Modulating Condensing Gas Furnaces With Variable Speed Blowers - 97% + AFUE
INSTALLATION INSTRUCTIONS
*MQ Upflow / Horizontal Model
WARNING:
FIRE OR EXPLOSION HAZARD
•Failure to follow safety warnings exactly could
result in serious injury or property damage.
•Installation and service must be performed
by a qualified installer, service agency or the
gas supplier.
•Do not store or use gasoline or other
flammable vapors and liquids in the vicinity
of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
•Do not try to light any appliance.
•Do not touch any electrical switch; do not
use any phone in your building.
•Leave the building immediately.
•Immediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s
instructions.
•If you cannot reach your gas supplier, call
the fire department.
AVERTISSEMENT
RISQUE D’INCENDIE OU D’ EXPLOSION
•Le non-respect des avertissements de
sécurité pourrait entraîner des blessures
graves, la mort ou des dommages matériels.
•L’installation et l’entretien doivent être
effectués par un installateur qualifié, un
organisme de service ou le fournisseur de
gazstaller, service agency or the gas supplier.
•Ne pas entreposer ni utiliser de l’essence ni
d’autres vapeurs ou liquides inflammables
dans le voisinage de cet appareil, ni de tout
autre appareil.
QUE FAIRE S’IL Y A UNE ODEUR DE GAZ
•Ne pas tenter d’allumer aucun appareil.
•Ne toucher à aucun interrupteur électrique;
n’utiliser aucun téléphone dans le bâtiment.
•Évacuer l’immeuble immédiatement.
•Appeler immédiatement le fournisseur de
gaz en employant le téléphone d’un voisin.
Respecter à la lettre les instructions du
fournisseur de gaz.
•Si personne ne répond, appeler le service des
incendies.
DO NOT DESTROY THIS MANUAL. KEEP IN A SAFE PLACE FOR FUTURE REFERENCE.
NOTE TO INSTALLER: This installlation manual focuses on installing the MQ furnace in a single zone only. The
MQ furnace may also be installed with the iQ Zone zoning system. The installation of the furnace itself does not
change. Additional details, such as the duct/damper design, and the low voltage wiring may be found in the following
publications:
•iQ Drive System Field Wiring Instructions
•Airzone iQ Zone Installation Manual
TABLE OF CONTENTS
IMPORTANT SAFETY INFORMATION......................3
REQUIREMENTS & CODES......................................4
Combustion Air Quality.............................................5
Heating Load............................................................5
Operation of Furnace During Construction..............6
Installation in a Garage............................................6
Clearances to Combustible Materials.......................6
COMBUSTION AIR & VENTING REQUIREMENTS . 7
Direct Vent Furnaces................................................8
Conventional Vent Systems - Confined Spaces.......8
Air From Inside......................................................9
Outdoor Air from a Crawl Space or Vented Attic...9
Outdoor Air Using Vertical Ducts...........................9
Outdoor Air Using Horizontal Ducts......................9
Air Directly Through an Exterior Wall....................9
Alternate Method of Providing Air from Outside:...10
Conventional Vent Systems - Unconfined Spaces...10
Category IV Venting.................................................10
Vent Pipe Material.................................................11
Vent Pipe Length & Diameter................................11
Vent Pipe Installation.............................................12
Outdoor Terminations - Horizontal Venting............12
Outdoor Terminations - Vertical Venting................13
Vent Freezing Protection.......................................13
Existing Installations.............................................14
Condensate Disposal...............................................14
CIRCULATING AIR REQUIREMENTS.......................14
Plenums & Air Ducts................................................14
Return Air Connections............................................15
Upflow & Horizontal Furnaces..............................15
Downflow Furnaces..............................................15
Supply Air Connections............................................15
Acoustical Treatments..............................................15
FURNACE INSTALLATION........................................16
General Requirements.............................................16
Upflow Installation....................................................16
Horizontal Installation...............................................16
Bottom Panel Removal.............................................16
Alternate Bottom Panel Removal..........................17
2
Inducer & Venting Options........................................17
Inducer Assembly Rotation......................................17
Accessories..............................................................18
Finish Flange........................................................18
Rubber Grommets................................................18
PVC Components.................................................18
Typical Orientation...........................................18
Alternate Orientation........................................18
Condensate Drain Lines.......................................19
Pressure Switch Tubing............................................20
GAS SUPPLY & PIPING.............................................21
Leak Check..............................................................21
High Altitude Application..........................................22
Conversion to LP/Propane.......................................23
ELECTRICAL WIRING................................................23
Line Voltage Wiring...................................................24
Thermostat / Low Voltage Connections....................24
Single Stage AC....................................................24
Two - Stage AC.....................................................24
Single Stage Heat Pump.......................................24
Two - Stage Heat Pump........................................24
Grounding................................................................26
START-UP & ADJUSTMENTS....................................26
Pre-Start Check List.................................................26
System Configuration...............................................27
Start-up Procedures.................................................27
Verifying & Adjusting the Input Rate.........................27
Verifying & Adjusting Temperature Rise...................27
Verifying Burner Operation.......................................28
Verifying Operation of the Supply Air Limit Switch...28
OPERATING SEQUENCE..........................................28
Heating Cycle...........................................................28
Cooling Cycle...........................................................29
Fan Mode.................................................................29
Intermittent Fan Mode..............................................29
MAINTENANCE..........................................................29
TROUBLESHOOTING................................................30
FIGURES & TABLES..................................................31
Figure 22. *MQ Cabinet Dimensions.....................31
Airflow Data..............................................................31
Table 7. Modulating Furnace CFM Targets...........31
Gas Information........................................................32
Table 8. Gas Flow Rates.......................................32
Table 9. Gas Pipe Capacities................................32
Electrical Diagrams..................................................33
Table 10. Wire Length & Voltage Specifications....33
Figure 23. Variable Speed Motor Control Board....33
Figure 24. Modulating Furnace Control Board......33
Figure 25. Wiring Diagram for Variable Speed
Modulating Furnaces...........................34
Venting Information..................................................35
Table 11. Vent Termination Clearances.................35
Figure 26. Vent Pipe & Condensate Options Upflow Furnaces..................................36
Figure 27. Vent Pipe & Condensate Options Horizontal Furnaces.............................37
Figure 28. Horizontal & Vertical Venting Options...38
FURNACE COMPONENTS........................................39
INSTALLATION / PERFORMANCE CHECK LIST.....40
IMPORTANT SAFETY INFORMATION
INSTALLER: Please read all instructions before servicing
this equipment. Pay attention to all safety warnings and
any other special notes highlighted in the manual. Safety
markings are used frequently throughout this manual to
designate a degree or level of seriousness and should
not be ignored.
WARNING - indicates a potentially hazardous situation
that if not avoided, could result in personal injury or death.
CAUTION - indicates a potentially hazardous situation
that if not avoided, may result in minor or moderate injury
or property damage.
WARNING:
The safety information listed in this manual must
be followed during the installation, service, and
operation of this unit. Unqualified individuals
should not attempt to interpret these instructions
or install this equipment. Failure to follow safety
recommendations could result in possible
damage to the equipment, serious personal
injury or death.
WARNING:
Unless otherwise noted in these instructions,
only factory authorized kits or accessories may
be used with or when modifying this product.
WARNING:
Improper installation, service, adjustment, or
maintenance may cause explosion, fire, electrical
shock or other hazardous conditions which may
result in personal injury or property damage.
Unless otherwise noted in these instructions,
only factory authorized kits or accessories may
be used with this product.
WARNING:
Do not install this furnace if any part has been
submerged under water. A flood damaged furnace
is extremely dangerous. Attempts to use the
furnace may result in fire or explosion. A qualified
service agency should be contacted to inspect the
furnace and to replace any electrical or control
system parts that have been wet or under water.
•To minimize equipment failure or personal injury, it is
essential that only qualified individuals install, service,
or maintain this equipment. If you do not posses
mechanical skills or tools, call your local dealer for
assistance.
•Follow all precautions in the literature, on tags, and
on labels provided with the equipment. Read and
thoroughly understand the instructions provided with
the equipment prior to performing the installation and
operational checkout of the equipment.
•Use caution when handling this appliance or removing
components. Personal injury can occur from sharp metal
edges present in all sheet metal constructed equipment.
•Do not store any of the following on, or in contact with,
the unit: Rags, brooms, vacuum cleaners, or other
cleaning tools, spray or aerosol cans, soap powders,
bleaches, waxes, cleaning compounds, plastics or
plastic containers, paper bags or other paper products,
gasoline, kerosene, cigarette lighter fluid, dry cleaning
fluids, paint thinners, or other volatile fluids.
• The installer should become familiar with the units wiring
diagram before making any electrical connections to
the unit. See Figure 25, (page 34) or the unit wiring
label.
•Always reinstall the doors on the indoor blower after
servicing or cleaning/changing the filters. Do not operate
the indoor blower without all doors and covers in place.
3
REQUIREMENTS & CODES
WARNING:
The safety information listed below must be
followed during the installation, service, and
operation of this furnace. Failure to follow safety
recommendations could result in possible
damage to the equipment, serious personal
injury or death.
•This furnace must be installed in accordance with
these instructions, all applicable local building codes
and the current revision of the National Fuel Gas Code
(NFPA54/ANSI Z223.1) or the Natural Gas and Propane
Installation Code, CAN/CGA B149.1.
•Use only with type of gas approved for this furnace.
Refer to the furnace rating plate.
•Install this furnace only in a location and position as
specified in Figure 1, (page 6).
•Provide adequate combustion and ventilation air to the
furnace space as specified on pages 7 - 10.
•Provide adequate clearances around the vent air intake
terminal as specified in Figure 7, Figure 8, (page 12),
Figure 9, (page 13), & Figure 10, (page 13)
•Combustion products must be discharged outdoors.
Connect this furnace to an approved vent system only,
as specified on pages 10 - 14.
•Never test for gas leaks with an open flame. Use a
commercially available soap solution to check all
connections. See pages 21 - 22.
•This furnace is designed to operate with a maximum
external pressure rise of 0.5 inches of water column.
Consult Table 7, (page 31) and the rating plate for
the proper circulating air flow and temperature rise. It is
important that the duct system be designed to provide
the correct flow rates and external pressure rise. An
improperly designed duct system can result in nuisance
shutdowns, and comfort or noise issues.
•When 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 in the conditioned space.
See pages 14 - 15.
•A gas-fired furnace for installation in a residential garage
must be installed as specified on page 6.
•This furnace may be used for temporary heating of
buildings or structures under construction. See the
guidelines listed on page 6.
•The Commonwealth of Massachusetts requires
compliance with regulation 248 CMR 4.00 and 5.00 for
installation of through – the – wall vented gas appliances
as follows:
4
1. For direct-vent appliances, mechanical-vent heating
appliances or domestic hot water equipment, where
the bottom of the vent terminal and the air intake is
installed below four feet above grade the following
requirements must be satisfied:
a.) A carbon monoxide (CO) detector and alarm shall
be placed on each floor level where there are
bedrooms. The detector shall comply with NFPA
720 (2005 Edition) and be mounted in the living
area outside the bedroom(s).
b.) A (CO) detector shall be located in the room that
houses the appliance or equipment and shall:
• Be powered by the same electrical circuit as
the appliance or equipment. Only one service
switch shall power the appliance and the (CO)
detector;
• Have battery back-up power;
• Meet ANSI/UL 2034 Standards and comply
with NFPA 720 (2005 Edition); and Approved
and listed by a Nationally Recognized Testing
Laboratory as recognized under 527 CMR.
c.) A Product-approved vent terminal must be used,
and if applicable, a product-approved air intake must
be used. Installation shall be in strict compliance
with the manufacturer’s instructions. A copy of
the installation instructions shall remain with the
appliance or equipment at the completion of the
installation.
d.) A metal or plastic identification plate shall be
mounted at the exterior of the building, four feet
directly above the location of vent terminal. The
plate shall be of sufficient size, easily read from
a distance of eight feet away, and read “Gas Vent
Directly Below”.
2. For direct-vent appliances, mechanical-vent heating
appliances or domestic hot water equipment where
the bottom of the vent terminal and the air intake is
installed above four feet above grade the following
requirements must be satisfied: a.) A (CO) detector and alarm shall be placed on each
floor level where there are bedrooms. The detector
shall comply with NFPA 720 (2005 Edition) and be
mounted in the living area outside the bedroom(s).
b.) The (CO) detector shall:
• Be located in the room that houses the
appliance or equipment;
• Be hard-wired or battery powered or both.
• Shall comply with NFPA 720 (2005 Edition).
c.) A product-approved vent terminal must be used,
and if applicable, a product-approved air intake must
be used. Installation shall be in strict compliance
with the manufacturer’s instructions. A copy of
the installation instructions shall remain with the
appliance or equipment at the completion of the
installation.
The information listed below is for reference purposes only
and does not necessarily have jurisdiction over local or state
codes. Always consult with local authorities before installing
any gas appliance.
Combustion & Ventilation Air
• US: National Fuel Gas Code (NFGC), Air for Combustion
and Ventilation
• CANADA: Natural Gas and Propane Installation Codes
(NSCNGPIC), Venting Systems and Air Supply for
Appliances
Duct Systems
• US and CANADA: Air Conditioning Contractors Association
(ACCA) Manual D, Sheet Metal and Air Conditioning
Contractors National Association (SMACNA), or American
Society of Heating, Refrigeration, and Air Conditioning
Engineers (ASHRAE) Fundamentals Handbook
Electrical Connections
• US: National Electrical Code (NEC) ANSI/NFPA 70
• CANADA: Canadian Electrical Code CSA C22.1
Gas Piping & Gas Pipe Pressure Testing
• US: NFGC and National Plumbing Codes
• CANADA: NSCNGPIC
General Installation
• US: Current edition of the NFGC and the NFPA 90B. For
copies, contact the National Fire Protection Association Inc.,
Batterymarch Park, Quincy, MA 02269; or American Gas
Association, 400 N. Capitol, N.W., Washington DC 20001
or www.NFPA.org
• CANADA: NSCNGPIC. For a copy, contact Standard Sales,
CSA International, 178 Rexdale Boulevard, Etobicoke
(Toronto), Ontario, M9W 1R3 Canada
Safety
• US: (NFGC) NFPA 54–1999/ANSI Z223.1 and the Installation
Standards, Warm Air Heating and Air Conditioning Systems
ANSI/NFPA 90B.
• CANADA: CAN/CGA-B149.1 and .2–M00 National Standard
of Canada. (NSCNGPIC)
Combustion Air Quality
CAUTION:
Combustion air must not be drawn from a
corrosive atmosphere.
To maximize heat exchanger life, the combustion air
must be free of chemicals that can form corrosive acidic
compounds in the combustion gases. The recommended
source of combustion air is to use outdoor air. However,
the use of indoor air in most applications is acceptable
except as listed:
•If the furnace is installed in a confined space, it is
required that the necessary combustion air come from
the outdoors by way of attic, crawl space, air duct, or
direct opening. For Installations in confined spaces, see
page 8 for combustion air requirements.
•Installations in these locations may require outdoor air
for combustion, due to chemical exposures:
Commercial buildings
Buildings with indoor pools
Furnaces installed in laundry rooms
Furnaces installed in hobby or craft rooms
•Exposure to the following substances in the combustion
air supply may require outdoor air for combustion:
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 (perchloroethylene)
Printing inks, paint removers, varnishes, etc.
Hydrochloric Acid
Cements and glues
Antistatic fabric softeners
Masonry acid washing materials
Heating Load
This furnace should be sized to provide the design heating
load requirement. Heating load estimates can be made
using approved methods available from Air Conditioning
Contractors of America (Manual J); American Society of
Heating, Refrigerating, and Air Conditioning Engineers;
or other approved engineering methods. Excessive
oversizing of the furnace could cause the furnace
and/or vent to fail prematurely. The ductwork should
be appropriately sized to the capacity of the furnace to
ensure its proper airflow rating.
Zoned systems may increase undesirable effects of
oversizing. Extra care must be taken when estimating
the heating load for zoned installations.
For installations above 2,000 ft., the furnace should have
a sea level input rating large enough that it will meet the
heating load after deration for altitude.
The *MQ modulating furnace is capable of controlling
its heat output to meet different heating loads. With 11
available continuous heat outputs (or “steps”), the MQ
furnace can function like 11 different furnaces.
A step defines the gas input rate, an inducer blower speed,
and circulating air flow. Steps 1 -11 cover input rates
from 50% to 100% of the furnaces maximum input rate.
The furnace begins at step 6 (or 75% of full rate) for 30
seconds and then goes to step 1 (or 50%). Afterwards,
the iQ Drive® thermostat periodically reevaluates the
heat output needed and changes the step accordingly.
If the heating load is less than 50% of maximum, the
furnace turns off and on to a fixed 15 minute cycle. There
are 5 additional steps that use different on and off times.
The iQ Drive® thermostat automatically adjusts how long
the furnace is on during each cycle. Overall, the iQ Drive®
thermostat can control the heat delivered to the residence
down to 1/7th of the maximum input rate.
5
Installation in a Garage
CAUTION:
6
Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any
other appliance. Storage of or use of gasoline or
other flammable vapors or liquids in the vicinity
of this or any appliance can result in serious
injury or death.
The *MQ Gas-fired furnace may be installed in a residential
garage with the provision that the burners and igniter are
located no less than 18 inches (457mm) above the floor.
The furnace must be located or protected to prevent
physical damage by vehicles.
Clearances to Combustible Materials
This furnace is Design Certified in the U.S. and Canada
by CSA International for the minimum clearances to
combustible material listed in Figure 1. To obtain model
number and specific clearance information, refer to the
furnace rating plate, located inside of the furnace cabinet.
Access for positioning and servicing the unit must be
considered when locating unit. The need to provide
clearance for access to panels or doors may require
clearance distances over and above the requirements.
Allow 24 inches minimum clearance from the front of
the unit. However 36 inches is strongly recommended.
FigureCLEARANCES
1
INSTALLATION
UPFLOW
APPLICATIONS
BACK
FRONT
FRONT
BOTTOM
SIDE
TOP
TOP
HORIZONTAL
APPLICATIONS
VENT
LEFT SIDE
Operating gas furnaces in construction environments can
cause a variety of problems with the furnace. Proper use
of commercial portable space heating equipment during
construction is recommended. This gas furnace may be
used during construction if it is not in violation of any
applicable codes and the following criteria are met:
•The installation must meet all applicable codes. The
furnace must be permanently installed according to the
instructions supplied with the furnace including electrical
supply, gas supply, duct work and venting. The furnace
must be controlled by a thermostat properly installed
according to the instructions supplied with the furnace
and thermostat. The installation must include a properly
installed filter in the return air system with no by-pass
air. The filter must be inspected frequently and replaced
when necessary.
•Combustion air must be supplied from outside the
structure and located such that dust and gases
from construction activity are not introduced into the
combustion system.
•Provisions must be made to insure that condensate
does not freeze in the furnace or condensate drain lines
during operation and during idle times; for example,
overnight if turned off.
•Before occupying the structure: The filter must be
replaced or cleaned, the duct work must be inspected
and cleaned of any construction debris, and the furnace
must be cleaned and/or repaired if found to be dirty,
damaged, or malfunctioning in any way by a qualified
HVAC technician. The furnace shall be inspected and
approved by applicable local authority even if this
requires redundant inspections.
•Serial numbers for furnaces used during construction
must be submitted in writing (fax and email also
acceptable). This information will be used to track the
long-term affects of the use during construction on
furnaces. Proof of this submittal shall be available for
the final inspection of the furnace prior to occupancy.
•This furnace is designed to operate with return air
temperatures in ranges normally found in occupied
residences, including setbacks. Minimum continuous
return temperature must not be below 60° F (15° C).
Occasionally a temporary return temperature of 55° F
(12° C) is acceptable. However, operation with a return
temperature below 55° F (12° C) is not allowed.
FIRE AND EXPLOSION HAZARD
VENT
Failure to follow these instructions will void the
factory warranty and may significantly reduce
the life or the performance of the furnace, and/
or result in other unsafe conditions. It is the
responsibility of the installing contractor to insure
these provisions are met.
WARNING:
RIGHT SIDE
Operation of Furnace During Construction
SIDE
Left Side.............0 Inches Top Side..............0 Inches
Right Side...........0 Inches Front................†See Note
Vent....................0 Inches Back Side...........0 Inches
†
NOTE: Allow 24 inches minimum clearance for servicing.
Recommended clearance is 36 inches.
Figure 1. Minimum Clearances to
Combustible Materials
COMBUSTION AIR & VENTING REQUIREMENTS
WARNING:
CARBON MONOXIDE POISONING HAZARD
Failure to follow the steps outlined below for
each appliance connected to the venting system
being placed into operation could result in carbon
monoxide poisoning or death.
The following steps shall be followed with each
individual appliance connected to the venting
system being placed in operation, while all other
appliances connected to the venting system are
not in operation:
1.Seal any unused openings in the venting system.
2.Inspect the venting system for proper size and
horizontal pitch, as required in the National Fuel
Gas Code, ANSI Z223.1/NFPA 54 or the CSA B149.1,
Natural Gas and Propane Installation Codes and
these instructions. Determine that there is no
blockage or restriction, leakage, corrosion and
other deficiencies which could cause an unsafe
condition.
3.As far as practical, close all building doors and
windows and all doors between the space in which
the appliance(s) connected to the venting system
are located and other spaces of the building.
4.Close fireplace dampers.
5.Turn on clothes dryers and any appliance not
connected to the venting system. Turn on any
exhaust fans, such as range hoods and bathroom
exhausts, so they are operating at maximum
speed. Do not operate a summer exhaust fan.
6.Follow the lighting instructions. Place the
appliance being inspected into operation.
Adjust the thermostat so appliance is operating
continuously.
7.Test for spillage from draft hood equipped
appliances at the draft hood relief opening after 5
minutes of main burner operation. Use the flame
of a match or candle.
8.If improper venting is observed during any of the
above tests, the venting system must be corrected
in accordance with the National Fuel Gas Code,
ANSI Z223.1/NFPA 54 and/or CSA B149.1, Natural
Gas and Propane Installation Codes.
9.After it has been determined that each appliance
connected to the venting system properly vents
when tested as outlined above, return doors,
windows, exhaust fans, fireplace dampers and
any other gas-fired burning appliance to their
previous conditions of use.
AVERTISSEMENT:
RISQUE D’EMPOISONNEMENT AU
MONOXYDE DE CARBONED
Le non-respect des consignes suivantes portant
sur chacun des appareils raccordés au système
d’évacuation mis en service pourrait entraîner
l’empoisennement au monoxyde de carbone ou
la mort. Les consignes suivantes doivent être
observées pour chaque appareil raccordé au système
d’évacuation mis en service si les autres appareils
raccordés au système ne sont pas en service:
1. Sceller toute ouverture non utilisée de la systéme
d’évacuation;
2. S’assurer que la systéme d’évacuation présente
des dimensions et une pente horizontale conformes
à la norme ANSI Z223.1/NFPA 54, intitulée National
Fuel Gas Code ou aux codes d’installation
CSA-B149.1, ainsi qu’aux présentes instructions.
S’assurer que la systéme d’évacuation n’est
pas bloquée, restreinte, corrodée, qu’elle ne fuit
pas et qu’elle ne présente aucun autre défaut
potentiellement dangereux;
3. Dans la mesure du possible, fermer toutes les
portes et fenêtres du bâtiment, et toutes les portes
entre la pièce où se trouve l’appareil raccordé à
la systéme d’évacuation et les autres pièces du
bâtiment.
4. Fermer les registres des foyers;
5. Mettre en service les sécheuses et tout autre
appareil qui n’est pas raccordé à la systéme
d’évacuation. Faire fonctionner à régime maximal
tout ventilateur d’évacuation, tel que les hottes de
cuisinière et les ventilateurs de salles de bains.
Ne pas mettre en service les ventilateurs d’été.
6. Respecter les instructions d’allumage. Mettre en
service l’appareil à l’essai. Régler le thermostat
de manière à ce que l’appareil fonctionne sans
interruption;
7. Vérifier s’il y a débordement à l’orifice d’évacuation
du coupe tirage des appareils dotés d’un coupe
tirage 5 minutes après l’allumage du brûleur
principal. Utiliser la flamme d’une allumette ou
d’une chandelle.
8. Si l’on constate, au cours de l’un des essais qui
précèdent, que l’évacuation est déficiente, corriger
le système d’évacuation conformément à la norm
ANSI Z223.1/NFPA 54, National Fuel Gas Code, et
(ou) aux codes d’installation CSA B149.1.
9. Après avoir déterminé que tous les appareils
raccordés à la systéme d’évacuation évacuent
correctement tel que prescrit ci-dessus, rouvrir les
portes et les fenêtres et remettre les ventilateurs
d’évacuation, les registres de foyers et tout
autre appareil fonctionnant au gaz à leur état de
fonctionnement initial.
7
IMPORTANT INFORMATION
• This furnace must be vented in compliance with
the current revision of the National Fuel Gas Code
(ANSI-Z223.1/NFPA54). Instructions for determining
the adequacy of an installation can be found in the
current revision of the NFGC (ANSI Z223.1 / NFPA54).
Consult local codes for special requirements. These
requirements are for US installations as found in
the NFGC.
• Furnace installation using methods other than those
described in the following sections must comply
with the National Fuel Gas Code (NFGC) and all
applicable local codes.
• Requirements in Canada (B149.1) are structured
differently. In Canada, venting shall conform to the
requirements of the current (CAN/CGA B149.1 or .2)
installation codes. Consult local codes for special
requirements.
• Provisions must be made during the installation
of this furnace that provide an adequate supply of
air for combustion. The combustion air from the
outside needs to be clear of chemicals that can
cause corrosion. The inlet pipe should not be placed
near corrosive chemicals such as those listed on
page 5.
WARNING:
Upon completion of the furnace installation,
carefully inspect the entire flue system both
inside and outside the furnace to assure it is
properly sealed. Leaks in the flue system can
result in serious personal injury or death due
to exposure of flue products, including carbon
monoxide.
WARNING:
This furnace must not be vented with other
appliances, even if that appliance is of the
condensing type. Common venting can result
in severe corrosion of other appliances or their
venting and can allow combustion gases to
escape through such appliances or vents. Do
not vent the furnace to a fireplace chimney or
building chase.
This condensing furnace is certified for installation either as
a Direct Vent (2-pipe) or Conventional (1-pipe) appliance.
Direct Vent appliances draw combustion air from the
outdoors and vent combustion products back outside.
Installation with air taken from around the furnace is often
referred to as Conventional installation - i.e. only the vent
(exhaust) pipe is provided.
8
Another important consideration when selecting one or
two pipe installation is the quality of the indoor air which
can sometimes be contaminated with various household
chemicals . These chemicals can cause severe corrosion
in the furnace combustion system. A 2-pipe installation
has the additional advantage that it isolates the system
from the effects of negative pressure in the house.
CAUTION:
Exhaust fans, clothes dryers, fireplaces and
other appliances that force air from the house
to the outdoors can create a negative pressure
inside the house, resulting in improper furnace
operation or unsafe conditions such as flame roll
out. It is imperative that sufficient air exchange
with the outdoors is provided to prevent
depressurization. Additional information about
how to test for negative pressure problems can
be found in the National Fuel Gas Code.
Air openings on top of the furnace, in closet doors or
through walls must never be restricted. If the furnace is
operated without adequate air for combustion, the flame
roll-out switch will open, turning off the gas supply to the
burners. This safety device is a manually reset switch.
DO NOT install jumper wires across these switches
to defeat their function or reset a switch without
identifying and correcting the fault condition. If a
switch must be replaced, use only the correct sized part
specified in the Replacement Parts List provided online.
Direct Vent Furnaces
Direct Vent (2-pipe) furnaces draw combustion air directly
from the outdoors and then vent the combustion products
back outside, isolating the entire system from the indoor
space. It is important to make sure that the whole system
is sealed and clearances to combustibles are maintained
regardless of the installation being in a confined or
unconfined space.
Conventional Vent Systems - Confined
Spaces
A confined space is an area with volume less than 50
cubic feet per 1,000 Btuh of the combined input rates of
all appliances drawing combustion air from that space.
Furnace closets, small equipment rooms and garages are
confined spaces. Furnaces installed in a confined space
which supply heated air to areas outside the space must
draw return air from outside the space and must have the
return air ducts tightly sealed to the furnace. Ducts must
have cross - sectional area at least as large as the free area
of their respective openings to the furnace space. Attics
or crawl spaces must connect freely with the outdoors if
they are the source of air for combustion and ventilation.
The required sizing of these openings is determined by
whether inside or outside air is used to support combustion,
the method by which the air is brought to the space, and
by the total input rate of all appliances in the space. In
all cases, the minimum dimension of any combustion air
opening is 3 inches.
Figure 3
Vent or
Chimney
Ventilation Louvers
(each end of attic)
Air From Inside
Outlet
Air
Furnace
Total Input Rating
(Btuh)
40,000
60,000
80,000
100,000
120,000
140,000
160,000
---
---
Ventilation Louvers For
Unheated Crawl Space
Figure 3. Combustion Air Drawn from a Crawl
Space or Vented Attic
Figure
Ventilation Louvers
at each end of attic
4
Vent or
Chimney
Vent or
Chimney
Openings must start at
no more than 12 inches
from the top and bottom
of the enclosure.
Inlet Air
Alternate
Air Inlet
Figure 2
NOTES:
Each opening must be
at least 100 sq. in. or
1 sq. in. per 1,000 Btuh
of total input rating,
whichever is greater.
NOTE: Air openings shall
each have a free area of
not less than one square
inch per 4,000 Btuh of the
total input rating of all
equipment in the enclosure.
Water
Heater
---
Example:
If the combined input rate of all appliances is less
than or equal to 100,000 Btuh, each opening must
have a free area of at least 100 square inches. If the
combined input rate of all appliances is 120,000 Btuh,
each opening must have a free area of at least 120
square inches.
---
If combustion air is taken from the heated space, the two
openings must each have a free area of at least one square
inch per 1,000 Btuh of total input of all appliances in the
confined space, but not less than 100 square inches of
free area. See example and Figure 2.
Attic
Insulation
12” Max.
See
Notes
Water
Heater
Water
Heater
Furnace
Furnace
See
Notes
Minimum Free Area
(Each Opening)
100 sq. In
100 sq. In
100 sq. In
100 sq. In
120 sq. In
140 sq. In
160 sq. In
Ducts must
extend above
attic insulation.
Air Duct must be
at least 1 sq. in.
per 4,000 Btuh of
total input rating.
12" Max
12” Max.
Round Duct
Diameter
12 inches
12 inches
12 inches
12 inches
13 inches
14 inches
15 inches
Figure 2. Combustion Air Drawn from Inside
Outdoor Air from a Crawl Space or Vented
Attic
When the openings can freely exchange air with the
outdoors, each opening shall have a minimum free area
of 1 square inch per 4,000 Btuh of total appliance input.
The openings shall exchange directly, or by ducts, with
the outdoor spaces (crawl or attic) that freely exchange
with the outdoors. See Figure 3.
Outdoor Air Using Vertical Ducts
Air Duct must be
at least 1 sq. in.
per 4,000 Btuh of
total input rating.
If combustion air is taken from outdoors through vertical
ducts, the openings and ducts must have a minimum free
area of one square inch per 4,000 Btuh of total appliance
input. See Figure 4.
Total Input Rating
(Btuh)
40,000
60,000
80,000
100,000
120,000
140,000
160,000
Minimum Free Area
(Each Opening)
10 sq. In
15 sq. In
20 sq. In
25 sq. In
30 sq. In
35 sq. In
40 sq. In
Round Duct
Diameter
4 inches
5 inches
5 inches
6 inches
6 inches
7 inches
8 inches
Figure 4. Combustion Air Drawn from Outside
Through Vertical Ducts
Outdoor Air Using Horizontal Ducts
If combustion air is taken from outdoors through horizontal
ducts, the openings and ducts must have a minimum free
area of one square inch per 2,000 Btuh of total appliance
input. Ducts must have cross - sectional area at least as
large as the free area of their respective openings to the
furnace space. See Figure 5, (page 10).
Air Directly Through an Exterior Wall
If combustion air is provided directly through an exterior
wall, the two openings must each have free area of at
least one square inch per 4,000 Btuh of total appliance
input. See Figure 6, (page 10).
9
Figure 5
Alternate Method of Providing Air from Outside:
Vent or
Chimney
Air Duct
Water
Heater
Furnace
Air Ducts must be
at least 1 sq. in.
per 2,000 Btuh of
total input rating.
Air Duct
THE FOLLOWING CONDITIONS MUST BE MET:
Total Input Rating
(Btuh)
Minimum Free Area
(Each Opening)
Round Duct
Diameter
40,000
60,000
80,000
100,000
120,000
140,000
160,000
20 sq. In
30 sq. In
40 sq. In
50 sq. In
60 sq. In
70 sq. In
80 sq. In
5 inches
6 inches
7 inches
8 inches
9 inches
10 inches
10 inches
Figure 5. Combustion Air Drawn from Outside
Through Horizontal Ducts
Figure 6
Vent or
Chimney
See
Note
---
12"
Max
NOTE: Each opening to outside
must be at least 1 sq. in. per
4,000 Btuh of total input rating.
Water
Heater
Furnace
See
Note
12" Max.
---
1. The opening must start within 12” of the top of the
structure and connect with the out of doors through
vertical or horizontal ducts or be ducted to a crawl or
attic space that connects with the out of doors.
2. The opening must have a minimum free area of 1 in2.
per 3,000 Btu per hour of the total input rating of all
equipment located in the enclosure.
3. The free area must not be less than the sum of all the
areas of the vent connectors in the enclosure.
Conventional Vent Systems - Unconfined
Spaces
An unconfined space is an area including all rooms not
separated by doors with a volume greater than 50 cubic
feet per 1,000 Btuh of the combined input rates of all
appliances which draw combustion air from that space.
In general, a furnace installed in an unconfined space will
not require outside air for combustion. However, in homes
built for energy efficiency (low air change rates), it may
be necessary to provide outside air to ensure adequate
combustion and venting, even though the furnace is located
in an unconfined space. See example below.
Category IV Venting
Total Input Rating
(Btuh)
Minimum Free Area
(Each Opening)
Round Duct
Diameter
40,000
60,000
80,000
100,000
120,000
140,000
160,000
10 sq. In
15 sq. In
20 sq. In
25 sq. In
30 sq. In
35 sq. In
40 sq. In
4 inches
5 inches
5 inches
6 inches
6 inches
7 inches
8 inches
Figure 6. Combustion Air Drawn from Outside
Through an Exterior Wall
Example:
A space with a water heater rated at 45,000 Btuh
input and a furnace rated at 75,000 Btuh requires a
volume of 6,000 cubic feet [50 x (45 + 75) = 6,000] to
be considered unconfined. If the space has an 8 foot
ceiling, the floor area of the space must be 750 sq. ft.
(6,000 / 8 = 750).
10
If acceptable under local Codes, it is permitted to provide
outside air using one opening (See NFGC). Generally,
confined spaces must have 2 openings in the space for
combustion air. One opening must be within 12 inches of
the ceiling, and the other must be within 12 inches of the
floor. However, an alternative method recently adopted by
the NFGC uses one opening within 12 inches of the top
of the space. This method may be used if it is acceptable
to the local codes.
WARNING:
Upon completion of the furnace installation,
carefully inspect the entire flue system both
inside and outside the furnace to assure it is
properly sealed. Leaks in the flue system can
result in serious personal injury or death due
to exposure of flue products, including carbon
monoxide.
This furnace is classified as a Category IV appliance,
which requires special venting materials and installation
procedures. This section specifies installation requirements
for Conventional (1-pipe) and Direct Vent (2-pipe) piping.
For 1- pipe installations, install vent piping as described in
this section and provide air for combustion and ventilation
according to pages 7 - 10. The length of vent and
combustion air piping for either type of installation are
shown in in Table 1, (page 11).
Category IV appliances operate with positive vent pressure
and therefore require vent systems which are thoroughly
sealed. They also produce liquid condensate, which is
slightly acidic and can cause severe corrosion of ordinary
venting materials. Furnace operation can be adversely
affected by restrictive vent and combustion air piping.
The inducer assembly on this furnace can be rotated to
vent the flue products out of the left or right side of the
furnace. This increases the flexibility of which direction
the vent pipe can exit the furnace.
Vent Pipe Material
Vent and combustion air pipe and fittings must be one of
the following materials in the list and must conform to the
indicated ANSI/ASTM standards. Cement must conform
to ASTM Standard D2564 for PVC and Standard D2235
for ABS. PVC primer must meet standard ASTM F656.
When joining PVC piping to ABS, use PVC solvent cement
(See procedure specified in ASTM Standard D3138).
In Canada, all plastic vent pipes and fittings including
any cement, cleaners, or primers must be certified as a
system to ULC S636. However this requirement does not
apply to the finish flanges or piping internal to the furnace.
Materials
Standards
SCHEDULE 40PVC................................ D1785
PVC-DWV............................................... D2665
SDR-21 & SDR-26.................................. D2241
ABS-DWV............................................... D2661
SCHEDULE 40 ABS............................... F628
FOAM / CELLULAR CORE PVC............ F891
FURNACE
MODELS
(BTU)
60,000
80,000
100,000
120,000
FURNACE
INSTALLATION
Vent Pipe Length & Diameter
In order for the furnace to operate properly, the combustion
air and vent piping must not be excessively restrictive.
•The venting system should be designed to have the
minimum number of elbows or turns.
•Transition to the final vent diameter should be done as
close to the furnace outlet as practical.
•Always use the same size or a larger pipe for combustion
air that is used for the exhaust vent.
Table 1 indicates the maximum allowable pipe length for
a furnace of known input rate, when installed with piping
of selected diameter and number of elbows. To use the
table, the furnace input rate, the centerline length and the
number of elbows on each pipe must be known.
When estimating the length of vent runs, consideration
must be made to the effect of elbows and other fittings.
This is conveniently handled using the idea of equivalent
length. This means the fittings are assigned a linear length
that accounts for the pressure drop they will cause. For
example: a 2” diameter, long radius elbow is worth the
equivalent of 2.5 feet of linear run. A 90 degree tee is
worth 7 ft.
The equivalent lengths of tees and various elbows are
listed in Table 1. Measure the linear length of the vent run
and then add in the equivalent length of each fitting. The
total length, including the equivalent fitting lengths, must
be less than the maximum length specified in the table.
Table(FT.)
1
SINGLE VENT PIPE LENGTH
with 1 long radius elbow*
DUAL VENT PIPE LENGTH (ft.)
with 1 long radius elbow on each pipe*
OUTLET
2” Diameter
OUTLET
3” Diameter
INLET/OUTLET
2” Diameter
INLET/OUTLET
3” Diameter
Upflow
50
80
50
80
Horizontal
40
80
40
80
Upflow
60
90
60
90
Horizontal
50
90
50
90
90
Upflow
50
90
50
Horizontal
40
90
40
90
Upflow
N/A
90
N/A
90
Horizontal
N/A
70
N/A
70
*NOTES:
1 Subtract 2.5 ft. for each additional 2 inch long radius elbow, 5 ft. for each additional 2 inch short radius elbow, 3.5 ft. for each additional 3
inch long radius elbow, and 7 ft. for each additional 3 inch short radius elbow. Two 45° elbows are equivalent to one 90° elbow.
2. Subtract 5ft for each 2” tee and 8ft for each 3” tee.
3. This table applies for elevations from sea level to 2,000 ft. For higher elevations, decrease pipe lengths by 8% per 1,000 ft of altitude.
4. The minimum length for 2” or 3” diameter vent pipe is 5 ft.
Table 1. Vent Pipe Lengths
11
Vent Pipe Installation
CAUTION:
Combustion air must not be drawn from a
corrosive atmosphere.
This furnace has been certified for installation with zero
clearance between vent piping and combustible surfaces.
However, it is good practice to allow space for convenience
in installation and service.
•The quality of outdoor air must be considered. Make sure
the combustion air intake is not located near a source
of solvent fumes or other chemicals which can cause
corrosion of the furnace combustion system. (See list
of substances on page 5).
•Route piping as direct as possible between the furnace
and the outdoors. Horizontal piping from inducer to
the flue pipe must be sloped 1/4” per foot to ensure
condensate flows towards the drain tee or PVC trap.
Longer vent runs require larger pipe diameters. Refer
to the Inducer & Venting Options section on page 17
for additional information.
•If a Direct Vent (2-pipe) system is used, the combustion
air intake and the vent exhaust must be located in the
same atmospheric pressure zone. This means both
pipes must exit the building through the same portion
of exterior wall or roof as shown in Figure 7, Figure 8,
(page 12), Figure 9, (page 13), & Figure 10, (page
13).
•Piping must be mechanically supported so that its weight
does not bear on the furnace. Pipe supports must be
installed a minimum of every 5 feet along the vent run to
ensure no displacement after installation. Supports may
be at shorter intervals if necessary to ensure that there
are no sagging sections that can trap condensate. It is
recommended to install couplings along the vent pipe,
on either side of the exterior wall as shown in Figure
28, (page 38). These couplings may be required by
local code.
•If breakable connections are required in the combustion
air inlet pipe (if present) and exhaust vent piping, then
straight neoprene couplings for 2” or 3” piping with
hose clamps can be used. These couplings can be
ordered through your local furnace distributor. To install
a coupling:
1. Slide the rubber coupling over the end of the pipe that
is attached to the furnace and secure it with one of
the hose clamps.
2. Slide the other end of the rubber coupling onto the
other pipe from the vent.
3. Secure the coupling with the second hose clamp,
ensuring that the connection is tight and leak free.
Outdoor Terminations - Horizontal Venting
•Vent and combustion air intake terminations shall be
installed as depicted in Figure 7 & Figure 8 and in
accordance with these instructions:
•Vent termination clearances must be consistent with the
NFGC, ANSI 2223.1/NFPA 54 and/or the CSA B149.1,
Natural Gas and Propane Installation Code. Table 11
(page 35) lists the necessary distances from the vent
termination to windows and building air intakes.
•Vent and combustion air intake terminations must
be located to ensure proper furnace operation and
conformance to applicable codes. A vent terminal
must be located at least 3 feet above any forced air
inlet located within 10 feet. This does not apply to the
combustion air inlet of a direct vent (two pipe) appliance.
In Canada, CSA B149.1, takes precedence over these
instructions. See Table 11, (page 35).
•All minimum clearances must be maintained to protect
building materials from degradation by flue gases as
shown in Figure 8.
Figure 7
in.
18” M
ax.
36” M
t
st ven
Exhauon C
opti
te
faceplarews
c
ng kit
Mountito wall with s
)
d
secure (both pipes
t
st ven
Exhauon A
opti
lbow
90° E
t
st ven
Exhauon B
ti
op
.
8” Minx.
a
36” M ions)
sit
(all po
ustion
Combinlet
air
um
maxim vel
in. to
le
12” mcted snow
expe oth pipes)
(b
Figure 7. Inlet & Exhaust Pipe Clearances
Figure 8
Dir
ec
50 term t ven
,00 ina t
or 0 Bt l
les uh
s
Me
dra chan
ter ft venical
min t
al
9 in
.
No
te
l
ica
an
ch nt
Meaft veal
dr min
ter
4f
t
2
Mechanical draft
vent terminal
4 ft
No
te
12
in.
2
NOTES:
1. All dimensions shown are
minimum requirements.
2. Exterior vent terminations must
be located at least 12” above the
maximum expected snow level.
n.
2i
1
te
No
2
ss
Lean
th ft.
10
Forced air inlet
Direct vent
terminal - more
than 50,000 Btuh
Figure 8. Vent Locations
12
.
3 ft
•For optimal performance, vent the furnace through a wall
that experiences the least exposure to winter winds.
•The vent termination shall be located at least 3 ft.
horizontally from any electric meter, gas meter, regulator
and any relief equipment. These distances apply ONLY
to U.S. installations. In Canada, CSA B149.1, takes
precedence over these instructions.
•Do not install the vent terminal such that exhaust is
directed into window wells, stairwells, under decks
or into alcoves or similar recessed areas, and do not
terminate above any public walkways.
•If venting horizontally, a side wall vent kit is available
according to the pipe diameter size of the installation. For
2 inch pipe use side wall vent kit #904617, and for 3 inch
pipe use kit #904347. Please follow the instructions
provided with the kit.
•Concentric vent termination kits are available for use
with these furnaces. For 2 Inch pipe use kit #904952
and for 3 inch pipe use kit # 904953. Please follow the
instructions provided with the kit.
•When the vent pipe must exit an exterior wall close to
the grade or expected snow level where it is not possible
to obtain clearances shown in Figure 7, a riser may
be used as shown in Figure 9. Insulation is required
to prevent freezing of this section of pipe. See Vent
Freezing Protection Section.
Figure 9
19" Max.
(See Note)
12" Above
Maximum
Expected
Snow Level
Support
1/2"
Armaflex
Insulation or
Equivalent
(if required)
Outside
Wall
NOTE: Vent Configuration to Provide
12" Minimum height above Snow Level.
Figure 9. Alternate Horizontal Vent Installation
Figure 10 Plumbing Vent Roof Boot
Termination spacing requirements from the roof and from
each other are shown in Figure 9. The roof penetration
must be properly flashed and waterproofed with a plumbing
roof boot or equivalent flashing. Vent and combustion air
piping may be installed in an existing chimney which is
not in use provided that:
•Both the exhaust vent and air intake run the length of
the chimney.
•The top of the chimney is sealed and weatherproofed.
•The termination clearances shown in Figure 10 are
maintained.
•No other gas fired or fuel-burning equipment is vented
through the chimney.
Vent Freezing Protection
CAUTION:
When the vent pipe is exposed to temperatures
below freezing (i.e., when it passes through
unheated spaces, chimneys, etc.) the pipe must
be insulated with 1/2 inch thick sponge rubber
insulation, Armaflex-type insulation or equivalent.
Insulating pipe is important to avoid condensate
icing.
•Table 2, (page 14) lists the maximum length of flue
pipe that can travel through an unconditioned space or
an exterior space. The total vent length must not exceed
the lengths noted in Table 1, (page 11). For Canadian
installations, please refer to the Canadian Installation
Code (CAN/CGA-B149.1 or 2) and/or local codes.
•For extremely cold climates or for conditions of short
furnace cycles (i.e. set back thermostat conditions)
the last 18 inches of vent pipe can be reduced. It is
acceptable to reduce from 3” to 2-1/2”, 3” to 2”, or 2” to
1-1/2” if the total vent length is at least 15 feet in length,
and the vent length is within the parameters specified
in Table 1. The restriction should be counted as 3
equivalent feet. Smaller vent pipes are less susceptible
to freezing, but must not be excessively restrictive. The
length of the 2 inch pipe must not be longer than 18
inches.
•To prevent debris or creatures from entering the
combustion system, a protective screen may be installed
over the combustion air intake opening. The screens
hole size must be large enough to prevent air restriction.
Exhaust Vent
12” Above Maximum
Expected Snow Level
(Both pipes)
(Both Pipes)
Combustion Air
Elbows on the combustion air
inlet must be positioned pointing
away from the exhaust vent.
Outdoor Terminations - Vertical Venting
in.
8" M ax.
M
36"
Figure 10. Vertical Vent Termination
13
Table 2
Winter Design
Temperature
Maximum Flue Pipe Length (FEET)
in Unconditioned & Exterior Spaces
Without Insulation
With Insulation*
20
45
70
0
20
70
-20
10
60
*NOTE: Insulation thickness greater than 3/8 inch, based on an
R value of 3.5 (ft x F x hr) / (BTU x in.)
Table 2. Vent Protection
Existing Installations
When an existing furnace is removed from a vent system
serving other appliances, the existing vent system may
not be sized properly to vent the remaining appliances
(For example: water heater). An improperly sized venting
system can result in the formation of condensate, leakage,
or spillage. The existing vent system should be checked
to make sure it is in compliance with the NFGC and must
be brought into compliance before installing the furnace.
NOTE: If replacing an existing furnace, it is possible you
will encounter an existing plastic venting system that is
subject to a Consumer Product Safety Commission recall.
The pipes involved in the recall are High Temperature
Plastic Vent (HTPV). If your venting system contains
these pipes DO NOT reuse this venting system! This
recall does not apply to other plastic vent pipes, such
as white PVC or CPVC. Check for details on the CPSC
website or call their toll-free number (800) 758-3688.
Condensate Disposal
The method for disposing of condensate varies according
to local codes. Consult your local code or authority having
jurisdiction.
Each of the condensate drain lines must be J-trapped
using field supplied parts. After the condensate lines are
J-trapped, they may be combined together into a single
run to the drain. The drain lines must be routed downward
to ensure proper drainage from furnace.
Neutralizer kit P/N 902377 is available for use with this
furnace. Please follow the instructions provided with
the kit.
For Installations where there is limited clearance for the
J-Trap (such as an attic where it may be installed between
ceiling joists), either side of the J-Trap can be shortened
to a minimum of 3 Inches. Figure 11, (page 16).
14
CIRCULATING AIR REQUIREMENTS
WARNING:
Do not allow combustion products to enter the
circulating air supply. Failure to prevent the
circulation of combustion products into the
living space can create potentially hazardous
conditions including carbon monoxide poisoning
that could result in personal injury or death.
All return ductwork must be secured to the
furnace with sheet metal screws. For installations
in confined spaces, all return ductwork must be
adequately sealed. When return air is provided
through the bottom of the furnace, the joint
between the furnace and the return air plenum
must be air tight.
The surface that the furnace is mounted on must
provide sound physical support of the furnace
with no gaps, cracks or sagging between the
furnace and the floor or platform.
Return air and circulating air ductwork must
not be connected to any other heat producing
device such as a fireplace insert, stove, etc. This
may result in fire, explosion, carbon monoxide
poisoning, personal injury, or property damage.
Plenums & Air Ducts
•Plenums and air ducts must be installed in accordance
with the Standard for the Installation of Air Conditioning
and Ventilating Systems (NFPA No. 90A) or the
Standard for the Installation of Warm Air Heating and
Air Conditioning Systems (NFPA No. 90B).
•Table 7, (page 31) lists the High and Low target CFMs
for each maximum input rate and temperature rise. If the
maximum airflow is greater than 1,600 cfm, two returns
are recommended. NOTE: The motor speed of *MQ
furnaces cannot be changed manually by resetting the
dipswitches on the motor control board.
•It is recommended that the outlet duct contain a
removable access panel. The opening should be
accessible when the furnace is installed in service and
shall be of a size that smoke or reflected light may be
observed inside the casing to indicate the presence of
leaks in the heat exchanger. The cover for the opening
shall be attached in such a way as to prevent leaks.
•If outside air is used as return air to the furnace for
ventilation or to improve indoor air quality, the system
must be designed so that the return air is not less than
60° F (15° C) during operation. If a combination of indoor
and outdoor air is used, the ducts and damper system
must be designed so that the return air supply to the
furnace is equal to the return air supply under normal,
indoor return air applications.
•When a cooling system is installed which uses the
furnace blower to provide airflow over the indoor coil,
the coil must be installed downstream (on the outlet
side) of the furnace or in parallel with the furnace.
•If a cooling system is installed in parallel with the
furnace, a damper must be installed to prevent chilled air
from entering the furnace and condensing on the heat
exchanger. If a manually operated damper is installed,
it must be designed so that operation of the furnace is
prevented when the damper is in the cooling position
and operation of the cooling system is prevented when
the damper is in the heating position.
•It is good practice to seal all connections and joints
with industrial grade sealing tape or liquid sealant.
Requirements for sealing ductwork vary from region
to region. Consult with local codes for requirements
specific to your area.
•Bottom Return Installations: If using the bottom of
the furnace for return air, the bottom panel (Figure 22)
must be removed from the bottom of the furnace. See
page 16 for removal instructions. Position the furnace
over the return air duct and secure together with sheet
metal screws. Make sure the screws penetrate the duct
and furnace casing.
Return Air Connections
Supply Air Connections
•In applications where the supply ducts carry heated
air to areas outside the space where the furnace is
installed, the return air must be delivered to the furnace
by duct(s) secured to the furnace casing, running full
size and without interruption. Do not use the back of
the furnace for return air.
•Position the furnace with the return air ductwork
ensuring even alignment of furnace (or coil casing) air
opening and return air duct. NOTE: The ductwork must
have an opening equal to that of the return air opening
of the furnace (or coil casing). See Figure 22, (page
31) for return air opening size.
Upflow & Horizontal Furnaces
•The return air ductwork may be connected to the left
side, right side, or bottom of the furnace. NOTE: If using
the left or right side of the furnace for return air, the
bottom panel (Figure 22) must not be removed from the
bottom of the furnace.
WARNING:
The bottom panel of the furnace must be in place
when the furnace is installed with side return air
ducts. Removal of all or part of the base could
cause circulation of combustible products into
the living space and create potentially hazardous
conditions, including carbon monoxide poisoning
that could result in personal injury or death.
•Side Return Installations: To attach the return air duct
to the left or right side of the furnace, punch out the
4 knockouts from the side of the furnace (Figure 22,
(page 31)). Using sharp metal cutters, cut an opening
between all 4 knockouts to expose the blower assembly.
Position the return air duct over the opening and secure
to the side with sheet metal screws.
Downflow Furnaces
•To attach the return air duct to the downflow furnace,
bend the flanges on the furnace upward 90° with wide
duct pliers. See Figure 22, (page 31) for furnace
flange locations. NOTE: If system installation includes
AC coil casing, bend the flanges on the coil casing
upward 90° before attaching the return air duct.
•Secure the return air ductwork to the furnace or coil
casing (if installed) with sheet metal screws. Make sure
the screws penetrate the sheet metal casing and flanges.
•The supply air must be delivered to the heated space
by duct(s) secured to the furnace or coil box casing,
running full size and without interruption.
•To attach the supply air duct to upflow & horizontal
furnaces, bend the flanges on the furnace upward 90°
with wide duct pliers. See Figure 22, (page 31) for
furnace flange locations. NOTE: If system installation
includes AC coil casing, bend the flanges on the coil
casing upward 90° before attaching the supply air duct.
•Position the supply air ductwork onto the furnace
ensuring even alignment of furnace air opening and
supply air duct. NOTE: The ductwork must have an
opening equal to that of the supply air opening of the
furnace. See Figure 22 for supply air opening size.
Acoustical Treatments
Damping ducts, flexible vibration isolators, or pleated
media-style filters on the return air inlet of the furnace
may be used to reduce the transmission of equipment
noise eminating from the furnace. These treatments can
produce a quieter installation, particularly in the heated
space. However, they can increase the pressure drop in
the duct system. Care must be taken to maintain the proper
maximum pressure rise across the furnace, temperature
rise and flow rate. This may mean increasing the duct
size and/or reducing the blower speed. These treatments
must be constructed and installed in accordance with
NFPA and SMACNA construction standards. Consult
with local codes for special requirements. For best sound
performance, be sure to install all the needed gaskets and
grommets around penetrations into the furnace, such as
for electrical wiring
15
FURNACE INSTALLATION
*MQ series gas furnaces may be installed in the upflow
or horizontal right or left positions with either right, left,
or upflow return air.
General Requirements
•The furnace must be leveled at installation and attached
to a properly installed duct system. See Table 1, (page
11) for the required clearances needed to move the
furnace to its installation point (hallways, doorways,
stairs, etc).
•The furnace must be installed so that all electrical
components are protected from water.
•The furnace must be installed upstream from a
refrigeration system. (If applicable)
•The cabinet plug must always be used to close the hole
in the side of the furnace when rotating the inducer.
•The furnace requires special venting materials and
installation procedures. See pages 10 -14 for
venting guidelines and specifications.
Upflow Installation
If the furnace will be suspended from the ceiling, assemble
a support frame (Figure 12) using slotted iron channel
and full thread rod. Fasten the frame together with nuts,
washers, and lockwashers. Secure the support frame to the
rafters with lag bolts. The furnace can also be suspended
using steel straps around each end of the furnace. The
straps should be attached to the furnace with sheet metal
screws and to the rafters with bolts.
It is recommended for further reduction of fire hazard
that cement board or sheet metal be placed between the
furnace and the combustible floor and extend 12 inches
beyond the front of the door and top of the furnace.
Figure 11
Flue pipe vented
to outside
Wood or
non-combustible
platform
Coil Plenum
Combustion Air
Condensate
Drain Lines
WARNING:
J-Trap
Height
3” Min.
The furnace must not be installed directly on
carpeting, tile, or any combustible material other
than wood flooring.
*MQ series gas furnaces are shipped with the bottom
panel installed as shown in Figure 23, (page 33). If
the furnace is installed with side return air, the bottom
panel must not be removed. If the furnace is installed with
bottom return air, the bottom panel must be removed. See
Bottom Panel Removal on page 16.
Figure 11. Horizontal installation on a Platform
Figure 12
Horizontal Installation
WARNING:
The *MQ series gas furnace must not be installed
directly on carpeting, tile, or any combustible
material other than wood flooring.
The *MQ series gas furnace can be installed horizontally
in an attic, basement, crawl space or alcove (Figure 11).
It can also be suspended from a ceiling in a basement
or utility room in either a right to left airflow or left to right
airflow as shown in Figure 12.
*MQ series furnaces are shipped with the bottom panel
installed. If furnace is installed horizontally, remove the
bottom panel from the furnace before attaching the duct
system. See Bottom Panel Removal (page 16).
If installing the furnace in an attic, it is required that a drip
pan be placed under the furnace. If the installation is on
a combustible platform (Figure 11), it is recommended
that the drip pan extend at least 12 inches past the top
and front of the furnace.
16
Nuts (x2)
Threaded
Rod
Washer
and
Lockwasher
Lag
Bolt
Nuts (x2)
Figure 12. *MQ Suspended Horizontally
Bottom Panel Removal
The steps listed below describe how to remove the bottom
panel from the furnace. See Figure 13, (page 17).
1. Remove the door (1) from the blower compartment.
2. Disconnect the wiring harness (2) from the furnace
blower deck.
3. Remove two screws (3) securing the blower assembly
(4) to the furnace.
4. Carefully pull the blower assembly (4) out thru the
front of the furnace.
5. Remove all screws (5) securing bottom panel (6) to
bottom of furnace and front brace (7).
6. Lift up and slide bottom panel (6) out through front of
furnace.
7. Reinstall the blower assembly (4) in reverse order.
1
To increase installation flexibility, the inducer assembly
can be rotated to 2 different positions. Each variation has
slightly different requirements with regard to condensate
disposal and, in some cases, the need to seal the furnace
cabinet.
Figure 13
IMPORTANT NOTE
The Inducer Assembly must never be positioned to
vent downwards on horizontal installs.
2
Before using Table 3, the number of pipes (1-pipe or
2-pipe) connected to the furnace must be known. Find
the proper furnace style (upflow or horizontal) and then
the side that the pipes will exit from the furnace. Finally
select the option that properly matches your installation
type from Figure 26, (page 36) & Figure 27, (page 37).
3
5
4
6
7
Figure 13. Bottom Panel Removal
Alternate Bottom Panel Removal
If the bottom panel cannot be removed using the previous
instructions, the steps below are an alternate method for
removing the bottom panel. See Figure 14.
1. Remove the door (1) from the blower compartment
2. Remove all screws securing the bottom panel (2) to
the front brace (3).
3. Remove two screws (4) securing the furnace cabinet
to the blower deck (5).
4. Remove all screws (6) securing the furnace cabinet
to the bottom panel (2).
5. Remove the screw (7) securing the bottom corner of
the furnace cabinet to the front brace (3).
6. Carefully spread the bottom corner of the furnace
cabinet outwards while sliding the bottom panel (2)
out through the front of the furnace.
7. Reassemble the furnace in reverse order.
NOTE: It is important that Direct Vent (2-pipe) systems
maintain an airtight flow path from the air inlet to the flue
gas outlet. The *MQ furnace is shipped from the factory
with two holes in the cabinet for the flue gas outlet. In
certain configurations, it is necessary to remove and
relocate a plastic cap in the furnace cabinet. If changing
the position of the flue gas outlet, it is required that the
previous hole be closed off with the plastic cap to maintain
air tightness in the furnace. The hole locations for *MQ
series upflow/horizontal furnaces are indicated in Figure
22, (page 31).
Table 3
1 - PIPE INSTALLATIONS
Vent
Upflow
Horizontal Right
Horizontal Left
Right
Option 1
N/A
Option 6
Left
Option 2
Option 5
N/A
2 - PIPE INSTALLATIONS
Vent
Upflow
Horizontal Right
Horizontal Left
Right
Option 3
N/A
Option 8
Left
Option 4
Option 7
N/A
Table 3. Vent & Inducer Blower Options
Inducer Assembly Rotation
Figure 14
WARNING:
4
5
1
Inducer & Venting Options
7
6
Inducer rotation must be completed before
the furnace is connected to gas and electric. If
both utilities have been connected, follow the
shutdown procedures printed on the furnace
label and disconnect the electrical supply.
CAUTION:
2
3
Figure 14. Alternate Removal Method
It is good practice to label all wires prior to
disconnection.Wiring errors can cause improper
and dangerous operation.
17
1. Disconnect both electrical harnesses from the inducer
assembly.
2. Disconnect 2 wires from the inducer assembly limit
switch.
3. Disconnect the pressure switch vacuum tube from the
inducer assembly.
4. Remove 4 screws securing the inducer assembly to
the header box.
5. Rotate the inducer assembly to its new position.
NOTE: Verify the screw holes in the inducer assembly
are aligned with the mounting holes in the header box.
6. Secure the inducer assembly to the header box by
reinstalling the 4 screws.
7. Move the cabinet plug from side of furnace and reinstall
in hole on opposite side of cabinet.
8. Reconnect the electrical harness to the inducer
assembly.
Accessories
The components in Figure 15 & Figure 16, (page 19)
are included in the extra parts bag that is supplied with the
purchase of MQ furnaces. Depending on your particular
installation, some of these components are optional and
may not be used. Please refer to the descriptions and
accompanying figures when installing these items.
Finish Flange
The Finish Flange must be installed to vent the combustion
air pipe through the top of the furnace. NOTE: For proper
installation, it is important that the pipe and screw holes
in the finish flange, gasket, and cabinet are aligned. See
Figure 15.
1. Position flange gasket over hole in the furnace cabinet.
2. Position finish flange on top of the flange gasket with
FRONT lettering nearest to the front of the furnace.
3. Secure flange and gasket to cabinet with three field
supplied sheet metal screws.
Figure 15
FRONT
Rubber Grommets
The 2 1/4” rubber grommet is used to seal the opening
between the furnace cabinet and the 2” PVC vent pipe.
The rubber grommet should be installed in the 3” hole
prior to running the vent pipe out of cabinet. No sealants
are required. See Figure 15.
The 7/8” rubber grommet is used to seal the opening
between the furnace cabinet and the gas pipe. The rubber
grommet should be installed in the 1 5/8” hole prior to
running the gas pipe into the cabinet. No sealants are
required.
The 3/4” rubber grommet is used if venting out the left
side of the cabinet and the drain tube is routed through
the blower deck. Remove the plastic plug from the hole
and install the grommet before routing the drain tube.
PVC Components
IMPORTANT NOTE
Before permanently installing these components, it is
recommended you dry-fit them first to ensure proper
fit and alignment with other vent pipes.
The 2” PVC Tee and Trap shown in Figure 16, (page 19)
are used when the inducer is rotated to vent out thru the
left or right side of the furnace cabinet.
The 1/2” x 3/4” hose barb can be used to route the
condensate drain to the outside of the cabinet. It must
be installed from inside the cabinet with the threaded
end inserted thru the 1 1/16” hole. The condensate drain
should be connected to the barbed end. Attach 1” PVC
drain line to the threaded end.
Typical Orientation
1. Install the PVC Tee vertically on the 2” vent pipe that is
extending out the side of the cabinet. Permanently bond
them together using appropriate primer and cement.
Refer to the typical orientation shown in Figure 16.
2. Install the reducer or PVC trap (if supplied) on the
bottom end of the PVC Tee. Permanently bond them
together using appropriate primer and cement.
3. Install the 1/2” x 1/2” hose barb on the 2” PVC reducer. NOTE: Do not over tighten! Use an adequate amount of
Teflon tape on the threads. Do not use liquid sealants.
4. Verify all connections and joints for tight fit and proper
alignment with other vent pipes.
Alternate Orientation
FRONT lettering must be
located near front
of furnace
Flange
Gasket
Inlet Air
Finish Flange
ø 2 1/4” Rubber
Grommet
ø 3/4” Rubber
Grommet
Figure 15. Rubber Grommets
18
ø 7/8” Rubber
Grommet
1. Install the 2” PVC Tee horizontally on the 2” vent
pipe that is extending out the side of the cabinet.
Permanently bond them together using appropriate
primer and cement. Refer to the alternate orientation
shown in Figure 16.
2. Install the 2” PVC Elbow on the end of the 2” PVC Tee.
Permanently bond them together using appropriate
primer and cement.
3. Install the reducer or PVC trap (if supplied) on the
bottom end of the PVC Tee. Permanently bond them
together using appropriate primer and cement.
Figure 16
4. Install the 1/2” x 1/2” hose barb on the 2” PVC reducer. NOTE: Do not over tighten! Use an adequate amount of
Teflon tape on the threads. Do not use liquid sealants.
5. Verify all connections and joints for tight fit and proper
alignment with other vent pipes.
2” PVC Pipe from
Inline Drain Assembly
(Not Included)
Condensate Drain Lines
2” PVC Tee
1/2” Tubing
(Field Supplied)
PVC Trap
1/2” x 3/4”
Hose Barb
Installation of PVC Components (Typical Orientation)
The placement of the condensate drain lines will depend
on the configuration selected in Table 3, (page 17). The
drain lines can be routed out the left or right side of the
furnace, but must maintain a downward slope to ensure
proper condensate drainage.
2” PVC Pipe from
Inline Drain Assembly
(Not Included)
2” PVC TEE
2” PVC ELBOW
(Field Supplied)
1/2” Tubing
(Field Supplied)
PVC Trap
1/2” x 3/4”
Hose Barb
Installation of PVC Components (Alternate Orientation)
Figure 16. PVC Components
IMPORTANT NOTE
If the furnace is installed in an area where temperatures
fall below freezing, special precautions must be made
for insulating condensate drain lines that drain to the
outdoors. If condensate freezes in the lines, this will
cause improper operation or damage to the furnace. It
is recommended that all drain lines on the outside of
the residence be wrapped with an industry approved
insulation or material allowed by local code.
The J-trap may need to be rotated to the side that matches
your setup in Figure 26, (page 36) & Figure 27, (page
37). To rotate the J-trap, loosen the clamp on the
drain tube, rotate the J-trap to either side, and retighten
the clamp.
THREE GENERAL PRINCIPLES APPLY:
•Each condensate drain line must be separately trapped
using a J-Trap or field supplied loop. After individually
trapping the condensate lines, it is acceptable to
combine the drains.
•There must always be a drain attached to the collector
at the outlet of the secondary heat exchanger.
•There must always be a drain at the lowest point of the
venting system. NOTE: If using a condensate pump, the
furnace drain line must be installed above the pumps
water line.
EXCEPTIONS & CLARIFICATIONS TO THE
GENERAL RULES:
•In some cases, the lowest point in the vent system is
where it connects to the inducer (Options 2 & 4). In this
case one drain at this location is sufficient.
•If the vent exits the furnace horizontally, the vent may
be turned vertically with a tee. The drip leg formed by
the tee must include a drain (Options 1, 2, 3, & 4).
•In certain cases, it is permitted to drain the inducer back
into the top drain of the collector (Options 1, 3, 5, & 7).
More importantly, make sure this drain does not sag or
become twisted in the middle. The drain tube supplied
with the furnace may need to be trimmed.
19
Pressure Switch Tubing
WARNING:
AVERTISSEMENT:
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
RISQUE DE CHOC ÉLECTRIQUE, D’INCENDIE
OU D’EXPLOSION
Failure to follow safety warnings exactly could
result in serious injury or property damage.
Le non-respect des avertissements de sécurité
pourrait entraîner un fonctionnement dangereux
de l’appareil, des blessures graves, la mort ou des
dommages matériels.
Improper servicing could result in dangerous
operation, serious injury, death or property
damage.
Before servicing, disconnect all electrical
power to furnace.
Un entretein incorrect pourrait entraîner un
fonctionnement dangereux de l’appareil, des
blessures graves, la mort ou des dommages
matériels
Couper toute alimentation électrique au
générateur d’air chaud avant de prodéder aux
travaux d’entretein.
Figure 17 displays the proper routing of pressure switch tubing for *MQ furnaces. All upflow / horizontal furnaces have
two pairs of switches. One set is connected to the static tap on the inducer assembly and the other to the collector
box. IMPORTANT! The static tap on the inducer is located behind the 220V motor control. Disconnect all
electrical power to the furnace before reaching behind the motor control.
Figure 17
NOTE: Control board omitted from illustration for clarity of pressure tube installation. Do not remove control board.
Figure 17. Pressure Switch Tubing for *MQ Upflow / Horizontal Furnaces
20
GAS SUPPLY & PIPING
WARNING:
FIRE OR EXPLOSION HAZARD
• Failure to follow safety warnings exactly could
result in serious injury or property damage.
• Installation and service must be performed
by a qualified installer, service agency or the
gas supplier.
• Do not store or use gasoline or other
flammable vapors and liquids in the vicinity
of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not
use any phone in your building.
• Leave the building immediately.
• Immediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s
instructions.
• If you cannot reach your gas supplier, call
the fire department.
AVERTISSEMENT:
RISQUE D’INCENDIE OU D’ EXPLOSION
• Le non-respect des avertissements de
sécurité pourrait entraîner des blessures
graves, la mort ou des dommages matériels.
• L’installation et l’entretien doivent être
effectués par un installateur qualifié, un
organisme de service ou le fournisseur de
gazstaller, service agency or the gas supplier.
• Ne pas entreposer ni utiliser de l’essence ni
d’autres vapeurs ou liquides inflammables
dans le voisinage de cet appareil, ni de tout
autre appareil.
QUE FAIRE S’IL Y A UNE ODEUR DE GAZ
• Ne pas tenter d’allumer aucun appareil.
• Ne toucher à aucun interrupteur électrique;
n’utiliser aucun téléphone dans le bâtiment.
• Évacuer l’immeuble immédiatement.
• Appeler immédiatement le fournisseur de
gaz en employant le téléphone d’un voisin.
Respecter à la lettre les instructions du
fournisseur de gaz.
• Si personne ne répond, appeler le service
des incendies.
All gas piping must be installed in compliance with local
codes and utility regulations. In the absence of local codes
the gas line installation must comply with the latest edition
of the National Fuel Gas Code (ANSI Z223.1) or (CAN/
CGA B149.1 or .2) Installation Codes.
IMPORTANT NOTES:
• Some local regulations require the installation of a
manual main shut-off valve and ground joint union
external to the furnace as depicted in Figure 18,
(page 22). The shut-off valve should be readily
accessible for service and/or emergency use.
Consult the local utility or gas supplier for additional
requirements regarding placement of the manual
main gas shut-off.
• Gas piping must never run in or through air ducts,
chimneys, gas vents, or elevator shafts.
• Compounds used on threaded joints of gas piping
must be resistant to the actions of liquefied
petroleum gases.
• The main gas valve and main power disconnect to
the furnace must be properly labeled by the installer
in case emergency shutdown is required.
• Flexible gas connectors are not recommended for
this type of furnace but may be used if allowed by
local jurisdiction. Only new flexible connectors may
be used. Do not reuse old flexible gas connectors.
• A drip leg should be installed in the vertical pipe
run to the unit as shown in Figure 18.
Table 9, (page 32) lists gas flow capacities for standard
pipe sizes as a function of length in typical applications
based on nominal pressure drop in the line.
The furnace may be installed for either left or right side
gas entry. When connecting the gas supply, provide
clearance between the gas supply line and the entry
hole in the furnace casing to avoid unwanted noise and/
or damage to the furnace. A typical gas service hookup
is shown in Figure 18.
Leak Check
WARNING:
FIRE OR EXPLOSION HAZARD
Failure to follow safety warnings exactly could
result in serious injury 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.
21
must be retightened. Repeat the tightening and soap
check process until bubbling ceases.
AVERTISSEMENT:
IMPORTANT NOTE
When pressure testing gas supply lines at pressures
greater than 1/2 psig (14 inch W.C.), the gas supply
piping system must be disconnected from the furnace
to prevent damage to the gas control valve. If the test
pressure is less than or equal to 1/2 psig (14 inch
W.C.), close the manual shut-off valve.
RISQUE D’INDENDIE OU D’EXPLOSION
Le non-respect des avertissements de sécurité
pourrait d’entraîner des blessures graves, la
mort ou des dommages matériels.
Ne jamais utiliser une flamme nue por
vérifier la présence des fuites de gaz. Pour
la vérification de tous les joints, utiliser
plutôt une solution savonneuse commerciale
fabriquée spécifiquement pur la détection des
fuites de gaz. Un incendie ou une explosion
peut entraîner des dommages matériels, des
blessures ou la mort.
High Altitude Application
The installation of this furnace at altitudes above 2,000
feet must meet the requirements of the National Fuel Gas
Code or local jurisdiction. In Canada, the requirements for
high altitude are different and governed by CGA B149.1.
Please consult your local code authority.
The *MQ furnace is derated by using the ALTITUDE
ADJUST screen in the iQ Drive® thermostat. Simply select
the altitude of the installation to the nearest 1,000 feet. No
adjustment of the pressure regulator or orifice change is
needed. When the selected altitude is above 2,000 feet,
the iQ Drive® thermostat will not use the higher of its
discrete input rates (“STEPS”), reducing the maximum
output. Table 4, (page 23) lists the highest running step
and its associated manifold pressures for each altitude.
After the gas piping to the furnace is complete, all
connections must be tested for gas leaks. This includes
pipe connections at the main gas valve, emergency
shutoff valve and flexible gas connectors (if applicable).
The soap and water solution can be applied on each
joint or union using a small paintbrush. If any bubbling is
observed, the connection is not sealed adequately and
Figure 18
*MQ With Left Side Entry
*MQ With Right Side Entry
6
1
6
1
2
2
See
Note “A”
See
Note “A”
9
7
7
See Note B
8
9
See Note B
3
3
5
5
4
COMPONENTS
(1) Automatic Gas Valve
(w/ manual shut-off)
(2) Burner Assembly
(3) Dripleg
(4) Elbow
(5) Ground Joint Union
(6) Manifold
(7) Pipe Nipple
(8) Plug
(9) Shut - Off Valve
NOTE A: Consult local codes for Shut-Off Valve location requirements.
NOTE B: Inducer assembly omitted from illustration for clarity of pipe installation. Do not remove the inducer
assembly.
Figure 18. Typical Gas Connections
22
Table 4
MANIFOLD
PRESSURE
(PROPANE)
ALTITUDE
ABOVE SEA
LEVEL
HIGHEST
RUNNING
STEP
MANIFOLD
PRESSURE
(NATURAL GAS)
0
1,000
11
11
3.5
3.5
10.0
10.0
MAXIMUM INPUT RATE
60,000
60,000
80,000
80,000
100,000
100,000
120,000
120,000
2,000
11
3.5
10.0
57,900
77,200
96,500
115,800
3,000
10
3.2
9.0
54,000
72,000
90,000
108,000
106,000
4,000
10
3.2
9.0
53,000
70,700
88,300
5,000
9
2.8
8.1
49,200
65,600
82,000
98,400
6,000
9
2.8
8.1
48,300
64,400
80,500
96,600
7,000
8
2.5
7.2
44,800
59,700
74,700
89,600
8,000
8
2.5
7.2
44,000
58,600
73,300
87,900
9,000
10,000
7
7
2.2
2.2
6.4
6.4
40,600
39,800
54,100
53,000
67,600
66,300
81,100
79,600
Table 4. High Altitude Deration Chart
Conversion to LP/Propane
WARNING:
The furnace was shipped from the factory
equipped to operate on natural gas. Conversion
to LP/propane gas must be performed by
qualified service personnel using a factory
supplied conversion kit. Failure to use the proper
conversion kit can cause fire, explosion, property
damage, carbon monoxide poisoning, personal
injury, or death.
Conversion to LP/propane is detailed in the installation
instructions provided with the conversion kit. Generally,
this will require the replacement of the burner orifices and
adding a jumper switch on the gas valve pressure regulator.
See Figure 21, (page 27) for jumper switch location.
•Installations in the United States: For Propane (LP)
conversion or for LP gas installations in altitudes
between 2,000 ft. and 10,000 ft. above sea level, use the
LP & High Altitude LP Gas Conversion Kit (P/N 904914)
for Installations in the United States. Please follow the
instructions provided with the kit.
•Installations in Canada: For Propane (LP) conversion or
for LP Gas installations in altitudes between zero and
4,500 ft. above sea level, use the LP & High Altitude
LP Gas Conversion Kit (P/N 904915) for Installations
in Canada. Please follow the instructions provided
with the kit.
When conversion is complete, verify that the altitude is
set properly in the ALTITUDE ADJUST Screen.
ELECTRICAL WIRING
WARNING:
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow safety warnings exactly could
result in serious injury or property damage.
Improper servicing could result in dangerous
operation, serious injury, death or property
damage.
• Before servicing, disconnect all electrical power
to furnace.
• When servicing controls, label all wires prior to
disconnecting. Reconnect wires correctly.
• Verify proper operation after servicing.”
AVERTISSEMENT:
RISQUE DE CHOC ÉLECTRIQUE, D’INCENDIE
OU D’EXPLOSION
Le non-respect des avertissements de
sécurité pourrait entraîner un fonctionnement
dangereux de l’appareil, des blessures graves,
la mort ou des dommages matériels.
Un entretein incorrect pourrait entraîner un
fonctionnement dangereux de l’appareil, des
blessures graves, la mort ou des dommages
matériels.
• Couper toute alimentation électrique au
générateur d’air chaud avant de prodéder aux
travaux d’entretein.
• Au moment de l’entretien des commandes,
étiquetez tous les fils avant de les débrancher.
S’assurer de les raccorder correctement.
• S’assurer que l’appareil fonctionne adéquatement
aprés l’entretien.
23
•Electrical connections must be in compliance with all
applicable local codes, and the current revision of the
National Electric Code (ANSI/NFPA 70).
•For Canadian installations the electrical connections
and grounding shall comply with the current Canadian
Electrical Code (CSA C22.1 and/or local codes).
CAUTION:
The Model Selection switches shown in Figure 25,
(page 34) are set by the factory and should not be
changed in the field. Altering the switch settings
will cause improper furnace operation. Consult
your training manual for additional details.
CAUTION:
Label all wires prior to disconnection when
servicing controls. Wiring errors can cause
improper and dangerous operation. Verify proper
operation after servicing.
IMPORTANT NOTE
If replacing any of the original wires supplied with the
furnace, the replacement wire must be copper wiring
and have a temperature rating of at least 105°F (40°C).
For electrical specifications, refer to the furnace
nameplate or Table 10, (page 33).
*MQ furnaces use high efficiency circulating air motors.
The variable speed motor control board (Figure 24, (page
33)) controls the airflow at a constant CFM.
Line Voltage Wiring
It is recommended that the line voltage (115 VAC) to
the furnace be supplied from a dedicated branch circuit
containing the correct fuse or circuit breaker for the furnace.
See Table 10, (page 33).
IMPORTANT NOTES
• An electrical disconnect must be installed readily
accessible from and located within sight of the
furnace. See Figure 19 or the wiring diagram label
inside of the control door. Any other wiring methods
must be acceptable to authority having jurisdiction.
• Proper line voltage polarity must be maintained in
order for the control system to operate correctly.
Verify the incoming neutral line is connected to the
white wire and the incoming “Hot” line is connected
to the black wire. The furnace will not operate unless
the polarity and ground are properly connected as
shown in Figure 19.
24
Thermostat / Low Voltage Connections
*MQ furnaces cannot be controlled by conventional
thermostats. Only an iQ Drive® thermostat available
from your distributor may be used to operate the
*MQ furnace.
Field wiring instructions for all iQ system equipment can
be found in the iQ Drive System Field Wiring Instructions
(P/N 709031). The iQ Drive® thermostat is connected to the
furnace by running 4 wires from the thermostat to terminal
P5 on the furnace control board. If this MQ furnace is part
of of an iQ Zone system, refer to Figure 20, (page 25).
Field supplied wiring is recommended to be a 4 wire
shielded cable and must be a minimum of 18 gauge.
Single Stage AC
1. Connect the C terminal on the AC unit to the C terminal
on the motor control board. See Option C.
2. Connect the Y terminal on the AC unit to the Y/Y2_OUT
terminal on the motor control board.
Two - Stage AC
1. Connect the C terminal on the AC unit to the C terminal
on the furnaces motor control board. See Option D.
2. Connect the Y1 terminal on the AC unit to the Y1_OUT
terminal on the motor control board.
3. Connect the Y2 terminal on the AC unit to the Y/
Y2_OUT terminal on the motor control board.
Single Stage Heat Pump
1. Connect the W2 terminal on the heat pump to the
Y1/E input terminal on the motor control board. See
Option E.
2. Connect the C terminal on the heat pump to the C
terminal on the motor control board.
3. Connect the R terminal on the heat pump to the R
terminal on the motor control board.
4. Connect the Y terminal on the heat pump to the Y/Y2
output terminal on the motor control board.
5. Connect the O terminal on the AC unit to the W/0
output terminal on the motor control board.
Two - Stage Heat Pump
1. Connect the W2 terminal on the heat pump to the
Y1/E input terminal on the motor control board. See
Option F.
2. Connect the C terminal on the heat pump to the C
terminal on the motor control board.
3. Connect the R terminal on the heat pump to the R
terminal on the motor control board.
4. Connect the Y terminal on the heat pump to the Y1
output terminal on the motor control board.
5. Connect the Y2 terminal on the heat pump to the Y/
Y2 output terminal on the motor control board.
6. Connect the O terminal on the AC unit to the W/0
output terminal on the motor control board.
Figure 19Junction Box (may be int. or ext. to the furnace). These
Field Supplied
Fused Service
Panel
Field Supplied
Disconnect w/in
Sight of Furnace
connections can be made in the field supplied disconnect
at the furnace. NOTE: Connections made within the furnace
burner compartment do not require a junction box.
Black (Hot)
Black
Black
White (Neutral)
White
White
Green or Bare
(Ground)
Black
White
Ground
Ground
Ground
Field Supplied
Panel Connector
Field Line Voltage Wiring
Factory Line Voltage Wiring
Figure 19. Line Voltage Field Wiring
Figure 20
R
OPTION A - Low Voltage Field Wiring
(MQ Furnace Without iQ Zone System)
A+
OPTION B - Low Voltage Field Wiring
(MQ Furnace With iQ Zone System)
iQ
T-STAT
B-
ON
3 2 1
Model
Selection
Switch
C
MODULATING
FURNACE
BOARD
GREEN
RED
ON
3 2 1
Model
Selection
Switch
R
DX+
DXC
YELLOW
MODULATING
FURNACE
BOARD
GREEN
RED
R
A+
BC
iQ
T-STAT
Grn A - B +
R
DX+
DXC
YELLOW
OPTION D - Low Voltage Field Wiring
(Conventional Two-Stage AC)
FURNACE
FURNACE
R
MODULATING
DX+
FURNACE
DXBOARD
C
R
MODULATING DX+
FURNACE
DXBOARD
C
OUTPUTS
VAR. SPEED
W/0
Y/Y2 MOTOR BOARD
Y1
H
INPUTS
To iQ Zone Equipment
R
A+
BC
iQ
T-STAT
OUTPUTS
VAR. SPEED
W/0
Y/Y2 MOTOR BOARD
Y1
H
INPUTS
SINGLE STAGE
AC UNIT
Y1/E
SENSOR
GND
R
C
iQ Zone
System Controller
A
B
OFF
OPTION C - Low Voltage Field Wiring
(Conventional Single-Stage AC)
iQ
T-STAT
B-
C
OFF
R
A+
TWO STAGE
AC UNIT
Y1/E
SENSOR
GND
R
C
C
R
Y1
Y2
C
Y
R
A+
OPTION E - Low Voltage Field Wiring
(Conventional Single Stage Heat Pump)
BC
iQ
T-STAT
OPTION F - Low Voltage Field Wiring
(Conventional Two Stage Heat Pump)
R
A+
BC
OD
OD
FURNACE
FURNACE
GND
GND
R
MODULATING DX+
FURNACE
DXBOARD
C
OUTPUTS
VAR. SPEED
W/0
Y/Y2 MOTOR BOARD
Y1
H
INPUTS
R
C
HUMIDIFIER
(OPTIONAL)
iQ
T-STAT
Y1/E
SENSOR
GND
R
MODULATING DX+
FURNACE
DXBOARD
C
OUTDOOR
TEMP.
SENSOR
OUTPUTS
VAR. SPEED
W/0
Y/Y2 MOTOR BOARD
Y1
H
INPUTS
SINGLE STAGE
NON-iQ HEAT PUMP
(OUTDOOR UNIT)
W2
C
R
Y
O
R
C
HUMIDIFIER
(OPTIONAL)
Y1/E
SENSOR
GND
OUTDOOR
TEMP.
SENSOR
TWO STAGE
NON-iQ HEAT PUMP
(OUTDOOR UNIT)
W2
C
R
Y
Y2
O
Figure 20. iQ Wiring Configurations
25
If installing a single or two-stage conventional heat pump,
it is recommended that an outdoor temperature sensor
(920938) be installed on the system. The sensor connects
to the iQ thermostat as shown in Options E & F in Figure
20, (page 25) and measures the outdoor temperature
at the unit. The outdoor temperature is displayed on the
main screen of the iQ thermostat and the system switches
between furnace and heat pump based on the outdoor
temperature.
START-UP & ADJUSTMENTS
WARNING:
ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD
Failure to follow safety warnings exactly could result
in serious injury or property damage.
Improper servicing could result in dangerous
operation, serious injury, death or property damage.
Grounding
WARNING:
To minimize personal injury, the furnace cabinet
must have an uninterrupted or unbroken electrical
ground.The controls used in this furnace require
an earth ground to operate properly. Acceptable
methods include electrical wire or conduit
approved for ground service. Do not use gas
piping as an electrical ground!
• Before servicing, disconnect all electrical power
to furnace.
• When servicing controls, label all wires prior to
disconnecting. Reconnect wires correctly.
• Verify proper operation after servicing.”
AVERTISSEMENT:
RISQUE DE CHOC ÉLECTRIQUE, D’INCENDIE
OU D’EXPLOSION
Le non-respect des avertissements de sécurité
pourrait entraîner un fonctionnement dangereux
de l’appareil, des blessures graves, la mort ou des
dommages matériels.
Un entretein incorrect pourrait entraîner un
fonctionnement dangereux de l’appareil, des
blessures graves, la mort ou des dommages matériels
• Couper toute alimentation électrique au
générateur d’air chaud avant de prodéder aux
travaux d’entretein.
• Au moment de l’entretien des commandes,
étiquetez tous les fils avant de les débrancher.
S’assurer de les raccorder correctement.
• S’assurer que l’appareil fonctionne adéquatement
aprés l’entretien.
Pre-Start Check List
√Verify the polarity of the connections are correct, the
line voltage power leads are securely connected and
the furnace is properly grounded.
√Verify the thermostat wires (R, DX+, DX-, & C) are
securely connected to the correct leads on the terminal
strip of the circuit board. See Figure 20, (page 25).
√Verify the gas line service pressure does not exceed
10.0 inches of water column, and is not less than 4.5
inches W.C. for natural gas. For LP gas the line service
pressure must not exceed 14 in. W.C., and must not be
less than 11.0 in. W.C.
√Verify the manual reset roll-out switch is closed.
If necessary, press the button to reset the switch.
DO NOT install a jumper wire across a switch to
defeat its function. If a switch reopens on start-up,
DO NOT reset the switch without identifying and
correcting the fault condition.
26
√Verify the blower door is in place, closing the door switch
in the line voltage circuit.
√Verify the gas line has been purged and all connections
are leak free.
System Configuration
Before applying gas to the furnace, the iQ system must
be configured to the appliance(s) it is connected to. MQ
furnaces, iQ Drive® air conditioners and iQ Drive® heat
pumps are identified automatically when power is supplied
to the thermostat. Conventional (non-iQ) heating or cooling
appliances must be configured manually.
Use the System Configuration screen to verify the
configuration is correct. After accepting the configuration,
set the desired furnace rise.
If the installation is at an altitude of 2,000 feet or more,
set the altitude in the ALTITUDE ADJUST Screen.
Start-up Procedures
Do not perform these steps until all of the checks in the
previous steps have been completed:
1. Set the thermostat mode to HEAT.
2. Set the thermostat setpoint to 5° below room
temperature.
3. Turn off all electrical power to the furnace.
4. Follow the Operating Instructions on the furnace label.
5. Set the thermostat above room temperature and verify
the Operating Sequence (page 28).
6. After 5 minutes of operation, set the thermostat
below room temperature and verify steps 8 & 9 of the
Operating Sequence.
Verifying & Adjusting the Input Rate
IMPORTANT NOTE: The input rate must not exceed
the rate shown on the furnace rating plate. At altitudes
above 2,000 feet, it must not exceed that on the rating
plate less 4% for each 1,000 feet.
The input rate must be verified for each installation to
prevent over-firing of the furnace. To determine the exact
input rate, perform the following procedures:
1. Shut off all other gas fired appliances.
2. Start and run the furnace for at least 3 minutes.
3. View the furnace status screen and verify the furnace
is operating at full capacity. The Highest Running Step
and Maximum Input Rate for various altitudes is listed
in Table 5, (page 30)
4. Measure the time (in seconds) required for the gas
meter to complete one revolution.
5. Convert the time per revolution to cubic feet of gas
per hour using Table 8, (page 32).
6. Multiply the gas flow rate in cubic feet per hr by the
heating value of the gas in Btu per cubic ft to obtain
the input rate in Btuh. See example above.
7. The manifold pressure must be set to the appropriate
value for each installation by a qualified installer, service
agency or the gas supplier.
Example:
•Time for 1 revolution of a gas meter with a 1 cubic
foot dial = 40 seconds.
•From Table 9 read 90 cubic ft gas per hr.
•Local heating value of the gas (obtained from gas
supplier) = 1,040 Btu per cubic foot.
•Input rate = 1,040 x 90 = 93,600 Btuh.
WARNING:
Do not attempt to drill the gas orifices. Use only
factory supplied orifices. Improperly drilled
orifices may cause fire, explosion, carbon
monoxide poisoning, personal injury or death.
a.) Obtain the manifold pressure setting required for
this installation by referring to Table 4.
b.) Using a small screw driver, turn the adjusting
screw (Figure 21) on the regulator to adjust the full
input setting.
IMPORTANT NOTE: Turning the adjusting
screw clockwise increases the pressure and
counterclockwise reduces the pressure.
Verifying & Adjusting Temperature Rise
Confirm the temperature rise through the furnace is
within the limits specified on the furnace rating plate. Any
temperature rise outside the specified limits could result
in premature failure of the heat exchanger.
1.Place thermometers in the return and supply air
stream as close to the furnace as possible. To avoid
false readings, the thermometer on the supply air side
must be shielded from direct radiation from the heat
exchanger.
2. Adjust all registers and duct dampers to the desired
position. Run the furnace for 10 to 15 minutes on
Figure 21
Manifold
Adjustment Screw
+
Jumper
Switch
Figure 21. Modulating Gas Valve
27
the maximum step for your altitude in Table 4 before
taking any temperature readings. The temperature
rise is the difference between the supply and return
air temperatures.
For typical duct systems, the temperature rise will fall within
the limits specified on the rating plate If the measured
temperature rise is not the correct value, choose another
rise or adjust your ductwork.
Verifying Burner Operation
CAUTION:
The door over the burners may only be open
for inspection purposes only. The door must be
installed during unattended operation.
1. Remove the burner compartment door.
2. Set the thermostat above room temperature and
observe the ignition sequence.The burner flame should
carry over immediately between all burners without
lifting off, curling, or floating. The flames should be
blue, without yellow tips.
3. After validating flame characteristics, change
thermostat setting to below room temperature.
4. Verify burner flame is completely extinguished.
5. Replace the burner compartment door.
Verifying Operation of the Supply Air Limit
Switch
NOTE: A properly functioning limit switch should turn off
the gas valve when the return is blocked (time depends on
how well the return air is blocked). When the limit switch
opens, the inducer blower should run for 30 seconds and
the circulating air blower will run continuously
1. Check the blower door and verify that it is securely
mounted in place and that there is power to the furnace.
2. Block the return airflow to the furnace by installing a
close-off plate in place of or upstream of the filter(s).
3. Set the thermostat above room temperature and
observe the Operating Sequence.
4. Remove the close-off immediately after the limit switch
opens. If the furnace continues to operate with no
return air, set the thermostat to a temperature below
room temperature, shut off the power to the furnace,
and replace the limit switch.
28
OPERATING SEQUENCE
The operating sequences for the heating, cooling, and fan
modes are described below. Refer to the field electrical
diagrams and furnace wiring diagrams. See Figure 19,
(page 25), Figure 20, (page 25) and Figure 25, (page
34).
Heating Cycle
1. The thermostat calls for heat through the communication
cable.
2. The control checks the availability of the pressure
switches.
a.) If the switches are closed, the furnace will shut
down for 5 minutes before retrying.
b.) If the pressure switches are open, the control
energizes the inducer and waits for the low pressure
switches to close. The low pressure switches must
close within 12 seconds.
3. The control runs the inducer for a 30 second pre-purge.
4. The control energizes the igniter output for an adaptive
warm-up time limit.
5. The furnace ignites the burners at 75% (Step 6)
of maximum input rate. The thermostat will choose
different inputs after the flames have stabilized.
6. If the flame is proved and ignites the gas, the control
de-energizes the igniter. The gas valve and inducer
remains energized. The control goes to blower on
delay.
7. The control energizes the blower on the selected speed
10 seconds after the gas valve opens. The gas valve
and inducer remain energized.
a.) If the heating load is 75% of maximum input or less,
the low pressure switches must remain closed. If
any of the low pressure switches are open, the
furnace will shut down.
b.) If the heating load is greater than 75%, the high
pressure switches must be closed. If any of the
high pressure switches are open, the furnace will
only operate below 75% of maximum input rate.
c.) If both high and low pressure switches are open,
the furnace will shut off.
8. When the thermostat demand for heat is satisfied, the
control de-energizes the gas valve. The inducer output
remains on for a 30 second post-purge period.
9. The circulating air blower will continue to run for the
selected Blower Off Delay as set in the Blower OFF
Delay screen.
Cooling Cycle
The iQ Drive® thermostat handles cooling in two ways:
•For iQ Drive® Ready air conditioners and heat pumps,
the thermostat communicates directly to the appliances
through the communications cable, turning on the
cooling appliance and furnace blower.
•For conventional 1 or 2 stage air conditioners or heat
pumps/, the thermostat communicates to the furnace
through the communications cable. The furnace then
issues the call for cooling through the Y/Y2 or Y1 and
W/0 terminals on the motor control board.
•The thermostat also issues commands to energize the
furnace circulating air blower. When the demand for
cooling is satisfied, the thermostat turns off the cooling
appliance. The furnace blower continues to operate for
30 seconds before shutting down.
Fan Mode
If continuous fan is selected through the Mode Screen,
the iQ Drive® thermostat communicates this command
through the communications cable.
•If there is no demand for heating or cooling, the blower
runs at the speed selected in the manual fan speed
screen.
•If a call for cooling is received, the furnace will change
to a blower speed that is needed for cooling.
•If a command for heating is received, the blower will
change to the required speed.
Intermittent Fan Mode
In this mode, occasional air circulation can be programmed
through the intermittent fan screen. The circulating blower
will cycle on and off at a reduced blower speed. If there
is a call for heating or cooling, it takes precedence over
intermittent operation.
MAINTENANCE
WARNING:
These maintenance instructions are primarily
intended to assist qualified technicians
experienced in the proper maintenance and
operation of this appliance.
Proper maintenance is most important to achieve the best
performance from a furnace. Follow these instructions for
years of safe, trouble free operation.
•Always reinstall the doors on the furnace after servicing
or cleaning/changing the filters. Do not operate the
furnace without all doors and covers in place.
•Verify that the thermostat is properly installed and is not
affected by drafts or heat from lamps or other appliances.
•To achieve the best performance and minimize
equipment failure it is recommended that a yearly
maintenance checkup be performed. At a minimum, this
check should include the following items:
Blower Compartment - Dirt and lint can create excessive
loads on the motor resulting in higher than normal operating
temperatures and shortened service life. It is recommended
that the blower compartment be cleaned of dirt or lint
that may have accumulated in the compartment or on
the blower and motor as part of the annual inspection.
Air Filter(s) - Air filter(s) are not supplied with the furnace
as shipped from the factory. The installer must provide a
high velocity filter and rack for a filter in the return air duct
adjacent to the furnace, or in a return air grill to the furnace.
WARNING:
Never operate the furnace without a filter in
place. Dust and lint in the return air can build
up on internal components, resulting in loss of
efficiency, equipment damage, and possible fire.
It is recommended that filters be cleaned or replaced
monthly. New or newly renovated homes may require
more frequent changing until the construction dust has
minimized.
Filters designed to remove smaller particles such as
pollen, may require additional maintenance. Filters for
side return and bottom return applications are available
from most local distributors.
Cleaning of Burners - If the burners must be cleaned,
follow the steps below and see page 39 for component
descriptions and locations.
1. Shut off gas supply to the furnace at the meter or at
a manual valve in the supply piping.
2. Turn off all power to the furnace and set the thermostat
to it’s lowest setting.
3. Remove the burner door from the furnace.
4. Turn the gas control switch to the OFF position.
29
5. Disconnect the wires from the gas valve, igniter, flame
sensor, and flame rollout switch.
6. Using two wrenches, separate the ground-joint union
in the gas supply piping at the furnace.
7. Remove the piping between the Gas Valve and the
ground-joint union. (If applicable).
8. Remove all screws securing the Manifold Assembly
to the Burner Box.
9. Carefully remove the burner assembly from the
furnace. DO NOT DAMAGE THE IGNITER WHILE
REMOVING THE BURNER ASSEMBLY.
10.Inspect the burners for accumulated dust or debris.
If necessary carefully clean them with a soft wire
brush and a vacuum cleaner. DO NOT DAMAGE THE
IGNITER WHILE CLEANING THE BURNER.
11.Replace all the parts in reverse order that they were
removed.
12.Follow the lighting instructions found on the furnace
door to return the furnace to operation. Verify proper
operation after servicing.
Heat Exchanger & Burner - The furnace should operate for
many years without soot buildup in the flue passageways,
however, the flue, vent system, and burners should be
inspected and cleaned (if required) by a qualified service
technician annually to ensure continued safe operation.
Pay attention to any deterioration from corrosion or other
sources.
WARNING:
Holes in the vent pipe or heat exchanger can
cause combustion products to enter the home.
Replace the vent pipe or heat exchanger if leaks
are found. Failure to prevent the circulation of
combustion products into the living space can
create potentially hazardous conditions including
carbon monoxide poisoning that could result in
personal injury or death.
Venting System - Check the inlet pipe (if applicable)
and outlet pipe to ensure they are not blocked by debris.
Any damaged section of vent pipe must be replaced,
and any obstruction or blockage must be removed prior
to operating the furnace.
TROUBLESHOOTING
If the furnace fails to operate check the following:
•Is the thermostat operating properly?
•Are the blower compartment door(s) in place?
•Is the furnace disconnect closed?
•Has the circuit breaker tripped or the control board fuse
burned open?
•Is the gas turned on?
•Are any manual reset switches open?
•Is the filter dirty or plugged?
•Is the flame sensor coated? (Remove and clean with
steel wool. (Do not use emery cloth or sandpaper!)
•Is there blockage in the condensate drain tube? Also
verify that there is no double trapping of condensate.
•Is the secondary heat exchanger free of debris and
clogs?
•Is evaporator coil clean and free of debris (If applicable).
•Are all the LED’s on the furnace and motor control
boards constantly ON? If not, refer to Table 5 & Table
6 to determine fault condition.
IMPORTANT NOTE: The furnace will lock out after 5
failed attempts for ignition and will try again every
hour if the call for heat remains.
•If the Inducer Blower is operating, and items above have
been verified, check the Blower Limit Switch (Figure 29,
(page 39) and reset if necessary.
•If the furnace operates when the Blower Limit Switch is
reset, contact a qualified service technician to identify
and repair the problem.
•If the furnace still doesn’t operate, check the Flame
Roll-out Switches (Figure 29) and reset if necessary.
•If the furnace operates when the Flame Rollout Switch
is reset, contact a qualified service technician to identify
and repair the problem.
Table 5
DIAGNOSTIC DESCRIPTION
Control Fault (No Power)
L1/Neutral Polarity Fault
1 Hour Lockout
Normal Operation
GREEN
LED
RED
LED
Off
Flash
Off
Flash
Alternating Flash
Heart Beat
On
On
Flash
Low Pressure Switch Open Fault
Flash
On
Open Limit Switch Fault
Flash
Off
Off
Flash
Low Pressure Switch Closed Fault
High Pressure Switch Open or Closed
Fault
Table 5. Furnace Control Board Fault Conditions
Table GREEN
6
DIAGNOSTIC DESCRIPTION
LED
Control Fault (No Power)
Normal Operation
Motor Fault
Communications Fault
RED LED
Off
Heart Beat
Off
On
On
Flash
Flash
Flash
Table 6. Motor Control Board Fault
Conditions - Variable Speed
30
FIGURES & TABLES
Upflow
Cabinets
Dim.
“A”
Dim.
“B”
Dim.
“C”
‘B’ Cabinet
17 1/2
21
24 1/2
15 7/8
19 3/8
22 7/8
16 1/8
19 5/8
23 1/8
‘D’ Cabinet
BOTTOM VIEW
B
C
Front Brace
FL
AN
S
3 1/4
Electric (Ø 7/8)
Vent pipe
(Ø 3”)
Gas
(Ø 1 5/8)
22 1/2
22 1/2
Gas (Ø 1 5/8)
17 7/8
24 7/8
Vent pipe
(Ø 3”)
17 1/4
34 1/2
T-stat
(Ø 7/8)
A
Electric
(Ø 7/8)
25 3/8
Bottom
Panel
Combustion Air
T-stat
(Ø 7/8)
2 3/4
22 1/2
19
GE
NOTE: Dimensions shown in inches.
23 1/2
‘C’ Cabinet
Figure 22
TOP VIEW
4 Knockouts
(both sides)
1
15
Cond. (Ø 1 1/16)
28
23
Condensate
(Ø 1 1/16)
LEFT SIDE
FRONT VIEW
1 1/4
RIGHT SIDE
Figure 22. *MQ Cabinet Dimensions
Airflow Data
GAS INPUT
RATE
(BTUH)
7
TARGET CFM Table
FOR SELECTED
CIRCULATING AIR
TEMPERATURE RISES, °F
45
50
55
60
FULL
INPUT
MINIMUM
INPUT
FULL
INPUT
MINIMUM
INPUT
FULL
INPUT
MINIMUM
INPUT
FULL
INPUT
MINIMUM
INPUT
CONSTANT
60,000
80,000
1,110
1,480
635
850
1,000
1,345
560
740
940
1,255
515
685
850
1,140
470
625
950
1,300
100,000
120,000
1,850
2,225
1,050
1,270
1,680
2,020
925
1,115
1,565
1,890
855
1,025
1,460
1,730
780
940
1,760
2,100
NOTE: This table lists the HIGH and LOW target CFMs for each maximum input rate and temperature rise. If the target CFM is more that 1,600
CFM, it is recommended that two return air openings into the furnace be used.
Table 7. Modulating Furnace CFM Targets
31
Gas Information
Table 8
GAS FLOW RATES
(CUBIC FEET PER HOUR)
CUBIC FEET PER REVOLUTION
OF GAS METER
TIME FOR ONE
REVOLUTION
(SECONDS)
GAS FLOW RATES
(CUBIC FEET PER HOUR)
CUBIC FEET PER REVOLUTION
OF GAS METER
1
5
10
TIME FOR ONE
REVOLUTION
(SECONDS)
1
5
10
10
12
360
300
1,800
1,500
3,600
3,000
66
68
55
53
273
265
545
529
14
257
1,286
2,571
70
51
257
514
16
225
1,125
2,250
72
50
250
500
18
200
1,000
2,000
74
49
243
486
20
180
900
1,800
76
47
237
474
22
164
818
1,636
78
46
231
462
24
150
750
1,500
80
45
225
450
26
138
692
1,385
82
44
220
439
28
129
643
1,286
84
43
214
429
30
120
600
1,200
86
42
209
419
32
113
563
1,125
88
41
205
409
34
106
529
1,059
90
40
200
400
36
100
500
1,000
92
39
196
391
38
95
474
947
94
38
191
383
40
90
450
900
96
38
188
375
42
86
429
857
98
37
184
367
44
82
409
818
100
36
180
360
46
78
391
783
102
35
176
353
48
75
375
750
104
35
173
346
50
72
360
720
106
34
170
340
52
69
346
692
108
33
167
333
54
67
333
667
110
33
164
327
56
64
321
643
112
32
161
321
58
62
310
621
114
32
158
316
60
60
300
600
116
31
155
310
62
64
58
56
290
281
581
563
118
120
31
30
153
150
305
300
Table 8. Gas Flow Rates
Table 9
CAPACITY OF BLACK IRON GAS PIPE (CU. FT. PER HOUR)
FOR NATURAL GAS (SPECIFIC GRAVITY - 0.60)
NOMINAL BLACK IRON
PIPE DIAMETER (IN.)
10
1/2
130
90
75
65
3/4
280
190
150
130
1
520
350
285
245
1 1/4
1,050
730
590
1 1/2
1,600
1,100
890
LENGTH OF PIPE RUN (FT)
20
30
Cubic Feet Per Hour Required =
50
40
60
70
80
55
50
45
40
115
105
95
90
215
195
180
170
500
440
400
370
350
760
670
610
Input To Furnace (Btu/hr)
Heating Value of Gas (Btu/Cu. Ft.)
NOTE: The cubic feet per hour listed in the table above must be greater than the cubic feet per hour of gas flow required by
the furnace. To determine the cubic feet per hour of gas flow required by the furnace, divide the input rate of the furnace by the
heating value (from gas supplier) of the gas.
Table 9. Gas Pipe Capacities
32
Electrical Diagrams
Table 10
FURNACE
INPUT
(BTUH)
CABINET
WIDTH
(IN.)
NOMINAL
ELECTRICAL
SUPPLY
MAXIMUM
OPERATING
VOLTAGE
MINIMUM
OPERATING
VOLTAGE
MAXIMUM
FURNACE
AMPERES
MAXIMUM
FUSE OR CIRCUIT
BREAKER AMPS**
60,000
17 ½
115-60-1
127
103
7.2
15
80,000
21
115-60-1
127
103
9.4
15
100,000
21
115-60-1
127
103
9.4
15
120,000
24 ½
115-60-1
127
103
11.9
15
RECOMMENDED THERMOSTAT WIRE LENGTH
THERMOSTAT WIRE GAUGE
2 - WIRE
(HEATING)
4 OR 5 WIRE
(COOLING)
24
55 ft.
25 ft.
22
90 ft.
45 ft.
20
140 ft.
70 ft.
18
225 ft.
110 ft.
** Time-delay fuses or HACR-type circuit breakers are required.
3
OFF
OFF
6
3
80,000
ON
OFF
OFF
5
2
100,000
OFF
ON
OFF
4
1
120,000
ON
ON
OFF
VP
RX
TX
TR
MVT
Figure
23LIGHTS
STATUS
1
2
3
L1-IN
Y1_OUT
OFF
L1-OUT
H_OUT
NOT USED ON
iQ SYSTEMS
GROUND
P3
MOTOR WIRING
HARNESS
Figure 23. Variable Speed Motor Control Board
1
2
3
4
C
5
XFMR-N
LINE-N
LINE-N
EAC-N
P2
LINE
EXPANSION PORT
LINE OUT
SENSOR
C
BROWN
GREEN
XFMR
COMMUNICATION
CABLE TERMINAL
Y1_E
EAC
R
1 2 3 4 5 6 78
YELLOW
RED
DHUM_IN
INPUT TERMINALS
NOT FOR
FIELD USE
ORANGE
ON
RED
RED
Y/Y2_OUT
Model Selection
Switch
L2-IN
GREEN
L2-OUT
W_OUT
YELLOW
2
OFF
GREEN
1
60,000
RED
SWITCH NUMBER
Btuh Input
DXCOMMUNICATION
CABLE TERMINAL
R
3 AMP
FUSE
DX+
Figure 24
24V
COM
Table 10. Wire Length & Voltage Specifications
Figure 24. Modulating Furnace Control Board
33
BLUE
BLACK
WHITE
BLUE
DOOR
SWITCH
VENT LIMIT
XFMR
LINE
INDUCER
BLACK
1
2
3
Figure 25. Wiring Diagram for Variable Speed Modulating Furnaces
1 1
2 2
IGNITOR
Inducer Drive
(PWM Drive)
GREEN RED
YELLOW
R
DX+
DXC
ORANGE
YELLOW
BROWN
RED
GREEN
GREEN
5
4
3
1
2
VP ORANGE
YELLOW
RX BROWN
TX
RED
TR GREEN
MVT
TH
RH
RX
TX
24V
3 AMP FUSE
IQ THERMOSTAT/
CONTROLLER
120 V
BLACK
LINE-N
LEGEND:
FLAME
ROLL-OUT
BLUE
GREEN
RED
YELLOW
BROWN
ORANGE
1
4
3
2
5
6
BLACK
WHITE
24 V
WHITE
GREEN
XFMR-N
FIELD WIRING
LOW VOLTAGE
HIGH VOLTAGE
MVT
TR
TX
RX
TH
VIOLET
RED
PRESSURE
SWITCH
PRESSURE
SWITCH
1 2 3 4
1 2 3 4
EAC
WHITE (NEUTRAL)
BLACK 120V
GROUND
SUPPLY
AIR LIMIT
GAS
VALVE
VIOLET
HIGH
ORANGE
FLAME SENSOR
PRESSURE
SWITCH
PRESSURE
SWITCH
ORANGE
VIOLET
ORANGE
WHITE
LOW
Use copper conductors only.
If any of the original wire as supplied with the
furnace must be replaced, it must be replaced
with wiring material having a temperature
rating of at least 105 degrees C.
BLACK
Refer to the Installation Istructions
provided with the kit for the proper
heating and cooling speeds for your
application.
LINE
BLACK
BLUE
BLACK
WHITE
WHITE
GREEN
RED
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
BLUE
BLACK
WHITE
RED
YELLOW
WHITE
GREEN
TO
OUTDOOR
UNIT
BLACK
W/O
Y/Y2
RED
GREEN
L2-OUT
L2-IN
BLACK
MOTOR CHOKE
(ON 3/4 AND 1HP
MOTORS ONLY)
L1-IN
For 97+ Modulating Gas Furnaces
24V
BLACK
COM
BLACK
Y1
H
RED
BLOWER
LIMIT
R
R
C
RX
GND
TX
W
C
R
DX+
DXC
F lash
RED
RED
04/11
711001B
(Replaces 711001A)
CFM
MOTOR
Yellow LED
C ontinuous F lash
On
O ff
BLOWER
LIMIT
BLUE
BLUE
PWM
MODE
SPEED
FAULT
COMMON
HP
OPEN
OPEN
DHUM Y1/E SEN GND
WHITE
BLACK
PART OF
MOTOR
Diagnostic Description
Low flam e S ensor S ignal
F lam e P resent
Red LED
O ff
O ff
F la sh
F lash
A lternating F lash
Heartbeat
On
On
F lash
F la sh
On
F la sh
O ff
Green LED
FAULT CONDITIONS
Diagnostic Description
C o ntro l F a ult (N o P o w er)
L1/neutral pola rity F ault
1 H our L o c k o u t
N o r m a l O p e r a t io n
Low P ressure S w itch C losed F ault
Low P ressure S w itch O pen F ault
O pen Lim it S w itch F a ult
H igh P ressure S w itch O pen or
C losed F ault
L1-OUT
WIRING DIAGRAM
C
DXDX+
R
WHITE
1 2 3
1 2 3
34
Figure 25
LINE-N
EAC-N
Venting Information
Table 11
AIR SUPPLY INLET
VENT TERMINAL
AREA WHERE TERMINAL IS NOT PERMITTED
CANADIAN INSTALLATIONS
a
US INSTALLATIONS
b
Direct Vent (2-pipe) &
Conventional Vent (1-pipe)
Furnaces
Direct Vent
(2-pipe) Furnaces
Conventional Vent
(1-pipe) Furnaces
12 inches (30cm)
12 inches (30cm)
12 inches (30cm)
6 inches (15cm) for
appliances < 10,000 Btuh (3kW)
6 inches (15cm) for
appliances < 10,000 Btuh (3kW)
12 inches (30cm) for appliances
10,000 Btuh - 100,000 Btuh (30kW)
9 inches (23cm) for appliances
10,000 Btuh - 50,000 Btuh (30kW)
36 inches (91cm) for
appliances > 100,000 Btuh (30Kw)
12 inches (30cm) for
appliances > 50,000 Btuh (30Kw)
C = Clearance to permanently closed window
*
*
*
Vertical clearance to ventilated soffit located
above the terminal within a horizontal distance
D=
of 2 feet (61cm) from the center line of the
terminal.
*
*
*
*
*
*
*
*
*
*
*
*
3 feet (91cm) within a height 15 feet
above the meter/regulator assembly
Clearance Location
A=
B=
Clearance above grade, veranda, porch, deck,
balcony, or maximum expected snow level.
Clearance to window or door
that may be opened.
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.
I = Clearance to service regulator vent outlet.
Clearance to non-mechanical air supply inlet to
J = building or the combustion air inlet to any other
appliance.
K = Clearance to mechanical air supply inlet.
L=
Clearance above paved sidewalk or driveway
located on public property.
M=
Clearance under veranda, porch, deck, or
balcony.
4 ft. (1.2m) below or to side
of opening; 1 ft. (300mm)
above opening
*
*
3 feet (1.83m)
*
*
6 inches (15cm) for
appliances < 10,000 Btuh (3kW)
6 inches (15cm) for
appliances < 10,000 Btuh (3kW)
12 inches (30cm) for appliances
10,000 Btuh - 100,000 Btuh (30kW)
9 inches (23cm) for appliances
10,000 Btuh - 50,000 Btuh (30kW)
36 inches (91cm) for
appliances > 100,000 Btuh (30Kw)
12 inches (30cm) for
appliances > 50,000 Btuh (30Kw)
6 feet (1.83m)
3 feet (91cm) above if within
10 feet (3m) horizontally
3 ft. (91cm) above if within
10 feet (3m) horizontally
*
7 ft. (2.13m)
*
*
7 feet (2.13m)
c
12 inches (30cm)
d
4 ft. (1.2m) below or to side
of opening; 1 ft. (300mm)
above opening
a: In accordance with the current CSA B149.1 Natural Gas and Propane Installation Guide Code
b: In accordance with the current ANSI Z223.1 / NFPA 54 Natural Fuel Gas Code
c: A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.
d: Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
* For clearances not specified in ANSI Z223.1 / NFPA 54 or CSA B149.1, the following statement shall be included: “Clearance in accordance with local installation
codes, and the requirements of the gas supplier and the manufacturers installation instructions”
Table 11. Vent Termination Clearances
35
26 OPTIONS
UPFLOW -Figure
1 PIPE
Plug
PVC Tee
PVC Trap
Plug
See
NOTE 5
FLUE PIPE
X
COMBUSTION
AIR
FLUE PIPE
COMBUSTION
AIR
X
See
NOTE 5
PVC Tee
Rubber
Grommet
PVC Trap
OPTION 1
OPTION 2
Rubber
Grommet
See View B for drain line positions
See View A for drain line positions
VIEW -A-
VIEW -B-
Drain Line Attached
to PVC Trap
(Field Supplied)
Inline Drain Tube
(Factory Supplied)
See NOTE 4
Collector Box Drain
(Factory Equipped)
See NOTE 2
Inline Drain
(Field Supplied)
See NOTES 2 & 3
Collector Box Drain
(Factory Equipped)
See NOTE 2
NOTES:
1. See Accessories section (page 18) for optional PVC Tee configurations and drainage options.
2. Drain tube must be trapped with a J-Trap or field supplied loop and drained externally from the cabinet. Traps may be positioned inside or outside the cabinet.
3. Inline drain is required only if “X” is greater than 6 feet.
4. Tubing needs to be cut to length and attached during unit installation.
5. Horizontal piping from inducer to flue pipe must be sloped 1/4” per foot to ensure drainage to PVC trap.
Plug
PVC Tee
PVC Trap
Rubber
Grommet
OPTION 3
Plug
See
NOTE 5
FLUE PIPE
X
FLUE PIPE
COMBUSTION AIR
COMBUSTION AIR
UPFLOW- 2 PIPE OPTIONS
X
See
NOTE 5
PVC Tee
PVC Trap
OPTION 4
Rubber
Grommet
See View A for drain line positions
See View B for drain line positions
Figure 26. Vent Pipe & Condensate Options - Upflow Furnaces
36
Figure 27
HORIZONTAL LEFT - 1 PIPE OPTION
Rubber
Grommet
Option
6
FLUE PIPE
Option
5
FLUE PIPE
HORIZONTAL RIGHT - 1 PIPE OPTION
Rubber
Grommet
COMBUSTION
AIR
COMBUSTION
AIR
See VIEW C for
drain line positions
See VIEW D for
drain line positions
Plug
Plug
Inline Drain
(Factory Supplied)
See NOTE 3
VIEW -CVIEW -DInline Drain
(Field Supplied)
See NOTE 2
Collector Box Drain
(Factory Equipped)
See NOTE 2
Collector Box Drain
(Factory Equipped)
See NOTE 2
NOTES:
1. See Accessories section (page 18) for optional PVC Tee configurations and drainage options.
2. Drain tube must be trapped with a J-Trap or field supplied loop and drained externally from the cabinet. Traps may be positioned inside or outside the cabinet.
3. Tubing needs to be cut to length and attached during unit installation.
HORIZONTAL LEFT - 2 PIPE OPTION
Rubber
Grommet
Option
8
FLUE PIPE
Option
7
FLUE PIPE
HORIZONTAL RIGHT - 2 PIPE OPTION
Rubber
Grommet
COMBUSTION AIR
COMBUSTION AIR
See VIEW C for
drain line positions
Plug
See VIEW D for
drain line positions
Plug
Figure 27. Vent Pipe & Condensate Options - Horizontal Furnaces
37
Straps
or Other
Figure
28 Suitable
Supports at minimum of 5 ft. Intervals
HORIZONTAL VENTING
(2-Pipe Shown)
Seal/Caulk
Around Pipes
at Building
90°
Elbow
90°
Elbow
COMBUSTION AIR
See Table 2 for PVC Pipe
Lengths (Field Supplied)
Upward Pitch - 1/4” per foot
(Flue Pipe)
FLUE PIPE
Coupling with 2 Hose
Clamps (Optional)
90° Elbow
First support placed as close
to furnace connection as possible
12” Min.
7”
Wall
Normal
Snow Level
PVC Tee
PVC Trap
VERTICAL VENTING
(2-Pipe Shown)
Support System on
Vertical Rise
See Table 2 for PVC Pipe
Lengths (Field Supplied)
90° Elbow
(both ends)
COMBUSTION AIR
See Table 2 for PVC Pipe
Lengths (Field Supplied)
FLUE PIPE
Couplings with 2
Hose Clamps (Optional)
Support System on
Vertical Rise
FLUE PIPE
COMBUSTION AIR
First Support as Close
to Furnace as Possible
PVC Tee
PVC Trap
PVC Tee
PVC Trap
Figure 28. Horizontal & Vertical Venting Options
38
FURNACE COMPONENTS
The descriptions below are various functional components that affect the operation and shutting down of this furnace.
Some of these components and their locations are shown in Figure 30. If any component of the furnace must be
replaced, use only factory authorized replacement parts specified in the Replacement Parts List provided online.
Blower Limit Switch - The Blower switch prevents furnace operation when blower is not operational.
Condensate Drain Switch - The Condensate Drain Switch will shut down the furnace if the condensate drain from
the Collector Pan becomes clogged.
Flame Roll-Out Switch - The flame roll-out switch verifies that the burner flames are drawn into the heat exchanger
tubes. If the burner flames are not properly drawn into the heat exchanger, the flame roll-out switch will close the
gas valve and initiate the shutdown cycle.
Flame Sensor - The flame sensor verifies when a flame has carried over from the igniter to the opposite end burner.
If no flame is detected, the furnace will shut down within 4 seconds.
Gas Valve - The gas valve controls the flow of gas to the burners. When the gas valve is energized it automatically
opens and regulates the gas pressure in the manifold.
Inducer Assembly - The inducer assembly vents products of combustion to the outside.
Pressure Switch - Pressure switches verify that the inducer is drawing the combustion gases through the heat
exchanger. If the flame is not properly drawn into the heat exchanger tube, the rollout switch or the flame sensor
will shut the furnace down.
Supply Air Limit Switch - The supply air limit switch prevents the air temperature leaving the furnace from exceeding
the maximum allowable outlet air temperature.
Figure 29
Finish
Flange
Gas Manifold
Roll-Out
Switch
Burner
Assembly
Flame Sensor
Igniter
Pressure Switches
Main Air Limit Switch
Gas Valve
Inducer Limit Switch
Inducer Assembly
Furnace Control Board
Blower Door Switch
Transformer
Motor Control Box
Motor Choke
(C & D cabinets only)
Motor Control Board
Blower Assembly
Figure 29. *MQ Component Locations (Upflow & Horizontal)
39
INSTALLATION / PERFORMANCE CHECK LIST
ATTENTION INSTALLERS:
ELECTRICAL SYSTEM
It is your responsibility to know this product better than your customer.
This includes being able to install the product according to strict
safety guidelines and instructing the customer on how to operate
and maintain the equipment for the life of the product. Safety should
always be the deciding factor when installing this product and using common sense plays an important role as well. Pay attention to
all safety warnings and any other special notes highlighted in the
manual. Improper installation of the furnace or failure to follow safety
warnings could result in serious injury, death, or property damage.
These instructions are primarily intended to assist qualified individuals
experienced in the proper installation of this appliance. Some local
codes require licensed installation/service personnel for this type of
equipment. Please read all instructions carefully before starting the
installation. Return these instructions to the customer’s package for
future reference.
Electrical connections tight?
YES
NO
Line voltage polarity correct?
YES
NO
Supply Voltage:_________________________________ VOLTS
Has the thermostat been calibrated?
YES
NO
Is the thermostat level?
YES
NO
Is the heat anticipator setting correct?
YES
NO
Natural
Gas
Propane
YES
NO
GAS SYSTEM
Gas Type: (circle one)
Gas pipe connections leak tested?
INSTALLER NAME:
CITY:
Gas Line Pressure:_____________________________ (in - W.C.)
STATE:
Installation Altitude:_______________________________ (FT.)
INSTALLATION ADDRESS:
CITY:
Deration Percentage:_______________________________ (%)
STATE:
Furnace Input:__________________________________ (Btuh)
UNIT MODEL #
Supply Air Temperature: ___________________________ (° F)
UNIT SERIAL #
Return Air Temperature: ___________________________ (° F)
Minimum clearances as showni n
Figure 1, (page 6)?
YES
NO
Has the owner’s information been
reviewed with the home-owner?
YES
NO
Has the literature package been
left near the furnace?
YES
NO
Temperature Rise: ________________________________ (° F)
COMBUSTION AIR & VENTING SYSTEM
PROPOSITION 65 WARNING:
WARNING: This product contains chemicals known to
the state of California to cause cancer.
Is there adequate fresh air supply for
combustion and ventilation?
YES
NO
Vent free from restrictions?
YES
NO
Filter(s) secured in place?
YES
NO
Filter(s) clean?
YES
NO
Flue connections tight?
YES
NO
Is there proper draft?
YES
NO
WARNING: This product contains chemicals known to
the state of California to cause birth defects or other
reproductive harm.
Specifications & illustrations subject to change without notice or incurring obligations.
O’ Fallon, MO | Printed in U.S.A. (06/13)
709048D (Replaces 709048C)