Payne C Series Installation manual

PG8M/PG8J
Catalog No: 53PG-8J5 Form No. IM-PG8J-05 5-05
Installation, Start-up, Operating, and
Service and Maintenance Instructions
-Series C
The Payne PG8M/PG8J 80% AFUE Gas Furnaces feature 4-
way multipoise design and through-the-furnace downflow
venting. The PG8M/PG8J furnaces are approved for use with
natural or propane gas and the PG8J is also approved for use in
Low Nox Air Quality Management Districts.
STANDARD FEATURES
• Four-position furnace: upflow, horizontal right, horizontal
left, downflow
• Electronic control center
Adjustable heating air temperature rise
LED diagnostics and self test feature
• Hot surface ignition (HSI)
• Twinning in Upflow, Downflow and Horizontal
LIMITED WARRANTY
• 20-year warranty on “Super S™” heat exchanger
• 5-year parts warranty on all other components
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Single-Stage
Induced-Combustion
4-Way Multipoise Furnace
Installation, Start-up, Operating, and
Service and Maintenance Instructions
Series 120/C
NOTE: Read the entire instruction manual before starting the
installation.
This symbol →indicates a change since the last issue.
→Portions of the text and tables are reprinted from NFPA 54/ANSI Z223.1-2002©,
with permission of National Fire Protection Association, Quincy, MA 02269 and
American Gas Association, Washington DC 20001. This reprinted material is not the
complete and official position of the NFPA or ANSI on the referenced subject, which
is represented only by the standard in its entirety.
TABLE OF CONTENTS
SAFETY CONSIDERATIONS.....................................................2
INTRODUCTION..........................................................................4
CODES AND STANDARDS........................................................4
Safety.........................................................................................5
General Installation...................................................................5
Combustion and Ventilation Air..............................................5
Duct Systems ............................................................................5
Acoustical Lining and Fibrous Glass Duct..............................5
Gas Piping and Gas Pipe Pressure Testing..............................5
Electrical Connections..............................................................5
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS
PROCEDURE ................................................................................5
LOCATION....................................................................................5
General......................................................................................5
Location Relative to Cooling Equipment ................................7
AIR FOR COMBUSTION AND VENTILATION......................7
INSTALLATION.........................................................................10
Upflow Installation .................................................................10
Bottom Return Air Inlet....................................................10
Side Return Air Inlet.........................................................10
Leveling Legs (If Desired)................................................10
Downflow Installation ............................................................10
Bottom Return Air Inlet....................................................11
Horizontal Installation ............................................................11
Suspended Furnace Support..............................................11
Platform Furnace Support .................................................11
Roll-Out Protection............................................................11
Bottom Return Air Inlet....................................................11
Side Return Air Inlet.........................................................11
Filter Arrangement..................................................................11
Air Ducts.................................................................................11
General Requirements .......................................................11
Ductwork Acoustical Treatment .......................................12
Supply Air Connections....................................................12
Return Air Connections.....................................................14
Gas Piping...............................................................................15
Electrical Connections............................................................19
115-V Wiring.....................................................................19
J-Box Relocation ...............................................................20
Electrical Connection to J-Box.........................................21
Power Cord Installation in Furnace J-Box.......................21
BX Cable Installation in Furnace J-Box ..........................22
24-V Wiring.......................................................................22
Accessories ........................................................................22
Venting....................................................................................22
General Venting Requirements.........................................23
Masonry Chimney Requirements......................................23
Appliance Application Requirements ...............................24
Additional Venting Requirements.....................................26
Sidewall Venting ...............................................................26
START-UP, ADJUSTMENT, AND SAFETY CHECK............27
General....................................................................................27
Start-Up Procedures................................................................27
Adjustments.............................................................................31
Check Safety Controls............................................................34
Checklist..................................................................................35
SERVICE AND MAINTENANCE PROCEDURES..................35
Introduction.............................................................................35
General...............................................................................35
Electrical Controls and Wiring .........................................36
Care and Maintenance............................................................37
Cleaning and/or Replacing Air Filter ...............................37
Blower Motor and Wheel..................................................37
Cleaning Heat Exchanger..................................................40
Sequence of Operation............................................................44
Wiring Diagrams.....................................................................45
Troubleshooting ......................................................................45
Cancels: II 310A-45-4/IM-PG8J-04
II310A-45-5/IM-PG8J-05
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book 1 4
Tab 6a 8a PC 101 Catalog No. See Cover Printed in U.S.A. Form 58ST-13SI Pg 1 5-05 Replaces: 58ST-12SI

SAFETY CONSIDERATIONS
FIRE, EXPLOSION, ELECTRICAL SHOCK, AND
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in dangerous
operation, serious injury, death, or property damage.
Improper installation, adjustment, alteration, service, mainte-
nance, or use can cause carbon monoxide poisoning, explo-
sion, fire, electrical shock, or other conditions which may
cause personal injury or property damage. Consult a qualified
service agency, local gas supplier, or your distributor or
branch for information or assistance. The qualified service
agency must use only factory-authorized and listed kits or
accessories when modifying this product.
FURNACE RELIABILITY HAZARD
Improper installation or misapplication of furnace may re-
quire excessive servicing or cause premature component
failure.
Application of this furnace should be indoors with special
attention given to vent sizing and material, gas input rate, air
temperature rise, unit leveling, and unit sizing.
Installing and servicing heating equipment can be hazardous due to
gas and electrical components. Only trained and qualified
personnel should install, repair, or service heating equipment.
Untrained personnel can perform basic maintenance functions
such as cleaning and replacing air filters. All other operations must
be performed by trained service personnel. When working on
heating equipment, observe precautions in literature, on tags, and
on labels attached to or shipped with furnace and other safety
precautions that may apply.
These instructions cover minimum requirements and conform to
existing national standards and safety codes. In some instances,
these instructions exceed certain local codes and ordinances,
especially those that may not have kept up with changing residen-
tial construction practices. We require these instructions as a
minimum for a safe installation.
CUT HAZARD
Failure to follow this caution may result in personal injury.
Sheet metal parts may have sharp edges or burrs. Use care and
wear appropriate protective clothing, safety glasses and
gloves when handling parts and servicing furnaces.
Wear safety glasses and work gloves. Have fire extinguisher
available during start-up and adjustment procedures and service
calls.
This is the safety-alert symbol . When you see this symbol on
the furnace and in instructions or manuals, be alert to the potential
for personal injury.
Understand the signal words DANGER, WARNING, and CAU-
TION. These words are used with the safety-alert symbol. DAN-
GER identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies a hazard which
could result in personal injury or death. CAUTION is used to
identify hazards which may result in minor personal injury or
product and property damage. NOTE is used to highlight sugges-
tions which will result in enhanced installation, reliability, or
operation.
1. Use only with type of gas approved for this furnace. Refer to
the furnace rating plate.
2. Install this furnace only in a location and position as specified
in the “Location” section of these instructions.
NOTES:
1. Two additional 7/8-in. diameter holes are located in the top plate.
2. Minimum return-air openings ar furnace, based on metal duct. If flex duct is used, see flex duct manufacturer’s recommendations for equivalent diameters.
a. For 800 CFM-16-in. round or 14 1/2 x 12-in. rectangle.
b. For 1200 CFM-20-in. round or 14 1/2 x 19 1/2-in. rectangle.
c. For 1600 CFM-22-in. round or 14 1/2 x 22-in. rectangle.
d. For airflow requirements above 1800 CFM, see Air Delivery table in Product Data literature for specific
use of single side inlets. The use of both side inlets, a combination of 1 side and the bottom, or the
bottom only will ensure adequate return air openings for airflow requirements above 1800 CFM.
→Fig. 1—Dimensional Drawing
A04037
2-7/16"
1-1/8"
28-7/8"
25-1/4"
22-9/16"
JUNCTION BOX
LOCATION
7/8" DIA
ACCESSORY 1/2" DIA THERMOSTAT
WIRE ENTRY
3-15/16"
LEFT HAND GAS
ENTRY
33-5/16" 24-7/8"
5-1/2"
7/8" DIA. ACCESSORY
11/16"
21-5/8"
BOTTOM INLET 1-11/16"
13/16"
11/16"
4-13/16"
AIRFLOW
19"
OUTLET
13/16"
11/16"
8-9/16"
VENT OUTLET
5 PLACES (TYP)
3-3/4"
1-3/4" DIA.RIGHT HAND
GAS ENTRY
7/8" DIA. K.O. WIRE ENTRY
SIDE INLET
14-7/8"
7/8" DIA. ACCESSORY
1-1/4"
1"
22-1/16"
A
D
F
E
(FLUE COLLAR)
5-15/16"
24"
CASING
1-5/16"
1/2" DIA. K.O.THERMOSTAT
WIRE ENTRY
ALTERNATE
JUNCTION BOX
LOCATIONS (TYP)
26-1/8"
1-1/2"
7-3/4" 9-5/8"
11-1/2"
5-1/2"
2

→Fig. 2—Clearances to Combustibles
A04123
MINIMUM INCHES CLEARANCE TO COMBUSTIBLE CONSTRUCTION
DISTANCE MINIMALE EN POUCES AUX CONSTRUCTIONS COMBUSTIBLES
INSTALLATION
327590-101 REV. C
Ø
*
Clearance arrows
do not change with
furnace orientation.
BOTTOM
DESSOUS
0"
3"
0"
0"
1"
0"
24"
MIN
SIDE
CÔTÉ
FRONT
AVANT
BCK
ARRIÈ
A
E
R
SERVIE
C
ENTRT
EN
E
I
V
AN
AT
FRONT
SIE
CÔTÈ
FOU
U
FRNACS
EE
I
A
RN
Ø
TOP / PLENUM
DESSUS / CHAMBRED'AIR
D
*
*
†
MIN
Ø
*
†
This forced air furnace is equipped for use with
natural gas at altitudes 0-10,000 ft (0-3,050m).
An accessory kit, supplied by the
manufacturer, shall be used to convert to propane
gas use or may be required for some natural gas
applications.
This furnace is for indoor installation in a
building constructed on site.
This furnace may be installed on combustible
flooring in alcove or closet at minimum clearance
as indicated by the diagram from combusitble
material.
This furnace may be used with a Type B-1 Vent
and may be vented in common with other gas
fired appliances.
Cette fournaise à air pulsé est équipée
pour utilisation avec gaz naturel et altitudes
comprises entre 0-3,050m (0-10,000 pi).
Utiliser une trousse de conversion, fournie par
le fabricant, pour passer au gaz propane ou pour
certaines installations au gaz naturel.
Cette fournaise est prévue pour être
installée dans un bâtiment construit sur place.
Cette fournaise peut être installée sur
un plancher combustible dans une alcôve ou
dans un garde-robe en respectant le minimum
d'espace libre des matériaux combustibles, tel
qu
´ indiqué sur le diagramme.
Cette fournaise peut être utilisée avec un
conduit d
´ évacuation de Type B-1 ou connectée
au conduit ommun d 'autres appareils à gaz.
MINIMUM INCHES CLEARANCE TO COMBUSTIBLE CONSTRUCTION
Installation on non-combusibible floors only.
For Installation on combustible flooring only when installed on special base, Part No. KGASB0201ALL,
Coil Assembly, Part No. CD5 or CK5, or Coil Casing, Part No. KCAKC.
18 inches front clearance required for alcove.
Indicates supply or return sides when furnace is in the horizontal position. Line contact only permissible
between lines formed by intersections of the Top and two Sides of the furnace jacket, and building joists,
studs or framing.
DOWNFLOW POSITIONS:
DÉGAGEMENT MINIMUM EN POUCES AVEC ÉLÉMENTS
DE CONSTRUCTION COMBUSTIBLES
Pour l ´ installation sur plancher non combustible seulement.
Pour l ´ installation sur un plancher combustible seulement quand on utilise la base spéciale, pièce
nº KGASB0201ALL, l
´ ensemble serpentin, pièce nº CD5 ou CK5, ou le carter de serpentin, pièce
nº KCAKC.
Dans une alcôve, on doit maintenir un dégagement à l ´ avant de 18 po (450mm).
La poistion indiquée concerne le côté d
´ entrée ou de retour quand la fournaise est dans la
position horizontale.
Le contact n
´ est permis qu ´ entre les lignes formées par les intersections du dessus et des
deux côtés de la cherrise de la fournaise et les solives, montant sous cadre de charpente.
POUR LA POSITION COURANT DESCENDANT:
Cette fournaise est approuvée pour l 'installation HORIZONTALE
et la circulation d 'air VERS LE HAUT et VERS LE BAS.
This furnace is approved for UPFLOW, DOWNFLOW, and
HORIZONTAL installations.
Clearance in inches
Dégagement (po).
Les fléches de dégagement
ne change pas avec
l 'orientation de la fournaise.
Vent Clearance to combustibles:
For Single Wall vents 6 inches (6 po).
For Type B-1 vent type 1 inch (1 po).
Dégagement de l ´ évent avec combustibles:
Pour conduit d ´ évacuation à paroi simple 6 po (6 inches).
Pour conduit d
´ évacuation de Type B-1 1 po (1 inch).
†
3

3. Provide adequate combustion and ventilation air to the furnace
space as specified in “Air for Combustion and Ventilation”
section.
4. Combustion products must be discharged outdoors. Connect
this furnace to an approved vent system only, as specified in
the “Venting” section of these instructions.
5. Never test for gas leaks with an open flame. Use a commer-
cially available soap solution made specifically for the detec-
tion of leaks to check all connections, as specified in the “Gas
Piping” section.
6. Always install furnace to operate within the furnace’s intended
temperature-rise range with a duct system which has an
external static pressure within the allowable range, as speci-
fied in the “Start-Up, Adjustments, and Safety Check” section.
See furnace rating plate.
7. When a furnace is installed so that supply ducts carry air
circulated by the furnace to areas outside the space containing
the furnace, the return air shall also be handled by duct(s)
sealed to the furnace casing and terminating outside the space
containing the furnace. See “Air Ducts” section.
8. A gas-fired furnace for installation in a residential garage must
be installed as specified in the warning box in the “Location”
section.
9. The furnace is not to be used for temporary heating of
buildings or structures under construction. See page 7 caution
box regarding the heating of buildings under construction.
10. These Multipoise Gas-Fired Furnaces are CSA (formerly
A.G.A. and C.G.A.) design-certified for use with natural and
propane gases (see furnace rating plate) and for installation in
alcoves, attics, basements, closets, utility rooms, crawlspaces,
and garages. The furnace is factory-shipped for use with
natural gas. A CSA listed gas conversion kit is required to
convert furnace for use with propane gas.
11. See Fig. 2 for required clearances to combustible construction.
12. Maintain a 1-in. clearance from combustible materials to
supply air ductwork for a distance of 36 inches horizontally
from the furnace. See NFPA 90B or local code for further
requirements.
13. These furnaces SHALL NOT be installed directly on carpet-
ing, tile, or any other combustible material other than wood
flooring. In downflow installations, factory accessory floor
base MUST be used when installed on combustible materials
and wood flooring. Special base is not required when this
furnace is installed on manufacturer’s Coil Assembly Part No.
CD5 or CK5, or when Coil Box Part No. KCAKC is used. See
Fig. 2 for clearance to combustible construction information.
INTRODUCTION
This Series 120/C 4–way multipoise Category I fan-assisted
furnace is CSA design-certified. A Category I fan-assisted furnace
is an appliance equipped with an integral mechanical means to
either draw or force products of combustion through the combus-
tion chamber and/or heat exchanger. The furnace is factory-
shipped for use with natural gas. A CSA (A.G.A. and C.G.A.)
listed gas conversion kit is required to convert furnace for use with
propane gas. This furnace is not approved for installation in
mobile homes, recreational vehicles, or outdoors.
This furnace is designed for minimum continuous return-air
temperature of 60°F db or intermittent operation down to 55°F db
such as when used with a night setback thermostat. Return-air
temperature must not exceed 85°F db. Failure to follow these
return-air temperature limits may affect reliability of heat exchang-
ers, motors, and controls. (See Fig. 3.)
For accessory installation details, refer to the applicable instruction
literature.
NOTE: Remove all shipping brackets and materials before oper-
ating the furnace.
CODES AND STANDARDS
Follow all national and local codes and standards in addition to
these instructions. The installation must comply with regulations
of the serving gas supplier, local building, heating, plumbing, and
other codes. In absence of local codes, the installation must
comply with the national codes listed below and all authorities
having jurisdiction.
→Table 1—Dimensions (IN.)
FURNACE
SIZE A CABINET WIDTH
D
SUPPLY-AIR
WIDTH
(IN.)
E
RETURN-AIR
WIDTH
(IN.)
F
C.L. TOP AND
BOTTOM
FLUE COLLAR
(IN.)
FLUE
COLLAR*
(IN.) SHIP WT. (LB)
045-08/024045 14-3/16 12-9/16 12-11/16 9-5/16 4 104
045-12/036045 14-3/16 12-9/16 12-11/16 9-5/16 4 107
070-08/024070 14-3/16 12-9/16 12-11/16 9-5/16 4 111
070-12/036070 14-3/16 12-9/16 12-11/16 9-5/16 4 115
070-16/048070 17-1/2 15-7/8 16 11-9/16 4 126
090-14/042090 17-1/2 15-7/8 16 11-9/16 4 127
090-16/048090 21 19-3/8 19-1/2 13-5/16 4 140
090-20/060090 21 19-3/8 19-1/2 13-5/16 4 146
110-12/036110 17-1/2 15-7/8 16 11-9/16 4 135
110-16/048110 21 19-3/8 19-1/2 13-5/16 4 146
110-22/066110 21 19-3/8 19-1/2 13-5/16 4 152
135-16/048135 21 19-3/8 19-1/2 13-5/16 4 149
135-22/066135 24-1/2 22-7/8 23 15-1/16 4 163
155-20/060155 24-1/2 22-7/8 23 15-1/16 4 170
* 5” or 6” vent connector may be required in some cases.
4
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In the United States and Canada, follow all codes and standards for
the following:
Step 1—Safety
• US: National Fuel Gas Code (NFGC) NFPA 54–2002/ANSI
Z223.1–2002 and the Installation Standards, Warm Air Heating
and Air Conditioning Systems ANSI/NFPA 90B
• CANADA: CSA B149.1-00 National Standard of Canada
Natural Gas and Propane Installation Codes (NSCNGPIC)
Step 2—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 (www.NFPA.org); or
for only the NFGC, contact the American Gas Association, 400
N. Capitol Street, N.W., Washington, DC 20001
(www.AGA.org).
• CANADA: NSCNGPIC. For a copy, contact Standard Sales,
CSA International, 178 Rexdale Boulevard, Etobicoke (Tor-
onto), Ontario, M9W 1R3 Canada
Step 3—Combustion and Ventilation Air
• US: Section 8.3 of the NFGC, Air for Combustion and
Ventilation
• CANADA: Part 7 of NSCNGPIC, Venting Systems and Air
Supply for Appliances
Step 4—Duct Systems
• US and CANADA: Air Conditioning Contractors Association
(ACCA) Manual D, Sheet Metal and Air Conditioning Con-
tractors National Association (SMACNA), or American Soci-
ety of Heating, Refrigeration, and Air Conditioning Engineers
(ASHRAE) 2001 Fundamentals Handbook Chapter 34 or 2000
HVAC Systems and Equipment Handbook Chapters 9 and 16.
Step 5—Acoustical Lining and Fibrous Glass Duct
• US and CANADA: current edition of SMACNA and NFPA
90B as tested by UL Standard 181 for Class I Rigid Air Ducts
Step 6—Gas Piping and Gas Pipe Pressure Testing
• US: NFGC; chapters 5, 6, 7, and 12 and National Plumbing
Codes
• CANADA: NSCNGPIC Parts 3, 4, and 5, and Appendices A,
B, E and H.
Step 7—Electrical Connections
• US: National Electrical Code (NEC) ANSI/NFPA 70–2002
• CANADA: Canadian Electrical Code CSA C22.1
Step 8—Venting
• US: NFGC; chapters 10 and 13
• CANADA: NSCNGPIC Part 7 and Appendix C
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS
PROCEDURE
FURNACE RELIABILITY HAZARD
Improper installation or service of furnace may cause prema-
ture furnace component failure.
Electrostatic discharge can affect electronic components.
Take precautions during furnace installation and servicing to
protect the furnace electronic control. Precautions will pre-
vent electrostatic discharges from personnel and hand tools
which are held during the procedure. These precautions will
help to avoid exposing the control to electrostatic discharge
by putting the furnace, the control, and the person at the same
electrostatic potential.
1. Disconnect all power to the furnace. Multiple disconnects may
be required. DO NOT TOUCH THE CONTROL OR ANY
WIRE CONNECTED TO THE CONTROL PRIOR TO DIS-
CHARGING YOUR BODY’S ELECTROSTATIC CHARGE
TO GROUND.
2. Firmly touch the clean, unpainted, metal surface of the furnace
chassis which is close to the control. Tools held in a person’s
hand during grounding will be satisfactorily discharged.
3. After touching the chassis, you may proceed to service the
control or connecting wires as long as you do nothing to
recharge your body with static electricity (for example; DO
NOT move or shuffle your feet, do not touch ungrounded
objects, etc.).
4. If you touch ungrounded objects (and recharge your body with
static electricity), firmly touch a clean, unpainted metal
surface of the furnace again before touching control or wires.
5. Use this procedure for installed and uninstalled (ungrounded)
furnaces.
6. Before removing a new control from its container, discharge
your body’s electrostatic charge to ground to protect the
control from damage. If the control is to be installed in a
furnace, follow items 1 through 4 before bringing the control
or yourself in contact with the furnace. Put all used and new
controls into containers before touching ungrounded objects.
7. An ESD service kit (available from commercial sources) may
also be used to prevent ESD damage.
LOCATION
GENERAL
Some assembly and modifications are required when used in any
of the four applications shown in Fig. 4.
This furnace must:
• be installed so the electrical components are protected from
water.
•not be installed directly on any combustible material other than
wood flooring (refer to SAFETY CONSIDERATIONS).
• be located close to the chimney or vent and attached to an air
distribution system. Refer to Air Ducts section.
• be provided ample space for servicing and cleaning. Always
comply with minimum fire protection clearances shown on the
furnace clearance to combustible construction label.
Fig. 3—Return Air Temperature
A02055
60
5
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CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury
or death, and unit component damage.
Corrosive or contaminated air may cause failure of parts
containing flue gas, which could leak into the living space.
Air for combustion must not be contaminated by halogen
compounds, which include fluoride, chloride, bromide, and
iodide. These elements can corrode heat exchangers and
shorten furnace life. Air contaminants are found in aerosol
sprays, detergents, bleaches, cleaning solvents, salts, air
fresheners, and other household products. Do not install
furnace in a corrosive or contaminated atmosphere. Make
sure all combustion and circulating air requirements are met,
in addition to all local codes and ordinances.
The following types of furnace installations may require OUT-
DOOR AIR for combustion due to chemical exposures:
• Commercial buildings
• Buildings with indoor pools
• Laundry rooms
• Hobby or craft rooms, and
• Chemical storage areas
If air is exposed to the following substances, it should not be used
for combustion air, and outdoor air may be required for combus-
tion:
• Permanent wave solutions
• Chlorinated waxes and cleaners
• Chlorine based swimming pool chemicals
• Water softening chemicals
• De-icing salts or chemicals
• Carbon tetrachloride
• Halogen type refrigerants
• Cleaning solvents (such as perchloroethylene)
• Printing inks, paint removers, varnishes, etc.
• Hydrochloric acid
• Cements and glues
• Antistatic fabric softeners for clothes dryers
• Masonry acid washing materials
All fuel-burning equipment must be supplied with air for fuel
combustion. Sufficient air must be provided to avoid negative
pressure in the equipment room or space. A positive seal must be
made between the furnace cabinet and the return-air duct to
prevent pulling air from the burner area and from draft safeguard
opening.
FIRE, INJURY OR DEATH HAZARD
Improper location or inadequate protection could result in fire
or explosion.
When the furnace is installed in a residential garage, the
burners and ignition sources must be located at least 18 inches
above the floor. The furnace must be located or protected to
avoid damage by vehicles. When the furnace is installed in a
public garage, airplane hangar, or other building having a
hazardous atmosphere, the furnace must be installed in
accordance with the NFGC or NSCNGPIC. (See Fig. 5.)
Fig. 4—Multipoise Orientations
A02097
THE BLOWER IS LOCATED
TO THE RIGHT OF THE
BURNER SECTION, AND
AIR CONDITIONED AIR IS
DISCHARGED TO THE LEFT.
THE BLOWER IS
LOCATED BELOW THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED UPWARD.
THE BLOWER IS
LOCATED ABOVE THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED DOWNWARD
THE BLOWER IS
LOCATED TO THE LEFT
OF THE BURNER SECTION,
AND CONDITIONED AIR IS
DISCHARGEDTOTHE RIGHT.
Fig. 5—Installation in a Garage
A93044
18-IN. MINIMUM
TO BURNERS
6
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PERSONAL INJURY AND/OR PROPERTY DAMAGE
HAZARD
Improper use or installation of this furnace may cause
premature furnace component failure.
This gas furnace may be used for heating buildings under
construction provided that:
-The furnace is permanently installed with all electrical
wiring, piping, venting and ducting installed according to
these installation instructions. A return air duct is provided,
sealed to the furnace casing, and terminated outside the space
containing the furnace. This prevents a negative pressure
condition as created by the circulating air blower, causing a
flame rollout and/or drawing combustion products into the
structure.
-The furnace is controlled by a thermostat. It may not be ″hot
wired″to provide heat continuously to the structure without
thermostatic control.
-Clean outside air is provided for combustion. This is to
minimize the corrosive effects of adhesives, sealers and other
construction materials. It also prevents the entrainment of
drywall dust into combustion air, which can cause fouling
and plugging of furnace components.
-The temperature of the return air to the furnace is main-
tained between 55°F (13°C) and 80°F (27°C), with no
evening setback or shutdown. The use of the furnace while
the structure is under construction is deemed to be intermit-
tent operation per our installation instructions.
-The air temperature rise is within the rated rise range on the
furnace rating plate, and the firing rate has been set to the
nameplate value.
-The filters used to clean the circulating air during the
construction process must be either changed or thoroughly
cleaned prior to occupancy.
-The furnace, ductwork and filters are cleaned as necessary
to remove drywall dust and construction debris from all
HVAC system components after construction is completed.
-Verify proper furnace operating conditions including igni-
tion, gas input rate, air temperature rise, and venting
according to these installation instructions.
FIRE, INJURY OR DEATH HAZARD
Failure to follow this warning could result in unsafe furnace
operation.
DO NOT install the furnace on its back or hang furnace with
control compartment facing downward. Safety control opera-
tion will be adversely affected. Never connect return-air ducts
to back of furnace. (See Fig. 6.)
LOCATION RELATIVE TO COOLING EQUIPMENT
The cooling coil must be installed parallel with, or on the
downstream side of the unit to avoid condensation in the heat
exchangers. When installed parallel with the furnace, dampers or
other flow control must prevent chilled air from entering the
furnace. If the dampers are manually operated, they must be
equipped with means to prevent operation of either unit unless the
damper is in the full-heat or full-cool position.
AIR FOR COMBUSTION AND VENTILATION
Provisions for adequate combustion, ventilation, and dilution air
must be provided in accordance with:
•U.S. installations: Section 8.3 of the NFGC, Air for Combus-
tion and Ventilation, and applicable provisions of the local
building codes.
•Canadian installations: Part 7 of the NSCNGPIC, Venting
Systems and Air Supply for Appliances, and all authorities
having jurisdiction.
FURNACE CORROSION HAZARD
Failure to follow this caution may result in furnace damage.
Air for combustion must not be contaminated by halogen
compounds, which include fluoride, chloride, bromide, and
iodide. These elements can corrode heat exchangers and
shorten furnace life. Air contaminants are found in aerosol
sprays, detergents, bleaches, cleaning solvents, salts, air
fresheners, and other household products.
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury
or death.
The operation of exhaust fans, kitchen ventilation fans,
clothes dryers, attic exhaust fans or fireplaces could create a
NEGATIVE PRESSURE CONDITION at the furnace.
Make-up air MUST be provided for the ventilation devices, in
addition to that required by the furnace. Refer to Carbon
Monoxide Hazard warning in venting section of these instruc-
tions to determine if an adequate amount of make-up air is
available.
The requirements for combustion and ventilation air depend upon
whether or not the furnace is located in a space having a volume
of at least 50 cubic feet per 1,000 Btuh input rating for all gas
appliances installed in the space.
• Spaces having less than 50 cubic feet per 1,000 Btuh require
the OUTDOOR COMBUSTION AIR METHOD.
• Spaces having at least 50 cubic feet per 1,000 Btuh may use the
INDOOR COMBUSTION AIR, STANDARD or KNOWN-
AIR INFILTRATION METHOD.
Fig. 6—Prohibit Installation on Back
A02054
7
→
→
→
→
→

Outdoor Combustion Air Method
1. Provide the space with sufficient air for proper combustion,
ventilation, and dilution of flue gases using permanent hori-
zontal or vertical duct(s) or opening(s) directly communicat-
ing with the outdoors or spaces that freely communicate with
the outdoors.
2. Fig. 7 illustrates how to provide TWO OUTDOOR OPEN-
INGS, one inlet and one outlet combustion and ventilation air
opening, to the outdoors.
a. One opening MUST commence within 12″(300 mm) of
the ceiling and the second opening MUST commence
within 12″(300 mm) of the floor.
b. Size openings and ducts per Fig. 7 and Table 2.
c. TWO HORIZONTAL DUCTS require 1 square inch of
free area per 2,000 Btuh (1,100 mm
2
/kW) of combined
input for all gas appliances in the space per Fig. 7 and Table
2.
d. TWO OPENINGS OR VERTICAL DUCTS require 1
square inch of free area per 4,000 Btuh (550 mm
2
/kW) for
combined input of all gas appliances in the space per Fig.
7 and Table 2.
3. ONE OUTDOOR OPENING requires:
a. 1 square inch of free area per 3,000 Btuh (734 mm
2
/kW)
for combined input of all gas appliances in the space per
Table 2 and
b. Not less than the sum of the areas of all vent connectors in
the space.
The opening shall commence within 12″(300 mm) of the ceiling.
Appliances in the space shall have clearances of at least 1″(25
mm) from the sides and back and 6″(150 mm) from the front. The
opening shall directly communicate with the outdoors or shall
communicate through a vertical or horizontal duct to the outdoors
or spaces (crawl or attic) that freely communicate with the
outdoors.
Indoor Combustion Air© NFPA & AGA
Standard and Known-Air-Infiltration Rate Methods
Indoor air is permitted for combustion, ventilation, and dilution,
if the Standard or Known-Air-Infiltration Method is used.
CARBON MONOXIDE POISONING HAZARD
Failure to supply outdoor air via grilles or ducts could result
in death and/or personal injury.
Many homes require air to be supplied from outdoors for
furnace combustion, ventilation, and dilution of flue gases.
The furnace combustion air supply must be provided in
accordance with this instruction manual.
Table 2–Minimum Free Area Required for Each Combustion Air Opening or Duct to Outdoors
FURNACE
INPUT
(BTUH)
TWO HORIZONTAL DUCTS
(1 SQ. IN./2,000 BTUH) (1,100 SQ. MM/KW) SINGLE DUCT OR OPENING (1 SQ. IN./3,000 BTUH) (734 SQ. MM/KW) TWO OPENINGS OR VERTICAL DUCTS (1 SQ. IN./4,000 BTUH) (550 SQ. MM/KW)
Free Area of
Opening and Duct
(Sq. In.) Round Duct
(in. Dia) Free Area of
Opening and Duct
(sq In.) Round Duct
(in. Dia) Free Area of
Opening and Duct
(Sq In.) Round Duct
(In. Dia)
44,000 22 6 14.7 5 11 4
66,000 33 7 22 6 16.5 5
88,000 44 8 29.3 7 22 6
110,000 55 9 36.7 7 27.5 6
132,000 66 10 44 8 33 7
154,000 77 10 51.3 9 38.5 8
EXAMPLES: Determining Free Area
FURNACE WATER HEATER TOTAL INPUT
110,000 + 30,000 = (140,000 divided by 4,000) = 35.0 Sq. In. for each two Vertical Ducts or Openings
66,000 + 40,000 = (106,000 divided by 3,000) = 35.3 Sq. In. for a Single Duct or Opening
88,000 + 30,000 = (118,000 divided by 2,000) = 59.0 Sq. In. for each of two Horizontal Ducts
→Table 3–Minimum Space Volumes for 100% Combustion, Ventilation, and
Dilution from Indoors
ACH
OTHER THAN FAN-ASSISTED TOTAL
(1,000’S BTUH GAS INPUT RATE) FAN-ASSISTED TOTAL (1,000’S BTUH GAS INPUT RATE)
30 40 50 44 66 88 110 132 154
Space Volume (ft
3
)
0.60 1,050 1,400 1,750 1,100 1,650 2,200 2,750 3,300 3,850
0.50 1,260 1,680 2,100 1,320 1,980 2,640 3,300 3,960 4,620
0.40 1,575 2,100 2,625 1,650 2,475 3,300 4,125 4,950 5,775
0.30 2,100 2,800 3,500 2,200 3,300 4,400 5,500 6,600 7,700
0.20 3,150 4,200 5,250 3,300 4,950 6,600 8,250 9,900 11,550
0.10 6,300 8,400 10,500 6,600 9,900 13,200 16,500 19,800 23,100
0.00 NP NP NP NP NP NP NP NP NP
NP = Not Permitted
8
→
→
→

The Standard Method:
1. The space has no less volume than 50 cubic feet per 1,000
Btuh of the maximum input ratings for all gas appliances
installed in the space and
2. The air infiltration rate is not known to be less than 0.40 air
changes per hour (ACH).
The Known Air Infiltration Rate Method shall be used, if the
infiltration rate is known to be:
1. Less than 0.40 ACH and
2. Equal to or greater than 0.10 ACH
Infiltration rates greater than 0.60 ACH shall not be used. The
minimum required volume of the space varies with the number of
ACH and shall be determined per Table 3 or Equations 1 and 2.
Determine the minimum required volume for each appliance in the
space and add the volumes together to get the total minimum
required volume for the space.
Table 3-Minimum Space Volumes were determined by using the
following equations from the National Fuel Gas Code ANSI
Z223.1-2002/NFPA 54-2002,8.3.2.2:
1. For other than fan-assisted appliances, such as a draft
hood-equipped water heater:
2. For fan-assisted appliances such as this furnace:
If:I
other
= combined input of all other than fan-assisted appli-
ances in Btu/hr
I
fan
= combined input of all fan-assisted appliances in Btu/hr
ACH = air changes per hour (ACH shall not exceed 0.60.)
The following requirements apply to the Standard Method and to
the Known Air Infiltration Rate Method.
1. Adjoining rooms can be considered part of a space if:
a. There are no closable doors between rooms.
b. Combining spaces on same floor level. Each opening shall
have free area of at least 1 in.
2
/1,000 Btuh (2,000 mm
2
/kW)
of the total input rating of all gas appliances in the space,
but not less than 100 in.
2
(0.06 m
2
). One opening shall
commence within 12″(300 mm) of the ceiling and the
second opening shall commence within 12″(300 mm) of
the floor. The minimum dimension of air openings shall be
at least 3 in. (80 mm). (See Fig. 8.)
→Fig. 7—Air for Combustion, Ventilation and
Dilution for Outdoors
A03174
1 SQ IN.
PER
4000
BTUH*
DUCTS
TO
OUTDOORS
1 SQ IN.
PER 4000
BTUH*
CIRCULATING
AIR DUCTS
VENT
THROUGH
ROOF
D
B
A
C
E
1 SQ IN.
PER 4000
BTUH*
DUCT
TO
OUTDOORS
CIRCULATING AIR DUCTS
1 SQ IN.
PER 2000
BTUH*
1 SQ IN.
PER 2000
BTUH*
DUCTS
TO
OUTDOORS
12″MAX
12″MAX 12″MAX
Use any of the following
combinations of openings:
A & B C & D D & E F & G
NOTE:
*Minimum dimensions of 3 in.
12″
MAX
12″
MAX
OUTDOORS
1 SQ IN.
PER
4000
BTUH*
F
G
CLEARANCE IN FRONT
OF COMBUSTION AIR
OPENINGS SHALL BE
AT LEAST 3 IN.
A04002
VolumeOther =21ft3
ACH I other 1000 Btu/hr
→Fig. 8—Air for Combustion, Ventilation and
Dilution from Indoors
A03175
CIRCULATING AIR
DUCTS
6" MIN
(FRONT)†
CIRCULATING AIR DUCTS
VENT THROUGH ROOF
1 SQ IN.
PER 1000
BTUH* IN DOOR
ORWALL
12" MAX
1 SQ IN.
PER 1000
BTUH* IN DOOR
ORWALL
12" MAX
* Minimum opening size is 100 sq in. with
minimum dimensions of 3 in.
†Minimum of 3 in.. when type-B1 vent is used.
UNCONFINED
SPACE
INTERIOR
HEATED
SPACE
CLEARANCE IN FRONT OF COMBUSTION AIR
OPENINGS SHALL BE AT LEAST3 IN.
A04003
VolumeFan =15ft3
ACH I fan 1000 Btu/hr
9
→

c. Combining space on different floor levels. The volumes of
spaces on different floor levels shall be considered as
communicating spaces if connected by one or more perma-
nent openings in doors or floors having free area of at least
2 in.
2
/1,000 Btuh (4,400 mm
2
/kW) of total input rating of
all gas appliances.
2. An attic or crawlspace may be considered a space that freely
communicates with the outdoors provided there are adequate
permanent ventilation openings directly to outdoors having
free area of at least 1-in.
2
/4,000 Btuh of total input rating for
all gas appliances in the space.
3. In spaces that use the Indoor Combustion Air Method,
infiltration should be adequate to provide air for combustion,
permanent ventilation and dilution of flue gases. However, in
buildings with unusually tight construction, additional air
MUST be provided using the methods described in the
Outdoor Combustion Air Method section.
Unusually tight construction is defined as
Construction with:
a. Walls and ceilings exposed to the outdoors have a continu-
ous, sealed vapor barrier. Openings are gasketed or sealed
and
b. Doors and openable windows are weatherstripped and
c. Other openings are caulked or sealed. These include joints
around window and door frames, between sole plates and
floors, between wall-ceiling joints, between wall panels, at
penetrations for plumbing, electrical and gas lines, etc.
Combination of Indoor and Outdoor Air
1. Indoor openings shall comply with the Indoor Combustion
Air Method below and,
2. Outdoor openings shall be located as required in the Outdoor
Combustion Air Method mentioned previously and,
3. Outdoor openings shall be sized as follows:
a. Calculate the Ratio of all Indoor Space volume divided by
required volume for Indoor Combustion Air Method
below.
b. Outdoor opening size reduction Factor is 1 minus the
Ratio in a. above.
c. Minimum size of Outdoor openings shall be the size
required in Outdoor Combustion Air Method above
multiplied by reduction Factor in b. above. The minimum
dimension of air openings shall be not less than 3 in. (80
mm).
INSTALLATION
UPFLOW INSTALLATION
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return-air opening. Remove and discard this panel when
bottom return air is used. To remove bottom closure panel,
perform the following:
1. Tilt or raise furnace and remove 2 screws holding bottom filler
panel. (See Fig. 9.)
2. Rotate bottom filler panel downward to release holding tabs.
3. Remove bottom closure panel.
4. Reinstall bottom filler panel and screws.
Side Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return-air opening. This panel MUST be in place when
only side return air is used.
NOTE: Side return-air openings can be used in UPFLOW and
most HORIZONTAL configurations. Do not use side return-air
openings in DOWNFLOW configuration.
Leveling Legs (If Desired)
In upflow position with side return inlet(s), leveling legs may be
used. (See Fig. 10.) Install field-supplied, 5/16 X 1-1/2 in. (max)
corrosion-resistant machine bolts, washers and nuts.
NOTE: Bottom closure must be used when leveling legs are used.
It may be necessary to remove and reinstall bottom closure panel
to install leveling legs. To remove bottom closure panel, see Item
1. in Bottom Return Air Inlet section.
To install leveling legs:
1. Position furnace on its back. Locate and drill a hole in each
bottom corner of furnace. (See Fig. 10.)
2. For each leg, install nut on bolt and then install bolt and nut in
hole. (Install flat washer if desired.)
3. Install another nut on other side of furnace base. (Install flat
washer if desired.)
4. Adjust outside nut to provide desired height, and tighten inside
nut to secure arrangement.
5. Reinstall bottom closure panel if removed.
DOWNFLOW INSTALLATION
NOTE: For downflow applications, this furnace is approved for
use on combustible flooring when any one of the following 3
accessories are used:
• Special Base, KGASB
• Cased Coil Assembly Part No. CD5 or CK5
• Coil Box Part No. KCAKC
1. Determine application being installed from Table 3.
2. Construct hole in floor per Table 3 and Fig. 11.
3. Construct plenum to dimensions specified in Table 3 and Fig.
11.
4. If downflow subbase, KGASB is used, install as shown in Fig.
12. If Coil Assembly Part No. CD5 or CK5 or Coil Box Part
No. KCAKC is used, install as shown in Fig. 13.
NOTE: It is recommended that the perforated supply-air duct
flanges be completely folded over or removed from furnace when
installing the furnace on a factory-supplied cased coil or coil box.
To remove the supply-air duct flange, use wide duct pliers or hand
seamers to bend flange back and forth until it breaks off. Be careful
of sharp edges. (See Fig. 14.)
Fig. 9—Removing Bottom Closure Panel
A02098
10
→

Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return-air opening. Remove and discard this panel when
bottom return air is used. To remove bottom closure panel,
perform the following:
1. Tilt or raise furnace and remove 2 screws holding bottom filler
panel. (See Fig. 9.)
2. Rotate bottom filler panel downward to release holding tabs.
3. Remove bottom closure panel.
4. Reinstall bottom filler panel and screws.
HORIZONTAL INSTALLATION
FIRE, EXPLOSION, AND CARBON MONOXIDE
POISONING HAZARD
Failure to follow this warning could result in dangerous
operation, serious injury, death or property damage.
Do not install the furnace on its back or hang furnace with
control compartment facing downward. Safety control opera-
tion will be adversely affected. Never connect return-air ducts
to the back of the furnace.
The furnace can be installed horizontally in an attic or crawl space
on either the left-hand (LH) or right-hand (RH) side. The furnace
can be hung from floor joists, rafters or trusses or installed on a
non-combustible platform, blocks, bricks or pad.
Suspended Furnace Support
The furnace may be supported under each end with threaded rod,
angle iron or metal plumber’s strap as shown. (See Fig. 15 and 16.)
Secure angle iron to bottom of furnace as shown. Heavy-gauge
sheet metal straps (plumber’s straps) may be used to suspend the
furnace from each bottom corner. To prevent screws from pulling
out, use 2 #8 x ¾-in. screws into the side and 2 #8 x ¾-in. screws
in the bottom of the furnace casing for each strap. (See Fig. 15 and
16.)
If the screws are attached to ONLY the furnace sides and not the
bottom, the straps must be vertical against the furnace sides and
not pull away from the furnace sides, so that the strap attachment
screws are not in tension (are loaded in shear) for reliable support.
Platform Furnace Support
Construct working platform at location where all required furnace
clearances are met. (See Fig. 2 and 17.) For furnaces with 1-in.
clearance requirement on side, set furnace on non-combustible
blocks, bricks or angle iron. For crawlspace installations, if the
furnace is not suspended from the floor joists, the ground under-
neath furnace must be level and the furnace set on blocks or bricks.
Roll-Out Protection
Provide a minimum 17-3/4″X22″piece of sheet metal for flame
roll-out protection in front of burner area for furnaces closer than
12 inches above the combustible deck or suspended furnaces
closer than 12-in. to joists. The sheet metal MUST extend
underneath the furnace casing by 1 in. with the door removed.
The bottom closure panel on furnaces of widths 17-1/2 in. and
larger may be used for flame roll-out protection when bottom of
furnace is used for return air connection. See Fig. 17 for proper
orientation of roll-out shield.
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return-air opening. Remove and discard this panel when
bottom return air is used. To remove bottom closure panel,
perform the following:
1. Tilt or raise furnace and remove 2 screws holding bottom filler
panel. (See Fig. 9.)
2. Rotate bottom filler panel downward to release holding tabs.
3. Remove bottom closure panel.
4. Reinstall bottom filler panel and screws.
Side Return Air Inlet
These furnaces are shipped with bottom closure panel installed in
bottom return-air opening. This panel MUST be in place when side
return air inlet(s) is used without a bottom return air linlet.
Not all horizontal furnaces are approved for side return air
connections (See Fig. 20.)
FILTER ARRANGEMENT
FIRE, CARBON MONOXIDE AND POISONING
HAZARD
Failure to follow this warning could result in fire, personal
injury, or death.
Never operate a furnace without a filter or with filter access
door removed.
There are no provisions for an internal filter rack in these furnaces.
A field-supplied accessory external filter rack is required.
This furnace requires KGAFR0301ALL 1″external filter rack or a
suitable field-supplied substitute, such as the Media Cabinet.
Refer to the instructions supplied with external filter rack for
assembly and installation options.
AIR DUCTS
General Requirements
The duct system should be designed and sized according to
accepted national standards such as those published by: Air
Conditioning Contractors Association (ACCA), Sheet Metal and
Air Conditioning Contractors National Association (SMACNA) or
American Society of Heating, Refrigerating and Air Conditioning
Engineers (ASHRAE) or consult The Air Systems Design Guide-
lines reference tables available from your local distributor. The
duct system should be sized to handle the required system design
Fig. 10—Leveling Legs
A02071
1 3⁄4″
1 3⁄4″
1 3⁄4″
1 3⁄4″
5⁄16″
5⁄16″
5⁄16″
5⁄16″
11
→
→

CFM at the design external static pressure. The furnace airflow
rates are provided in Table 5-AIR DELIVERY-CFM (With Filter).
When a furnace is installed so that the supply ducts carry air
circulated by the furnace to areas outside the space containing the
furnace, the return air shall also be handled by a duct(s) sealed to
the furnace casing and terminating outside the space containing the
furnace.
Secure ductwork with proper fasteners for type of ductwork used.
Seal supply- and return-duct connections to furnace with code
approved tape or duct sealer.
NOTE: Flexible connections should be used between ductwork
and furnace to prevent transmission of vibration. Ductwork pass-
ing through unconditioned space should be insulated and sealed to
enhance system performance. When air conditioning is used, a
vapor barrier is recommended.
Maintain a 1-in. clearance from combustible materials to supply air
ductwork for a distance of 36 in. horizontally from the furnace. See
NFPA 90B or local code for further requirements.
Ductwork Acoustical Treatment
NOTE: Metal duct systems that do not have a 90 degree elbow
and 10 ft of main duct to the first branch take-off may require
internal acoustical lining. As an alternative, fibrous ductwork may
be used if constructed and installed in accordance with the latest
edition of SMACNA construction standard on fibrous glass ducts.
Both acoustical lining and fibrous ductwork shall comply with
NFPA 90B as tested by UL Standard 181 for Class 1 Rigid air
ducts.
Supply Air Connections
For a furnace not equipped with a cooling coil, the outlet duct shall
be provided with a removable access panel. This opening shall be
accessible when the furnace is installed and shall be of such a size
that the heat exchanger can be viewed for possible openings using
light assistance or a probe can be inserted for sampling the air
stream. The cover attachment shall prevent leaks.
Upflow and Horizontal Furnaces
Connect supply-air duct to flange on furnace supply-air outlet.
Bend flange upward to 90° with wide duct pliers. (See Fig. 14.)
The supply-air duct must be connected to ONLY the furnace
supply-outlet-air duct flanges or air conditioning coil casing (when
used). DO NOT cut main furnace casing side to attach supply air
duct, humidifier, or other accessories. All accessories MUST be
connected external to furnace main casing.
NOTE: For horizontal applications, the top-most flange may be
bent past 90 degrees to allow the evaporator coil to hang on the
flange temporarily while the remaining attachment and sealing of
the coil are performed.
Table 4—Opening Dimensions (In.)
FURNACE
CASING
WIDTH APPLICATION PLENUM OPENING FLOOR OPENING
ABCD
14–3/16
Upflow Applications on Combustible or Noncombustible
Flooring (KGASB subbase not required) 12-11/16 21-5/8 13-5/16 22-1/4
Downflow Applications on Noncombustible Flooring
(KGASB subbase not required) 12-9/16 19 13-3/16 19-5/8
Downflow applications on combustible flooring (KGASB
subbase required) 11-13/16 19 13-7/16 20-5/8
Downflow Applications on Combustible Flooring with CD5 or
CK5 Coil Assembly or KCAKC coil box (KGASB subbase
not required) 12-5/16 19 13-5/16 20
17–1/2
Upflow Applications on Combustible or Noncombustible
Flooring (KGASB subbase not required) 16 21-5/8 16-5/8 22-1/4
Downflow Applications on Noncombustible Flooring
(KGASB subbase not required) 15-7/8 19 16-1/2 19-5/8
Downflow applications on combustible flooring (KGASB
subbase required) 15-1/8 19 16-3/4 20-5/8
Downflow Applications on Combustible Flooring with CD5 or
CK5 Coil Assembly or KCAKC coil box (KGASB subbase
not required) 15-1/2 19 16-1/2 20
21
Upflow Applications on Combustible or Noncombustible
Flooring (KGASB subbase not required) 19-1/2 21-5/8 20-1/8 22-1/4
Downflow Applications on Noncombustible Flooring
(KGASB subbase not required) 19-3/8 19 20 19-5/8
Downflow applications on combustible flooring (KGASB
subbase required) 18-5/8 19 20-1/4 20-5/8
Downflow Applications on Combustible Flooring with CD5 or
CK5 Coil Assembly or KCAKC coil box (KGASB subbase
not required) 19 19 20 20
24-1/2
Upflow Applications on Combustible or Noncombustible
Flooring (KGASB subbase not required) 23 21-1/8 23-5/8 22-1/4
Downflow Applications on Noncombustible Flooring
(KGASB subbase not required) 22-7/8 19 23-1/2 19-5/8
Downflow applications on Combustible flooring (KGASB
subbase required) 22-1/8 19 23-3/4 20-5/8
Downflow Applications on Combustible Flooring with CD5 or
CK5 Coil Assembly or KCAKC coil box (KGASB subbase
not required) 22-1/2 19 23-1/2 20
12
→

Downflow Furnaces
Connect supply-air duct to supply-air outlet on furnace. Bend
flange inward past 90° with wide duct pliers. (See Fig. 14.) The
supply-air duct must be connected to ONLY the furnace supply-
outlet or air conditioning coil casing (when used). When installed
on combustible material, supply-air duct must be connected to
ONLY the accessory subbase, KGASB0201ALL, or factory ap-
proved air conditioning coil casing. DO NOT cut main furnace
casing to attach supply side air duct, humidifier, or other accesso-
ries. All accessories MUST be connected external to furnace
casing.
PLENUM
OPENING
C
A
BD
FLOOR
OPENING
A96283
Fig. 11—Floor and Plenum Opening Dimensions
A04140
CD5 OR CK5
COIL ASSEMBLY
OR KCAKC
COIL BOX
FURNACE
SHEET METAL
PLENUM
FLOOR
OPENING
COMBUSTIBLE
FLOORING
Fig. 13—Furnace, Plenum, and Coil Assembly or Coil Box Installed on a Combustible Floor
DOWNFLOW
SUBBASE
SHEET METAL
PLENUM
FLOOR
OPENING
FURNACE
(OR COIL CASING
WHEN USED)
COMBUSTIBLE
FLOORING
A96285
Fig. 12—Furnace, Plenum, and Subbase Installed on
a Combustible Floor
13
→

Return Air Connections
FIRE HAZARD
Failure to follow this warning could cause a fire, personal
injury, or death.
Never connect return-air ducts to the back of the furnace.
Follow instructions below.
Downflow Furnaces
The return-air duct must be connected to return-air opening
(bottom inlet) as shown in Fig. 19. DO NOT cut into casing sides
(left or right). Side opening is permitted for only upflow and most
horizontal furnaces. Bypass humidifier connections should be
made at ductwork or coil casing sides exterior to furnace.
Upflow and Horizontal Furnaces
The return-air duct must be connected to bottom, sides (left or
right), or a combination of bottom and side(s) of main furnace
casing as shown in Fig. 18 and 20. Bypass humidifier may be
attached to unused side return air side of the furnace casing. (See
Fig. 18 and 20.)
Not all horizontal furnaces are approved for side return air
connections. (See Fig. 20.)
Fig. 14—Duct Flanges A02329
UPFLOW OWNFLOW HORIZONTAL
PREFERRED
PERMITTED
PREFERRED
PREFERRED
PREFERRED
120˚
MIN PREFERRED 120˚
MIN PREFERRED
120˚
MIN
90˚ 90˚
PERMITTED PERMITTED
D
→Fig. 15—Horizontal Unit Suspension
A05027
1/4" THREADED ROD
4 REQ.
SECURE ANGLE
IRON TO BOTTOM
OF FURNACE WITH
3 #8 x 3/4" SCREWS
TYPICAL FOR 2 SUPPORTS
1" SQUARE, 11/4" x 11/4" x 1/8" ANGLE IRON
OR UNI-STRUT MAY BE USED
(2) HEX NUTS, (2) WASHERS & (2) LOCK WASHERS
REQ. PER ROD
8" MIN FOR DOOR
REMOVAL
OUTER DOOR
ASSEMBLY
14

GAS PIPING
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in personal injury,
death and/or property damage.
Never purge a gas line into a combustion chamber. Never test
for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection of
leaks to check all connections.
FIRE OR EXPLOSION HAZARD
Failure to follow this warning coud result in personal injury,
death, and/or property damage.
Use proper length of pipe to avoid stress on gas control
manifold and a gas leak.
Gas piping must be installed in accordance with national and local
codes. Refer to current edition of NFGC in the U.S., the NSCNG-
PIC in Canada.
Fig. 16—Horizontal Suspension with Straps
A02014
Fig. 17—Typical Attic Installation
A02164
30-IN. MIN
WORK AREA
6″ MIN*
TYPE-B
VENT
17 3/4 ″
22 ″
SHEET
METAL
SEDIMENT
TRAP
MANUAL SHUTOFF
GAS VALVE
LINE CONTACT ONLY PERMISSIBLE BETWEEN
LINES FORMED BY INTERSECTIONS OF
THE TOP AND TWO SIDES OFTHE FURNACE
JACKET AND BUILDING JOISTS,
STUDS, OR FRAMING.
GAS
ENTRY
17 3/4 ″ OVER ALL
4 3/4 ″ UNDER DOOR
1″UNDER FURNACE
EXTEND OUT 12″ OUT
FROM FACE OF DOOR
* WHEN USED WITH
SINGLE WALL VENT
CONNECTIONS
15
→

Table 5—Air Delivery - CFM (With Filter)*
FURNACE
SIZE RETURN-AIR INLET SPEED EXTERNAL STATIC PRESSURE (IN. WC)
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
024045 Bottom or
Side(s)
High
Med-High
Med-Low
1085
920
820
1035
875
775
975
830
730
915
770
680
845
710
620
770
640
555
675
555
470
565
440
360
390
250
190
195
--
--
036045 Bottom or
Side(s)
High
Med-High
Med-Low
1440
1360
1250
1375
1300
1210
1305
1240
1160
1240
1175
1100
1160
1115
1040
1070
1040
965
975
950
885
870
850
790
730
725
670
560
575
520
024070 Bottom or
Side(s)
High
Med-High
Med-Low
1030
835
725
1010
815
700
980
790
675
945
760
645
900
720
600
845
675
555
775
610
475
680
490
390
490
375
300
335
265
--
036070 Bottom or
Side(s)
High
Med-High
Med-Low
1425
1320
1200
1375
1280
1175
1320
1240
1145
1265
1205
1105
1200
1140
1050
1125
1075
990
1035
995
920
940
905
840
830
790
725
655
620
555
048070 Bottom or
Side(s)
High
Med-High
Med-Low
1805
1630
1460
1740
1585
1420
1670
1530
1385
1600
1470
1325
1530
1405
1280
1445
1330
1220
1360
1255
1155
1280
1170
1080
1180
1080
995
1075
990
910
042090 Bottom or
Side(s)
High
Med-High
Med-Low
1650
1515
1385
1600
1485
1360
1535
1440
1320
1465
1380
1260
1385
1300
1195
1285
1220
1120
1175
1115
1025
1055
990
915
895
830
710
645
600
565
048090 Bottom or
Side(s)
High
Med-High
Med-Low
2060
1790
1505
1985
1765
1505
1915
1715
1480
1820
1645
1440
1720
1560
1375
1610
1470
1300
1490
1345
1190
1340
1195
1045
1135
1010
890
925
820
740
060090
Bottom
Only High
Med-High
Med-Low
2405
2225
2020
2310
2155
1955
2220
2080
1880
2130
1995
1805
2025
1895
1730
1920
1785
1630
1790
1675
1535
1660
1565
1420
1530
1420
1275
1350
1260
1135
Both Sides or
1 Side & Bottom High
Med-High
Med-Low
2530
2285
1995
2450
2215
1945
2365
2150
1900
2270
2075
1840
2165
1985
1770
2065
1890
1685
1940
1780
1600
1805
1660
1480
1670
1525
1350
1505
1360
1180
1 Side Only High Med-High
Med-Low
2475
2260
1950
2395
2190
1910
2300
2110
1855
2200
2035
1795
2090
1940
1730
1985
1845
1650
1865
1735
1555
1730
1620
1445
1585
1475
1310
1425
1325
1150
036110 Bottom or
Side(s)
High
Med-High
Med-Low
1625
1510
1360
1575
1470
1335
1515
1415
1295
1445
1355
1250
1355
1285
1180
1260
1185
1100
1165
1070
985
990
890
810
785
725
--
--
--
--
048110 Bottom or
Side(s)
High
Med-High
Med-Low
2035
1745
1530
1965
1710
1515
1880
1650
1470
1790
1560
1400
1680
1450
1310
1495
1340
1215
1365
1205
1095
1215
1090
990
1075
955
830
875
750
670
066110
Bottom
Only High
Med-High
Med-Low
2530
2230
1920
2470
2205
1900
2400
2165
1880
2320
2110
1845
2220
2035
1795
2115
1950
1730
2000
1855
1650
1865
1740
1555
1730
1615
1460
1590
1485
1340
Bottom Sides or
1 Side & Bottom High
Med-High
Med-Low
--
2235
1920
--
2200
1900
2415
2155
1880
2350
2100
1845
2250
2040
1795
2145
1955
1730
2015
1850
1650
1875
1740
1555
1715
1595
1460
1560
1470
1340
1 Side Only High Med-High
Med-Low 2540
2125 2495
2120
1795
2430
2105
1790
2355
2060
1765
2265
2010
1720
2175
1940
1650
2065
1840
1585
1935
1730
1500
1785
1615
1390
1650
1485
1280
*A filter is required for each return-air inlet. Airflow performance included 1-in. washable filter media such as contained in factory-authorized accessory filter rack. To
determine airflow performance without this filter, assume an additional 0.1 in. wc available external static pressure.
-- Indicates unstable operating conditions.
16
→

Installations must be made in accordance with all authorities
having jurisdiction. If possible, the gas supply line should be a
separate line running directly from meter to furnace.
NOTE: In the state of Massachusetts:
1. Gas supply connections MUST be performed by a licensed
plumber or gas fitter.
2. When flexible connectors are used, the maximum length
shall not exceed 36 inches (915 mm).
3. When lever handle type manual equipment shutoff valves are
used, they shall be T-handle valves.
4. The use of copper tubing for gas piping is NOT approved by
the state of Massachusetts.
Refer to Table 6 for recommended gas pipe sizing. Risers must be
used to connect to furnace and to meter. Support all gas piping
with appropriate straps, hangers, etc. Use a minimum of 1 hanger
every 6 ft. Joint compound (pipe dope) should be applied sparingly
and only to male threads of joints. Pipe dope must be resistant to
the action of propane gas.
FIRE OR EXPLOSION HAZARD
Failure to follow this warning could result in death, personal
injury and/or property damage.
If local codes allow the use of a flexible gas appliance
connector, always use a new listed connector. Do not use a
connector which has previously served another gas appliance.
Black iron pipe shall be installed at the furnace gas control
valve and extend a minimum of 2-in. outside the furnace.
FURNACE OVERHEAT HAZARD
Failure to follow this caution may result in property damage.
Connect gas pipe to gas valve using a backup wrench to avoid
damaging gas controls.
An accessible manual equipment shutoff valve MUST be installed
external to furnace casing and within 6 ft of furnace. A 1/8-in. NPT
plugged tapping, accessible for test gauge connection, MUST be
installed immediately upstream of gas supply connection to
furnace and downstream of manual equipment shutoff valve.
NOTE: The gas valve inlet pressure tap connection is suitable to
use as test gauge connection providing test pressure DOES NOT
exceed maximum 0.5 psig (14-in. wc) stated on gas control valve.
(See Fig. 46.)
Some installations require gas entry on right side of furnace (as
viewed in upflow). (See Fig. 21a.)
Install a sediment trap in riser leading to furnace as shown in Fig
21b. Connect a capped nipple into lower end of tee. Capped nipple
should extend below level of furnace gas controls. Place a ground
joint union between furnace gas control valve and exterior manual
equipment gas shutoff valve. A 1/8-in. NPT plugged tapping,
accessible for test gauge connection, MUST be installed immedi-
ately upstream of gas supply connection to furnace and down-
stream of manual equipment shutoff valve.
Piping should be pressure and leak tested in accordance with
NFGC in the United States or NSCNGPIC in Canada, local, and
national plumbing and gas codes before the furnace has been
connected. After all connections have been made, purge lines and
check for leakage at furnace prior to operating furnace.
If pressure exceeds 0.5 psig (14-in. wc), gas supply pipe must be
disconnected from furnace and capped before and during supply
pipe pressure test. If test pressure is equal to or less than 0.5 psig
(14-in. wc), turn off electric shutoff switch located on furnace gas
control valve and accessible manual equipment shutoff valve
before and during supply pipe pressure test. After all connections
have been made, purge lines and check for leakage at furnace prior
to operating furnace.
The gas supply pressure shall be within the maximum and
minimum inlet supply pressures marked on the rating plate with
the furnace burners ON and OFF.
Table 5—Air Delivery - CFM (With Filter)* (Continued)
FURNACE
SIZE RETURN-AIR INLET SPEED EXTERNAL STATIC PRESSURE (IN. WC)
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0
048135 Bottom or
Side(s)
High
Med-High
Med-Low
2090
1790
1545
2010
1755
1525
1930
1705
1500
1835
1640
1450
1710
1550
1380
1590
1465
1315
1470
1360
1215
1335
1210
1005
1025
945
855
835
785
670
066135
Bottom
Only High
Med-High
Med-Low
2485
2195
1880
2400
2150
1850
2310
2090
1820
2215
2000
1780
2110
1920
1715
2000
1825
1635
1880
1720
1540
1725
1565
1415
1535
1405
1290
1355
1255
1160
Bottom, Sides or
1 Side & Bottom High
Med-High
Med-Low
--
2180
1880
--
2145
1850
2385
2060
1820
2305
2010
1780
2195
1945
1715
2085
1865
1635
1960
1765
1540
1825
1660
1415
1670
1515
1290
1465
1325
1160
1 Side Only High Med-High
Med-Low
--
2135
1880
--
2085
1850
2245
2035
1820
2155
1975
1780
2055
1895
1715
1940
1795
1635
1825
1685
1540
1695
1565
1415
1555
1445
1290
1385
1265
1160
060155
Bottom
Only High
Med-High
Med-Low
2465
2115
1800
2430
2105
1790
2375
2075
1770
2305
2030
1735
2230
1980
1695
2110
1910
1640
2000
1830
1570
1865
1725
1465
1725
1590
1345
1545
1425
1225
Both Sides Or
1 Side & Bottom High
Med-High
Med-Low
--
2155
1800
--
2135
1790
2375
2095
1770
2285
2040
1735
2200
1975
1695
2105
1895
1640
1995
1790
1570
1870
1685
1465
1730
1550
1345
1570
1400
1225
1 Side Only High Med-High
Med-Low
--
2140
1800
--
2095
1790
2260
2040
1770
2180
1975
1735
2085
1890
1695
1975
1810
1640
1865
1705
1570
1740
1595
1465
1605
1480
1345
1455
1325
1225
*A filter is required for each return-air inlet. Airflow performance included 1-in. washable filter media such as contained in factory-authorized accessory filter rack. To
determine airflow performance without this filter, assume an additional 0.1 in. wc available external static pressure.
-- Indicates unstable operating conditions.
17
→
→
→
→
→

A02075
Fig. 18—Upflow Return Air Configurations and Restrictions
A02163
Fig. 19—Downflow Return Air Configurations and Restrictions
A02162
Fig. 20—Horizontal Return Air Configurations and Restrictions
18

ELECTRICAL CONNECTIONS
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in serious personal
injury or death.
Blower access panel door switch opens 115-v power to
control. No component operation can occur. Do not bypass or
close switch with panel removed.
See Fig. 25 for field wiring diagram showing typical field 115-v
wiring. Check all factory and field electrical connections for
tightness.
Field-supplied wiring shall conform with the limitations of 63°F
(33°C) rise.
ELECTRICAL SHOCK AND FIRE HAZARD
Failure to follow this warning could result in serious injury,
death, or property damage.
The cabinet MUST have an uninterrupted or unbroken ground
according to NEC ANSI/NFPA 70-2002 and Canadian Elec-
trical Code CSA C22.1 or local codes to minimize personal
injury if an electrical fault should occur. This may consist of
electrical wire, conduit approved for electrical ground or a
listed, grounded power cord (where permitted by local code)
when installed in accordance with existing electrical codes.
Refer to the power cord manufacturer’s ratings for proper
wire gauge. Do not use gas piping as an electrical ground.
FURNACE MAY NOT OPERATE
Failure to follow this caution may result in furnace operation
stopping and water pipes freezing during cold weather.
Furnace control must be grounded for proper operation or
control will lock out. Control is grounded through
green/yellow wire routed to gas valve and manifold bracket
screw.
115-V Wiring
Verify that the voltage, frequency, and phase correspond to that
specified on unit rating plate. Also, check to be sure that service
provided by utility is sufficient to handle load imposed by this
equipment. Refer to rating plate or Table 7 for equipment electrical
specifications.
U.S. installations: Make all electrical connections in accordance
with National Electrical Code (NEC) ANSI/NFPA 70-2002 and
any local codes or ordinances that might apply.
Canadian installations: Make all electrical connections in accor-
dance with Canadian Electrical Code CSA C22.1 or authorities
having jurisdiction.
FIRE HAZARD
Failure to follow this warning could result in serious injury,
death, or property damage.
Do not connect aluminum wire between disconnect switch
and furnace. Use only copper wire.
Use a separate, fused branch electrical circuit with a properly sized
fuse or circuit breaker for this furnace. See Table 7 for wire size
and fuse specifications. A readily accessible means of electrical
disconnect must be located within sight of the furnace.
NOTE: Proper polarity must be maintained for 115-v wiring. If
polarity is incorrect, control LED status indicator light will flash
rapidly and furnace will NOT operate.
J-BOX RELOCATION
NOTE: If factory location of J-Box is acceptable, go to next
section (Electrical Connection to J-Box).
NOTE: On 14″wide casing models, the J-Box shall not be
relocated to other side of furnace casing when the vent pipe is
routed within the casing.
1. Remove and save two screws holding J-box. (See Fig. 22.)
NOTE: The J-Box cover need not be removed from the J-Box in
order to move the J-Box. Do NOT remove green ground screw
inside J-Box. The ground screw is not threaded into the casing
flange and can be lifted out of the clearance hole in casing while
swinging the front edge of the J-Box outboard of the casing.
Table 6—Maximum Capacity of Pipe*
NOMINAL
IRON
PIPE
SIZE
(IN.)
INTERNAL
DIAMETER
(IN.)
LENGTH OF PIPE (FT)
10 20 30 40 50
1/2 0.622 175 120 97 82 73
3/4 0.824 360 250 200 170 151
11.049 680 465 375 320 285
1-1/4 1.380 1400 950 770 660 580
1-1/2 1.610 2100 1460 1180 990 900
* Cubic ft of natural gas per hr for gas pressures of 0.5 psig (14–in. wc) or less
and a pressure drop of 0.5–in wc (based on a 0.60 specific gravity gas).
Ref: Table 12.2 ANSI Z223-2002/NFPA 54-2002.
→Fig. 21a—Right Side Gas Entry Example
A02327
Fig. 21b—Typical Gas Pipe Arrangement
A02035
UNION
SEDIMENT
TRAP
MANUAL
SHUTOFF
VALVE
(REQUIRED
GAS
SUPPLY
19
→
→
→
→