
HIGH
2040 57.8 1975 55.9 1925 54.5 1855 52.5 1780 50.4 1695 48.0 1610 45.6 1505 42.6 1380 39.1 1225 34.7
MED
1725 48.8 1685 47.7 1650 46.7 1610 45.6 1555 44.0 1500 42.5 1425 40.4 1340 37.9 1220 34.5 1075 30.4
LOW
1365 38.7 1355 38.4 1325 37.5 1290 36.5 1265 35.8 1250 35.4 1210 34.3 1140 32.3 1045 29.6
HIGH
2533 71.7 2442 69.1 2355 66.7 2279 64.5 2193 62.1 2110 59.7 2009 56.9 1895 53.7 1790 50.7 1670 47.3
940
26.6
MED-HIGH 1978 56.0 1942 55.0 1906 54.0 1869 52.9 1819 51.5 1754 49.7 1694 48.0 1617 45.8 1521 43.1 1402 39.7
MED-LOW 1566 44.3 1544 43.7 1514 42.9 1475 41.8 1443 40.9 1419 40.2 1377 39.0 1317 37.3 1245 35.3 1141 32.3
100/80/2000/"C" †
115/92/2000/"C" †
130/104/2000/"D" †
LOW
1281 36.3 1262 35.7 1243 35.2 1198 33.9 1168 33.1 1135 32.1 1103 31.2 1047 29.6
HIGH
2400 68.0 2320 65.7 2275 64.4 2200 62.3 2115 59.9 2025 57.3 1930 54.7 1825 51.7 1700 48.1 1570 44.5
988
28.0
912
25.8
MED
2050 58.0 2025 57.3 1980 56.1 1930 54.7 1855 52.5 1805 51.1 1720 48.7 1635 46.3 1530 43.3 1400 39.6
LOW
1690 47.9 1675 47.4 1660 47.0 1630 46.2 1610 45.6 1560 44.2 1500 42.5 1430 40.5 1330 37.7 1225 34.7
HIGH
2380 67.4 2330 66.0 2270 64.3 2205 62.4 2120 60.0 2025 57.3 1920 54.4 1815 51.4 1705 48.3 1565 44.3
MED
2040 57.8 2010 56.9 1980 56.1 1920 54.4 1875 53.1 1790 50.7 1705 48.3 1610 45.6 1515 42.9 1385 39.2
LOW
1690 47.9 1680 47.6 1655 46.9 1630 46.2 1590 45.0 1530 43.3 1490 42.2 1425 40.4 1350 38.2 1235 35.0
HIGH
2405 68.1 2340 66.3 2275 64.4 2210 62.6 2130 60.3 2050 58.0 1955 55.4 1840 52.1 1725 48.8 1600 45.3
NOTE: Data below reflects airflows with two return openings - two sides or one side and bottom
80/64/2000/"C"
100/80/2000/"C" †
115/92/2000/“C" †
130/104/2000/"D" †
MED
2005 56.8 1990 56.4 1965 55.6 1935 54.8 1880 53.2 1815 51.4 1725 48.8 1635 46.3 1535 43.5 1410 39.9
LOW
1655 46.9 1640 46.4 1625 46.0 1610 45.6 1585 44.9 1540 43.6 1485 42.1 1420 40.2 1340 37.9 1235 35.0
HIGH
2385 67.5 2335 66.1 2275 64.4 2195 62.2 2120 60.0 2040 57.8 1935 54.8 1820 51.5 1700 48.1 1555 44.0
MED
2005 56.8 1980 56.1 1955 55.4 1905 53.9 1845 52.2 1775 50.3 1700 48.1 1610 45.6 1500 42.5 1370 38.8
LOW
1640 46.4 1635 46.3 1620 45.9 1605 45.4 1575 44.6 1540 43.6 1480 41.9 1400 39.6 1330 37.7 1225 34.7
NOTES:
1. Airflow expressed in standard cubic feet per minute (CFM) and in cubic meters per minute (m3/min).
2. Return air is through side opposite motor (left side).
3. Airflows above 1800 CFM (50.97 m3/min) require either return from two sides or one side plus bottom.
4. Motor voltage at 115 V.
* Input / Output / CFM / Cabinet Width (A=14-1/2, B=17-1/2, C=21, D=24-1/2)
† Indicates model available in LoNOx.
TABLE 18: Field Installed Accessories - Non Electrical
22
MODEL NO.
DESCRIPTION
USED WITH
1NP0805
1NP0806
1LN0802
1FF0110
1FF0112
1HA0802
PROPANE (LP) CONVERSION KIT
PROPANE (LP) CONVERSION KIT
LOW NOX KIT
FILTER FRAME KIT
FILTER FRAME KIT
HIGH ALTITUDE INSTRUCTION PACKET (DOES NOT INCLUDE ORIFICES)
08, 12
16, 20
ALL MODELS
08 thru 12
16 thru 20
ALL MODELS
Unitary Products Group
035-19921-001 Rev. A (0404)
SECTION X: WIRING DIAGRAM
FIGURE 29: Wiring Diagram
Unitary Products Group
23
NOTES
Subject to change without notice. Printed in U.S.A.
Copyright © by York International Corp. 2004. All rights reserved.
Unitary
Product
Group
035-19921-001 Rev. A (0404)
Supersedes: 035-17405-001 Rev. A (0702), 035-17405-002 Rev. A (0204)
5005
York
Drive
Norman
OK
73069
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