Bryant 926TB User Manual

926TB
TWO--STAGE, VARIABLE--SPEED ECM
MUL TIPOISE CONDENSING GAS FURNACE

Installation, Start--up, Operating and

Service and Maintenance Instructions

NOTE: Read the entire instruction manual before starting the installation.

SECTIONS

SAFETY CONSIDERATIONS 4.........................

INTRODUCTION 5...................................

CODES AND STANDARDS 6...........................

ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS 6...

ACCESSORIES 6.....................................

LOCATION 7........................................

AIR FOR COMBUSTION AND VENTILATION 9..........

CONDENSATE TRAP 12...............................

CONDENSATE DRAIN 13.............................

INSTALLATION 17...................................

AIR DUCTS 30.......................................

GAS PIPING 30......................................

ELECTRICAL CONNECTIONS 32.......................

VENTING 38........................................

START--UP, ADJUSTMENT, AND SAFETY CHECK 60......

SERVICE AND MAINTENANCE PROCEDURES 70........

SEQUENCE OF OPERATION 78........................

PARTS REPLACEMENT GUIDE 84......................

TABLES

Loose Parts Bag Contents 5..............................

Minimum Clearances to Combustible Materials 5.............

Minimum Free Area Required 11.........................

Minimum Space Volumes 11.............................

Filter Size Information 23...............................

Opening Dimensions 23................................

Air Delivery CFM 26...................................

Maximum Capacity of Pipe 31...........................

Electrical Data 35......................................

Combustion--Air Vent Pipe, Fitting & Cement Material.. 40.....

Vent Termination Kit for Direct Vent (2--Pipe) Systems 41......

Hangar Spacing 49.....................................

Maximum Allowable Exposed Vent Lengths Insulation 52......

Maximum Equivalent Vent Length 53......................

Deductions from Maximum Equivalent Vent Length 53........

Altitude Derate Multiplier for U.S.A. 68....................

Blower Off Delay Setup Switch 68........................

Gas Rate 68..........................................

Orifice Size and Manifold Pressure 69.....................

Use of the AHRI Certified TM Mark indicates a
manufacturer’s participati on in the program.
For verification of certification for indi vidual
products, go to www.ahridirectory.org .

Portions of the text and tables are reprinted from NFPA 54/ANSI Z223.1E, 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.

Required Notice for Massachusetts Installations

IMPORTANT

The Commonwealth of Massachusetts requires compliance with regulation 248 CMR as follows:

5.08: Modifications to NFPA--54, Chapter 10

2) Revise 10.8.3 by adding the following additional requirements:

a. For all side wall horizontally vented gas fueled equipment installed in every dwelling, building or structure used in

whole or in part for residential purposes, including those owned or operated by the Commonwealth and where the
side wall exhaust vent termination is less than seven (7) feet above finished grade in the area of the venting,
including but not limited to decks and porches, the following requirements shall be satisfied:

1. INSTALLATION OF CARBON MONOXIDE DETECTORS. At the time of installation of the side wall horizontal vented
gas fueled equipment, the installing plumber or gasfitter shall observe that a hard wired carbon monoxide detector with an
alarm and battery back--up is installed on the floor level where the gas equipment is to be installed. In addition, the installing
plumber or gasfitter shall observe that a battery operated or hard wired carbon monoxide detector with an alarm is installed on
each additional level of the dwelling, building or structure served by the side wall horizontal vented gas fueled equipment. It
shall be the responsibility of the property owner to secure the services of qualified licensed professionals for the installation of
hard wired carbon monoxide detectors

a. In the event that the side wall horizontally vented gas fueled equipment is installed in a crawl space or an attic, the hard wired

carbon monoxide detector with alarm and battery back--up may be installed on the next adjacent floor level.

b. In the event that the requirements of this subdivision can not be met at the time of completion of installation, the owner shall

have a period of thirty (30) days to comply with the above requirements; provided, however, that during said thirty (30) day
period, a battery operated carbon monoxide detector with an alarm shall be installed.

2. APPROVED CARBON MONOXIDE DETECTORS. Each carbon monoxide detector as required in accordance with the
above provisions shall comply with NFPA 720 and be ANSI/UL 2034 listed and IAS certified.

3. SIGNAGE. A metal or plastic identification plate shall be permanently mounted to the exterior of the building at a minimum
height of eight (8) feet above grade directly in line with the exhaust vent terminal for the horizontally vented gas fueled
heating appliance or equipment. The sign shall read, in print size no less than one--half (1/2) inch in size, ”GAS VENT
DIRECTLY BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS”.

4. INSPECTION. The state or local gas inspector of the side wall horizontally vented gas fueled equipment shall not approve the
installation unless, upon inspection, the inspector observes carbon monoxide detectors and signage installed in accordance
with the provisions of 248 CMR 5.08(2)(a)1 through 4.

5. EXEMPTIONS: The following equipment is exempt from 248 CMR 5.08(2)(a)1 through 4:

(1.) The equipment listed in Chapter 10 entitled ”Equipment Not Required To Be Vented” in the most current edition of

NFPA 54 as adopted by the Board; and

(2.) Product Approved side wall horizontally vented gas fueled equipment installed in a room or structure separate from

the dwelling, building or structure used in whole or in part for residential purposes.

c. MANUFACTURER REQUIREMENTS -- GAS EQUIPMENT VENTING SYSTEM PROVIDED. When the

manufacturer of Product Approved side wall horizontally vented gas equipment provides a venting system design
or venting system components with the equipment, the instructions provided by the manufacturer for installation of
the equipment and the venting system shall include:

1. Detailed instructions for the installation of the venting system design or the venting system components; and

2. A complete parts list for the venting system design or venting system.

d. MANUFACTURER REQUIREMENTS -- GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED. When

the manufacturer of a Product Approved side wall horizontally vented gas fueled equipment does not provide the
parts for venting the flue gases, but identifies “special venting systems”, the following requirements shall be
satisfied by the manufacturer:

1. The referenced “special venting system” instructions shall be included with the appliance or equipment installation
instructions; and

2. The “special venting systems” shall be Product Approved by the Board, and the instructions for that system shall include a
parts list and detailed installation instructions.

e. A copy of all installation instructions for all Product Approved side wall horizontally vented gas fueled equipment,

all venting instructions, all parts lists for venting instructions, and/or all venting design instructions shall remain
with the appliance or equipment at the completion of the installation.

For questions regarding these requirements, please contact the Commonwealth of Massachusetts Board of State Examiners of Plumbers and

Gas Fitters, 239 Causeway Street, Boston, MA 02114. 617--727-- 9952.

2

A B C D

FURNACE SIZE

CABINET WIDTH OUTLET WIDTH

BOTTOM INLET

WIDTH

AIR INTAKE

SHIP WT.

LB (KG)

30040V14 14 --- 3/16 (361) 12---1/2 (319) 12---9/16 (322) 7---1/8 (181) 123 (55.8)
36040V17 17---1/2 (445) 15---7/8 (403) 16 (406) 8---3/4 (222) 133 (60.3)
36060V14 14 --- 3/16 (361) 12---1/2 (319) 12---9/16 (322) 7---1/8 (181) 132 (59.9)
42060V17 17---1/2 (445) 15---7/8 (403) 16 (406) 8---3/4 (222) 139 (63.0)
48080V17 17---1/2 (445) 15---7/8 (403) 16 (406) 8---3/4 (222) 147 (66.7)
60080V21 21 (533) 19 --- 3/8 (492) 19---1/2 (495) 10---1/2 (267) 156 (70.7)
60100V21 21 (533) 19 --- 3/8 (492) 19---1/2 (495) 10---1/2 (267) 170 (77.1)
66120V24 24---1/2 (622) 22---7/8 (581) 23 (584) 12---1/4 (311) 190 (86.2)

Fig. 1 -- Dimensional Drawing

3

A180203

SAFETY CONSIDERATIONS

!

WARNING

FIRE, EXPLOSION, ELECTRICAL SHOCK, AND
CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in dangerous
operation, personal injury, death, or property damage.

Improper installation, adjustment, alteration, service,
maintenance, or use can cause carbon monoxide poisoning,
explosion, fire, electrical shock, or other conditions which
may cause personal injury or property damage. Consult a
qualified service agency, local gas supplier, or your
distributor or branch for information or assistance. The
qualified service agency must use only factory--authorized
and listed kits or accessories when modifying this product.

!

WARNING

FIRE, EXPLOSION, ELECTRICAL SHOCK, AND
CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in dangerous
operation, personal injury, death, or property damage.

Furnaces shall NOT be twinned (i.e. tandem or staged
operation) unless approved in factory technical
specifications literature for the furnace. A factory
authorized, field--supplied Twinning Kit MUST be used.
Consult furnace pre--sale literature for specific models
approved for twinning and the correct twinning kit.
Twinned furnaces must be installed on both a common
supply AND a common return duct system as shown in the
Twinning Kit Installation Instructions. Only two furnaces
can be twinned on a common supply and return duct system
using a factory authorized twinning kit.

!

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal injury,
death, or property damage.

Solvents, cements and primers are combustible. Keep away
from heat, sparks and open flame. Use only in well--ventilated
areas. Avoid breathing in vapor or allowing contact with skin
or eyes.

!

CAUTION

FURNACE RELIABILITY HAZARD

Failure to follow this caution may result in unit component
damage.

Application of this furnace should be indoors with special
attention given to vent sizing and material, gas input rate,
air temperature rise, unit leveling, and unit sizing.

Improper installation, adjustment, alteration, service, maintenance,
or use can cause explosion, fire, electrical shock, or other
conditions which may cause death, personal injury, or property
damage. Consult a qualified installer, service agency, or your
distributor or branch for information or assistance. The qualified
installer or agency must use factory-authorized kits or accessories
when modifying this product. Refer to the individual instructions
packaged with the kits or accessories when installing.

Installing and servicing heating equipment can be hazardous due to
gas and electrical components. Only trained and qualified

personnel should install, repair, or service heating equipment.

Untrained personnel can perform basic maintenance functions such
as cleaning and replacing air filters. All other operations must be
performed by trained service personnel. When working on heating
equipment, observe precautions in literature, on tags, and on labels
attached to or shipped with furnace and other safety precautions
that may apply.

These instructions cover minimum requirements and conform to
existing national standards and safety codes. In some instances,
these instructions exceed certain local codes and ordinances,
especially those that may not have kept up with changing
residential construction practices. We require these instructions as a
minimum for a safe installation.

Follow all safety codes. Wear safety glasses, protective clothing,
and work gloves. Have a fire extinguisher available. Read these
instructions thoroughly and follow all warnings or cautions
included in literature and attached to the unit.

!

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care
and wear appropriate protective clothing, safety glasses and
gloves when handling parts, and servicing furnaces.

This is the safety--alert symbol . When you see this symbol on
the furnace and in instructions or manuals, be alert to the potential
for personal injury.

Understand the signal words DANGER, WARNING,and

CAUTION. These words are used with the safety --alert symbol.
DANGER identifies the most serious hazards which will result in

severe personal injury or death. WARNING signifies a hazard
which could result in personal injury or death. CAUTION is used
to identify hazards which may result in minor personal injury or
product and property damage. NOTE and NOTICE are used to
highlight suggestions which will result in enhanced installation,
reliability, or operation.

1. Use only with type of gas approved for this furnace. Refer
to the furnace rating plate.

2. Install this furnace only in a location and position as spe­cified in the “Location” section of these instructions.

3. Provide adequate combustion and ventilation air to the fur­nace space as specified in “Air for Combustion and Ventila­tion” section.

4. Combustion products must be discharged outdoors. Con­nect this furnace to an approved vent system only, as spe­cified in the “Venting” section of these instructions.

5. Never test for gas leaks with an open flame. Use a commer­cially available soap solution made specifically for the de­tection of leaks to check all connections, as specified in the
“Gas Piping” section.

6. Always install furnace to operate within the furnace’s inten­ded temperature--rise range with a duct system which has an
external static pressure within the allowable range, as spe­cified in the “Start--Up, Adjustments, and Safety Check”
section. See furnace rating plate.

7. When a furnace is installed so that supply ducts carry air
circulated by the furnace to areas outside the space contain­ing the furnace, the return air shall also be handled by
duct(s) sealed to the furnace casing and terminating outside
the space containing the furnace. See “Air Ducts” section.

4

8. A gas--fired furnace for installation in a residential garage
must be installed as specified in the warning box in the
“Location” section.

9. The furnace may be used for construction heat provided that
the furnace installation and operation complies with the first
CAUTION in the LOCATION section of these instruc­tions.

10. These Multipoise Gas--Fired Furnaces are CSA design--cer­tified for use with natural and propane gases (see furnace
rating plate) and for installation in alcoves, attics, base­ments, closets, utility rooms, crawlspaces, and garages. The
furnace is factory --shipped for use with natural gas. A CSA
(A.G.A. and C.G.A.) listed accessory gas conversion kit is
required to convert furnace for use with propane gas.

11. See Ta b l e 1 for required clearances to combustible con­struction.

12. Maintain a 1-- in. (25 mm) clearance from combustible ma­terials to supply air ductwork for a distance of 36 in. (914
mm) horizontally from the furnace. See NFPA 90B or local
code for further requirements.

Table 1 – Minimum Clearances to Combustible Materials for

All Units

POSITION CLEARANCE

Front (Combustion air open-

ings in furnace and in struc-

All Sides of Supply Plenum *1 in. (25 mm)

*Consult local building codes.

Rear 0(0mm)

ture)

Required for service *24 in. (610 mm)

Sides 0(0mm)

Vent 0(0mm)

Top of Furnace 1in. (25mm)

1in.(25mm)

13. These furnaces SHALL NOT be installed directly on carpet­ing, combustible 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 a manufacturer’s
specified coil assembly or coil box (see furnace clearance
label).

NOTICE

Important Installation and Start--up Procedures

Failure to follow this procedure may result in a nuisance
smoke or odor complaint.

The manifold pressure, gas rate by meter clocking,
temperature rise and operation must be checked after
installation. Minor smoke and odor may be present
temporarily after start--up from the manufacturing process.
Some occupants are more sensitive to this minor smoke and
odor. It is recommended that doors and windows be open
during the first heat cycle.

INTRODUCTION

This 4-- way multipoise Category IV condensing furnace is CSA
design--certified as a direct--vent (2-pipe) or non-direct vent
(1-pipe) furnace. See Fig. 3. The furnace is factory--shipped for
use with natural gas. The furnace can be converted in the field for
use with propane gas when a factory-supplied conversion kit is
used. Refer to the furnace rating plate for conversion kit
information.

This furnace is not approved for installation in mobile homes,
recreational vehicles, or outdoors.

This furnace is designed for minimum continuous return--air
temperature of 60_F(15_C) db or intermittent operation down to
55_F(13_C) db such as when used with a night setback
thermostat. Return-air temperature must not exceed 80_F(27_C)
db. Failure to follow these return-air temperature limits may affect
reliability of heat exchangers, motors, and controls. See Fig. 2.

The furnace should be sized to provide 100 percent of the design
heating load requirement plus any margin that occurs because of
furnace model size capacity increments. None of the furnace
model sizes can be used if the heating load is 20,000 BTU or
lower. Use Air Conditioning Contractors of America (Manual J
and S); American Society of Heating, Refrigerating, and
Air-Conditioning Engineers; or other approved engineering
method to calculate heating load estimates and select the furnace.
Excessive oversizing of the furnace may cause the furnace and/or
vent to fail prematurely, customer discomfort and/or vent freezing.

Failure to follow these guidelines is considered faulty installation
and/or misapplication of the furnace; and resulting failure, damage,
or repairs may impact warranty coverage.

For accessory installation details, refer to the applicable instruction
literature.

NOTE: Remove all shipping materials, loose parts bag, and
literature before operating the furnace. See Ta b le 2.

SUPPLY AIR

SEE PRODUCT DATA FOR
ACCESSORY CONDENSATE
TRAP HEATER AND CONDENSATE
DRAIN LINE PROTECTION.

80 / 27˚C

60

/ 16˚C

A150573

Fig. 2 -- Freeze Protection and Return Air Temperature

Table 2 – Loose Parts Bag

DESCRIPTION QUANTITY

Outlet Restrictor Plate (provided with 40K BTUH

furnaces only; see Note)

AirIntakePipeFlange 1

Vent Pipe Flange 1

Pipe Flange Gaskets 2

Sharp Tip Screws (Vent and Inlet Flanges) 10

Vent Pipe Coupling 1

Vent Pipe Coupling Clamps 2

Pressure Switch Tube 1

Rubber Drain Elbow 1

Drain Tube Clamps 4

1 / 2 --- i n . C P V C t o 3 / 4 --- i n . P V C P i p e A d a p t e r 1

Gas Line Grommet 1

Junction Box Cover 1

Junction Box Base 1

Green Ground Screw 1

Blunt Tip Screws (Junction Box) 3

Thermostat Wire Grommet 1

Drain Extension Tube (Z --- pipe) (Provided separ-

ately in furnace)

1

1

NOTE: The 40K models are the only furnaces that receive the
outlet restrictor in loose parts bag. See Maximum Equivalent Vent
Length Table for usage.

5

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.

In the United States and Canada, follow all codes and standards for
the following:

Safety

S US: Current edition of National Fuel Gas Code (NFGC) NFPA

54/ANSI Z223.1 and the Installation Standards, Warm Air
Heating and Air Conditioning Systems ANSI/NFPA 90B

S CANADA: Current edition of National Standard of Canada,

Natural Gas and Propane Installation Code (NSCNGPIC)
CAN/CSA B149.1

General Installation

S US: NFGC and the NFPA 90B. For copies, contact the National

Fire Protection Association Inc., Batterymarch Park, Quincy,
MA 02269; or for only the NFGC contact the American Gas
Association, 400 N. Capitol, N.W., Washington DC 20001

S CANADA: NSCNGPIC. For a copy, contact Standard Sales,

CSA International, 178 Rexdale Boulevard, Etobicoke
(Toronto), Ontario, M9W 1R3, Canada

Combustion and Ventilation Air

S US: Section 9.3 of the current edition of NFPA54/ANSI Z223.1

Air for Combustion and Ventilation

S CANADA: Part 8 of the current edition of CAN/CSA B149.1,

Venting Systems and Air Supply for Appliances

Duct Systems

S US and CANADA: Air Conditioning Contract ors Associ ation

(ACCA) Manual D, Sheet Metal and Air Conditioning Contract ors
National Association (SMACNA), or American Society of Heating,
Refri geration, and Air Conditioning Engineer s (ASHRAE)
Fundament als Handbook

Acoustical Lining and Fibrous Glass Duct

S US and CANADA: Current edition of SMACNA, NFPA 90B as

tested by UL Standard 181 for Class I Rigid Air Ducts

Gas Piping and Gas Pipe Pressure Testing

S US: Current edition of NFPA 54/ANSI Z223.1 NFGC; Chapters

5, 6, 7, and 8 and nationa l plumbing codes.
CANADA: Current edition of CAN/CSA--B149.1, Parts 4, 5, 6,
and 9.

In the state of Massachusetts:

S This product must be installed by a lice nsed plumber or gas fitter.
S When flexible connectors are used, the maximum length shall

not exceed 36 in. (914 mm).

S When lever type gas shutoffs are used they shall be T--handle type.
S The use of copper tubing for gas piping is not approved by the

state of Massachusetts.

Electrical Connections

S US: Current edition of National Electrical Code (NEC) NFPA

70.

S CANADA: Current edition of Canad ian Electrical Code CS A

C22.1

Condensate Drain Connection

S US: Current edition of National Standard Plumb ing Code,

Section 8.7.

S Canada: Current edition of Natio nal Plumbing Code of Canada.

ELECTROSTATIC DISCHARGE (ESD)

PRECAUTIONS PROCEDURE

!

CAUTION

FURNACE RELIABILITY HAZARD

Failure to follow this caution may result in unit component
damage.

Electrostatic discharge can affect electronic components.
Take precautions during furnace installation and servicing
to protect the furnace electronic control. Precautions will
prevent electrostatic discharges from personnel and hand
tools which are held during the procedure. These
precautions will help to avoid exposing the control to
electrostatic discharge by putting the furnace, the control,
and the person at the same electrostatic potential.

1. Disconnect all power to the furnace. Multiple disconnects
may be required. DO NOT TOUCH THE CONTROL

OR ANY WIRE CONNECTED TO THE CONTROL
PRIOR TO DISCHARGING YOUR BODY’S
ELECTROSTATIC CHARGE TO GROUND.

2. Firmly touch the clean, unpainted, metal surface of the fur­nace chassis which is close to the control. Tools held in a
person’s hand during grounding will be satisfactorily dis­charged.

3. After touching the chassis, you may proceed to service the
control or connecting wires as long as you do nothing to
recharge your body with static electricity (for example; DO
NOT move or shuffle your feet, do not touch ungrounded
objects, etc.).

4. If you touch ungrounded objects (and recharge your body
with static electricity), firmly touch a clean, unpainted metal
surface of the furnace again before touching control or
wires.

5. Use this procedure for installed and uninstalled (ungroun­ded) furnaces.

6. Before removing a new control from its container, discharge
your body’s electrostatic charge to ground to protect the
control from damage. If the control is to be installed in a
furnace, follow items 1 through 4 before bringing the con­trol or yourself in contact with the furnace. Put all used and
new controls into containers before touching ungrounded
objects.

7. An ESD service kit (available from commercial sources)
mayalsobeusedtopreventESDdamage.

ACCESSORIES

See Product Data Sheet for a list of accessories for this product.

6

LOCATION

!

CAUTION

PERSONAL INJURY AND/OR PROPERTY
DAMAGE HAZARD

Improper use or installation of this furnace may result in
premature furnace component failure. Unless otherwise
prohibited, 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
maintained between 55_F(13_C) and 80_F(27_C), with
no evening setback or shutdown. The use of the furnace
while the structure is under construction is deemed to be
intermittent operation per our installation instructions.

--The air temperature rise is within the rated rise range on
the furnace rating plate, and the gas input rate has been set
to the nameplate value.

--The filters used to clean the circulating air during the
construction process must be either changed or thoroughly
cleaned prior to occupancy.

--The furnace, ductwork and filters are cleaned as necessary
to remove drywall dust and construction debris from all
HVAC system components after construction is completed.

--Verify proper furnace operating conditions including
ignition, gas input rate, air temperature rise, and venting
according to these installation instructions.

General

These furnaces are shipped with materials to assist in proper
furnace installation. These materials are shipped in the main
blower compartment. See Ta b l e 2 for loose parts bag contents.
This furnace must:

S be installed so the electrical components are protected from

water.

S not be installed directly on any combustible material other than

wood flooring (refer to SAFETY CONSIDERATIONS).

S be located close to the chimney or vent and attached to an air

distribution system. Refer to Air Ducts section.

S be provided ample space for servicing and cleaning. Always

comply with minimum fire protection clearances shown in
Table 1 or on the furnace clearance to combustible construction
label.

!

WARNING

CARBON MONOXIDE POISONING / COMPONENT
DAMAGE 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
OUTDOOR AIR for combustion due to chemical exposures:

S Commercial buildings
S Buildings with indoor pools
S Laundry rooms
S Hobby or craft rooms
S Chemical storage areas

If air is exposed to the following substances, it should not be used
for combustion air, and outdoor air may be required for
combustion:

S Permanent wave solutions
S Chlorinated waxes and cleaners
S Chlorine based swimming pool chemicals
S Water softening chemicals
S De--icing salts or chemicals
S Carbon tetrachloride
S Halogen type refrigerants
S Cleaning solvents (such as perchloroethylene)
S Printing inks, paint removers, varnishes, etc.
S Hydrochloric acid
S Cements and glues
S Antistatic fabric softeners for clothes dryers
S Masonry acid washing materials

All fuel-- burning equipment must be supplied with air for fuel
combustion. Sufficient air must be provided to avoid negative
pressure in the equipment room or space. A positive seal must be
made between the furnace cabinet and the return --air duct to
prevent pulling air from the burner area.

7

THE BLOWER IS LOCATED

TO THE RIGHT OF THE

BURNER SECTION, AND

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

Fig. 3 -- Multipoise Orientations

!

WARNING

FIRE, INJURY OR DEATH HAZARD

Failure to follow this warning could result in personal
injury, death and/or property damage.

When the furnace is installed in a residential garage, the
burners and burner ignition devices must be located at least
18 in. (457 mm) above the floor. The furnace must be
located or protected to avoid damage by vehicles. When the
furnace is installed in a public garage, airplane hangar, or
other building having a hazardous atmosphere, the furnace
must be installed in accordance with the current edition of
NFPA 54/ANSI Z223.1 or CAN/CSA B149.2. See Fig. 4.

THE BLOWER IS

LOCATED TO THE LEFT

OF THE BURNER SECTION,

AND CONDITIONED AIR IS

DISCHARGED TO THE RIGHT.

!

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal
injury, death and/or property damage.

Do not install the furnace on its back or hang furnace with
control compartment facing downward. Safety control
operation will be adversely affected. Never connect
return--air ducts to the back of the furnace. See Fig. 5.

A12181

18-IN. (457.2 mm)

MINIMUM TO BURNERS

Fig. 4 -- Installation in a Garage

A93044

BACK POSITIONED

DOWNWARD

AIR RETURN

BACK POSITIONED

UPWARD

CUT IN BACK

A12182

Fig. 5 -- Prohibited Installations

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.

8

AIR FOR COMBUSTION AND

VENTILATION

Introduction

Direct Vent (2--pipe) Applications

When the furnace is installed as a direct vent (2-pipe) furnace, no
special provisions for air for combustion are required. However,
other gas appliances installed in the space with the furnace may
require outside air for combustion. Follow the guidelines below to
insure that other gas appliances have sufficient air for combustion.

Non--Direct Vent (1--pipe) Applications

When the furnace is installed as a non-direct vent (1-pipe) furnace,
it will be necessary to insure there is adequate air for combustion.
Other gas appliances installed with the furnace may also require air
for combustion and ventilation in addition to the amount of
combustion air and ventilation air required for the furnace. Follow
the guidelines below to insure that the furnace and other gas
appliances have sufficient air for combustion.

Ventilated Combustion Air Applications

When the furnace is installed using the ventilated combustion air
option, the attic or crawlspace must freely communicate with the
outdoor to provide sufficient air for combustion. The combustion
air pipe cannot be terminated in attics or crawlspaces that use
ventilation fans designed to operate during the heating season. If
ventilation fans are present in these areas, the combustion air pipe
must terminate outdoors as a Direct Vent/ 2-Pipe system.

All air for combustion is piped directly to the furnace from a space
that is well ventilated with outdoor air (such as an attic, crawl space
or equipment closet) and the space is well isolated from the living
space or garage. In addition, other gas appliances installed in the
space with the furnace may require outside air for combustion.
Follow the guidelines below to insure that the roof or crawlspace
walls have sufficient free area to provide sufficient air for
combustion and ventilation for the furnaces. The guidelines below
can be used to insure that other gas appliances have sufficient air
for combustion.

Provisions for adequate combustion, ventilation, and dilution air
must be provided in accordance with:

S USA Installations: Section 9.3 of the current edition of NFPA

54/ANSI Z223.1, Air for Combustion and Ventilation and

applicable provisions of the local building codes.

S Canada: Part 8 of the current edition of CAN/CSA--B149.1,

Venting Systems and Air Supply for Appliances.

!

CAUTION

FURNACE CORROSION HAZARD

Failure to follow this caution may result in furnace damage.

Air for combustion must not be contaminated by halogen
compounds, which include fluoride, chloride, bromide, and
iodide. These elements can corrode heat exchangers and
shorten furnace life. Air contaminants are found in aerosol
sprays, detergents, bleaches, cleaning solvents, salts, air
fresheners, and other household products.

!

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal
injury or death.

The operation of exhaust fans, kitchen ventilation fans,
clothes dryers, attic exhaust fans or fireplaces could create a
NEGATIVE PRESSURE CONDITION at the furnace.
Make--up air MUST be provided for the ventilation devices,
in addition to that required by the furnace. Refer to the
Carbon Monoxide Poisoning Hazard warning in the venting
section of these instructions to determine if an adequate
amount of make--up air is available.

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.

S Spaces having less than 50 cubic feet per 1,000 Btuh (4.8 cubic

meters per kW) require the Outdoor Combustion Air Method.

S Spaces having at least 50 cubic feet per 1,000 Btuh (4.8 cubic

meters per kW) may use the Indoor Combustion Air,

Standard or Known Air Infiltration Method.

Outdoor Combustion Air Method

1. Provide the space with sufficient air for proper combustion,
ventilation, and dilution of flue gases using permanent hori­zontal or vertical duct(s) or opening(s) directly communicat­ing with the outdoors or spaces that freely communicate
with the outdoors.

2. Fig. 6 illustrates how to provide TWO OUTDOOR
OPENINGS, one inlet and one outlet combustion and vent­ilation air opening, to the outdoors.

a. One opening MUST commence within 12 in. (300 mm)

of the ceiling and the second opening MUST commence
within 12 in. (300 mm) of the floor.

b. Size openings and ducts per Fig. 6andTab le 3.

c. TWO HORIZONTAL DUCTS require 1 sq. in. (645 sq.

mm) of free area per 2,000 Btuh (1,100 mm
bined input for all gas appliances in the space per Fig. 6
and Ta b le 3.

d. TWO OPENINGS OR VERTICAL DUCTS require 1

sq. in. (645 sq. mm) of free area per 4,000 Btuh (550

2

/kW) for combined input of all gas appliances in the

mm
space per Fig. 6andTab l e 3.

3. ONE OUTDOOR OPENING requires:

a. 1 sq. in. (645 sq. mm) of free area per 3,000 Btuh (734

2

/kW) for combined input of all gas appliances in the

mm
space per Fig. 6andTab l e 3.

b. Not less than the sum of the areas of all vent connectors in

the space.

The opening shall commence within 12 in. (300 mm) of the
ceiling. Appliances in the space shall have clearances of at least 1
in. (25 mm) from the sides and back and 6 in. (150 mm) from the
front. The opening shall directly communicate with the outdoors or
shall communicate through a vertical or horizontal duct to the
outdoors or spaces (crawl or attic) that freely communicate with the
outdoors.

2

/kW) of com-

9

Indoor Combustion AirE 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.

!

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal
injury or death.

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.

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 4 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 4 -- Minimum Space V olumes were determined by using the
following equations from the current edition of the National Fuel

Gas Code ANSI Z223.1/NFPA 54, 9.3.2.2:

1. For other than fan--assisted appliances, such as a draft
hood--equipped water heater:

3

I

other

1000 Btu/hr

A04002

Volume

2. For fan--assisted appliances such as this furnace:

Other

=

21ft
ACH

of thefloor. The minimumdimensionof air openings shall
be at least 3 in. (80 mm). See Fig. 7.

c. Combining space on different floor levels.The volumesof

spaces on different floor levels shall be considered as com­municating spaces if connected by one or more permanent
openings in doors or floors having free area of at least 2

2

/1,000 Btuh (4,400 mm2/kW) of total input rating of

in.
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.
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.

4. Unusually tight construction is defined as Construction
with:

a. Walls and ceilings exposed to the outdoorshave 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.

2

/4,000 Btuh of total input

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 Ra-

tio in a. above.

c. Minimum size of Outdoor openings shall be the size re-

quiredin Outdoor Combustion Air Method abovemulti-
plied by reduction Factor in b. above. The minimum di­mension ofairopenings shallbe not lessthan 3 in.(80 mm).

3

Volume

If: Iother = combined input of all other than fan--assisted appliances
in Btuh/hr

Ifan = combined input of all fan--assisted appliances in Btuh/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 closeable doors between rooms.

b. Combining spaces on same floor level. Each opening shall

have freearea of at least 1 in.
of the total input rating of all gas appliances in the space,
but not less than 100 in.
commence within 12 in. (300 mm) of the ceiling and the
second opening shall commence within 12 in. (300 mm)

Fan

=

15ft
ACH

I

fan

1000 Btu/hr

2

/1,000Btuh (2,000 mm2/kW)

2

(0.06 m2). One opening shall

A04003

10

Table 3 – Minimum Free Area Required for Each Combustion Air Opening or Duct to Outdoors

TWO HORIZONTAL DUCTS

FURNACE

(1 SQ. IN./2,000 BTUH)

INPUT

(BTUH)

40,000*

60,000

80,000
100,000
120,000

140,000*

*Not all families have these models.

Free Area of

Opening and Duct

Sq. In (Sq. mm)

20 (12904) 5 (127) 14 (8696) 5 (127) 10 (6452) 4 (102)

30 (19355) 6 (152) 20 (13043) 5 (127) 15 (9678) 5 (127)

40 (25807) 7 (178) 27 (17391) 6 (152) 20 (12904) 5 (127)

50 (32258) 8 (203) 34 (21739) 7 (178) 25 (16130) 6 (152)

60 (38709) 9 (229) 40 (26087) 7 (178) 30 (19355) 6 (152)

70 (45161) 10 (254) 47 (30435) 8 (203) 35 (22581) 7 (178)

(1,100 SQ. MM/KW)

Round Duct

In. (mm) Dia

SINGLE DUCT OR OPENING

(1 SQ. IN./3,000 BTUH)

(734 SQ. MM/KW)

Free Area of

Opening and Duct

Sq. In (Sq. mm)

Round Duct

In. (mm) Dia

Free Area of Open-

TWO OPENINGS OR

VERTICAL DUCTS

(1 SQ. IN./4,000 BTUH)

(550 SQ. MM/KW)

ing an d Duct

Sq. In (mm)

EXAMPLES: Determining Free Area

FURNACE WATER HEATER TOTAL INPUT

100,000 + 30,000 = (130,000 divided by 4,000) = 32.5 Sq. In. for each two Vertical Ducts or Openings

60,000 + 40,000 = (100,000 divided by 3,000) = 33.3 Sq. In. for ea ch Single Duct or Opening

80,000 + 30,000 = (110,000 divided by 2,000) = 55.0 Sq. In. for each two Horizontal Ducts

Table 4 – Minimum Space Volumes for 100% Combustion, Ventilation and Dilution Air from Outdoors

OTHER THAN FAN-ASSISTED TOTAL

(1,000’S BTUH GAS INPUT RATE)

ACH

0.60

0.50

0.40

0.30

0.20

0.10

0.00

NP = Not Permitted

30 40 50 40 60 80 100 120 140

1,050

(29.7)

1,260
(35.6)

1,575
(44.5)

2,100
(59.4)

3,150
(89.1)

6,300

(178.0)

NP NP NP NP NP NP NP NP NP

1,400
(39.6)

1,680
(47.5)

2,100
(59.4)

2,800
(79.2)

4,200

(118.9)

8,400

(237.8)

1,750
(49.5)

2,100
(59.4)

2,625
(74.3)

3,500
(99.1)

5,250

(148.6)

10,500

(297.3)

SpaceVolumeFt3(M3)

1,400
(39.6)

1,680
(47.5)

2,100
(59.4)

2,800
(79.2)

4,200

(118.9)

8,400

(237.8)

1,500
(42.5)

1,800
(51.0)

2,250
(63.7)

3,000
(84.9)

4,500

(127.3)

9,000

(254.6)

FAN-ASSISTED TOTAL

(1,000’S BTUH GAS INPUT RATE)

2,000

(56.6)

2,400

(67.9)

3,000

(84.9)

4,000

(113.2)

6,000

(169.8)

12,000

(339.5)

2,500
(70.8)

3,000
(84.9)

3,750

(106.1)

5,000

(141.5)

7,500

(212.2)

15,000
(424.4)

3,000
(84.9)

3,600

(101.9)

4,500

(127.3)

6,000

(169.8)

9,000

(254.6)

18,000
(509.2)

Round Duct

In. (mm) Dia.

3,500

(99.1)

4,200

(118.9)

5,250

(148.6)

7,000

(198.1)

10,500
(297.1)

21,000
(594.1)

*Minimum dimensions of 3‐in. (76mm)

NOTE: Use any of the following combinations of openings:

A & B, C & D, D & E, F & G

L12F012

Fig. 6 -- Air for Combustion, Ventilation, and Dilution for

Outdoors

* Minimum opening size is 100 sq in. (64516 sq. mm) with

minimum dimensions of 3‐in. (76mm)

{ Minimum of 3‐in. (76mm) when type‐B1 vent is used.

Fig. 7 -- Air for Combustion, Ventilation, and Dilution from

Indoors

11

L12F013

CONDENSATE TRAP

Condensate Trap -- Upflow Orientation

When the furnace is installed in the upflow position, it is not
necessary to relocate the condensate trap or associated tubing.
Refer to Fig. 9 for upflow condensate trap information. Refer to
Condensate Drain section for information how to install the
condensate drain.

Condensate Trap -- Downflow Orientation.

When the furnace is installed in the downflow position, the
condensate trap will be initially located at the upper left corner of
the collector box, as received from the factory. See the top image
in Fig. 10. When the furnace is installed in the downflow
orientation, the condensate trap must be relocated for proper
condensate drainage. See the bottom image in Fig. 10.

To Relocate the Condensate Trap:

S Orient the furnace in the downflow position.
S Fig. 10 shows the condensate trap and tubing before and after

relocation. Refe r to Fig. 10 to begin the trap conversi on.

S Refer to Condensate Drain section for information how to install the

condensate drain.

Condensate Trap -- Horizontal Orientation.

When the furna ce is installe d in the horizontal right position, the
condensate trap will be initially located at the bottom of the collector
box, as received from the factory. See the top image in Fig. 11.
When the furnace is installed in the horizontal left position, the
condensate trap will be initially located at the top of the collector box,
as received from the factory. See the top image in Fig. 12. In both
cases the trap must be repositioned on the collector box for proper
condensate drainage. See the bottom image s in Fig. 11 and 12.

A field-- supplied, accessory Horizontal Installation Kit (trap
grommet ) is require d for all direct--vent horizontal insta l lations (only).
The kit contains a rubber casing grommet designed to sea l between
the furnace casing and the condensa t e trap. See Fig. 8.

NOTE: Trap grommet is required only for direct-vent
applications.

NOTICE

The field--supplied, accessory horizontal drain trap grommet is
ONLY REQUIRED FOR DIRECT VENT APPLICATIONS.
It it NOT required for applications using single-- pipe or
ventilated combustion air venting.

NOTICE

The condensate trap extends below the side of the casing in
the horizontal position. A minimum of 2--in. (51 mm) of
clearance is required between the casing side and the furnace
platform for the trap to extend out of the casing in the
horizontal position. Allow at least 1/4--in. per foot (20 mm
per meter) of slope down.

To Relocate the Condensate Trap:

S Remove the knockout in the casing for the condensate trap.
S Instal l the grommet in the casing when requir ed for direct--vent

horizontal applications.

S Orient the furnace in the desired position.
S Allow for 2 in. (51 mm) of clea rance underneath the furnace for the

condensate trap and drain line.

S Fig. 11 shows the condensate trap and tubing before and after

relocation in the horizontal right positi on.

S Fig. 12 shows the condensate trap and tubing before and after

relocation in the horizontal left posit ion.

S Refer to the appropriate figure to begin the trap conversion.
S Refer to Condensate Drain section for information how to install the

condensate drain.

Vent Pipe Clamp

Vent Elbow Clamp

Vent Elbow

Collector Box

Plug

Condensate Trap

Relief Port

Collector Box

Plugs

Condensate Trap

Relief Port

Remove knockout.
Install grommet before
relocating condensate
trap.

Fig. 8 -- Horizontal Drain Trap Grommet

A11582

12

Pressure Switch

UPFLOW TRAP CONFIGURATION

1 & 2 Stage Units

Port

Fig. 9 -- Upflow Trap Configuration

(Appearance may vary)

Condensate Trap

Outlet

A11307

Fig. 10 -- Downflow Trap Configuration

(Appearance may vary)

A11587

A11574

Fig. 12 -- Horizontal Left Configuration

(Appearance may vary)

CONDENSATE DRAIN CONNECTION

!

CAUTION

FROZEN AND BURST WATER PIPE HAZARD

Failure to protect against the risk of freezing may result in
property damage.

Special precautions MUST be made if installing furnace in an
area which may drop below freezing. This can cause improper
operation or damage to equipment. If furnace environment
has the potential of freezing, the drain trap and drain line must
be protected. The use of accessory drain trap heaters, electric
heat tape and/or RV antifreeze is required for these
installations.

Fig. 11 -- Horizontal Right Trap Configuration

(Appearance may vary)

A11573

!

CAUTION

PROPERTY DAMAGE HAZARD

Failure to follow this caution may result in burst water pipes
and/or property damage.

If a condensate pump is installed, a plugged condensate drain
or a failed pump may cause the furnace to shut down. Do not
leave the home unattended during freezing weather without
turning off water supply and draining water pipes or otherwise
protecting against the risk of frozen pipes.

13

DO NOT trap the drain line in any other location than at the
condensate drain trap supplied with the furnace. If possible, DO
NOT route the drain line where it may freeze. The drain line must
terminate at an inside drain to prevent freezing of the condensate
and possible property damage.
Special precautions MUST be made if installing furnace in an area
which may drop below 32_ F(0_ C). This can cause improper
operation or damage to the equipment. If the furnace environment
has the potential of freezing, the drain trap and drain line must be
protected. In areas where the temperature may be below 32_ F(0_
C), a Condensate Freeze Protection kit is required. The kit
includes a condensate trap with heat pad and replaces the
factory-- installed condensate trap. Refer to the Accessory section
of the Product Datafor current kit number. A self-- regulating,
shielded and waterproof heat tape rated at 3 to 6 watt per foot (10
to 20 watt per meter) at 115 volt, 40_F(4_C)maybeusedto
provide freeze protection of the remaining condensate drain line.
Wrap the drain trap and drain line with the heat tape and secure
with appropriate plastic ties. Follow the heat tape manufacturer’s
recommendations. Prime the trap before furnace operation.
The condensate drain line must be supported and/or secured per
local codes. Supports and clamps should be spaced to prevent the
drain line from sagging or being dislocated from the furnace or
termination point. In the absence of local codes, consult the current
edition of the National Standard Plumbing Code, in the U.S. or the
current edition of the National Plumbing Code of Canada.

Upflow/Downflow Orientation

In the Upflow or Downflow orientation, the condensate trap is
inside the furnace casing. The condensate drain must be routed
from the trap through the furnace casing. The condensate drain can
be routed through the left or right side of the casing. (The left or
right side is as you are viewing/facing the furnace from the front.)
An indoor coil condensate drain or humidifier drain can be
connected to the external furnace condensate drain provided:

a. The drains are not hard piped together, and

b. There is an air gap at the point where the two drain lines

meet or

c. All condensate piping is at least 3/4-in. PVC and there is

a relief tee at the top of condensate drain piping as shown

in Fig. 18.
NOTE: On narrower casings, it may be easier to remove the
condensate trap, connect the drain line components and re-install
the condensate trap. Read the steps thoroughly to familiarize
yourself with the required steps.

For Right Side Condensate Drain:

1. Remove the 7/8--in. knock-- out from the right side of the
casing. See Fig. 13 for suggested knockout removal tech­nique.

2. Remove the pre--formed rubber drain elbow and two spring
clamps from the loose parts bag.

3. Slide a spring clamp 1--inch (25 mm) down the plain end
(the end without the formed grommet) of the drain elbow.

4. From inside the casing, insert the formed grommet end of
the elbow through the 7/8--in. knockout in the casing.

5. Pull the grommet through the casing from the outside until
it is seated in the knockout

6. Attach the plain end of the drain elbow to the outlet stub on
the drain trap. Secure the drain elbow to the trap with the
spring clamp.

The remaining drain line can be constructed from field supplied
1/2--in. CPVC or 3/4--in. PVC pipe, in compliance with local
building codes. A factory --supplied 1/2-- in. CPVC to 3/4--in. PVC
adapter is supplied in the loose parts bag for use as required.

7. Install the adapter or connect the 1/2-- in. CPVC pipe by
sliding a spring clamp over the open end of the grommet on
the outside the furnace casing.

8. Open the spring clamp and insert the long end of the
adapter or the 1/2--in. CPVC pipe into the outlet stub on the
drain tube.

9. Connect additional condensate piping to a code--approved
drain, or to a condensate pump approved for use with acidic
furnace condensate and compatible with mineral and
vegetable oils, such as canola oil.

Allow at least 1/4-in. per foot (20 mm per meter) of slope down
and away from the furnace in horizontal sections of drain line.
TIP FROM CONTRACTORS: Contractors have found that
temporarily removing the inducer assembly in upflow applications
while performing the steps, below, makes upflow left-- side drain
connections easier.

!

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care
and wear appropriate protective clothing, safety glasses and
gloves when handling parts, and servicing furnaces.

L12F019B

Fig. 13 -- Knockout Removal

For Left Side Condensate Drain Connection:

1. For left side condensate drainage, the drain line is routed
from the condensate trap, behind the inducer (upflow) or
gas valve (downflow) and out through the left side of the
furnace casing. A pre-formed 1/2--in. CPVC “Z-pipe” is
provided with the furnace. The Z-pipe is long enough to
extend across the casing for drain connections.

2. Locate the Z-pipe. Remove the pre-formed drain elbow and
four spring clamps from the loose parts bag.

3. The Z-pipe is connected to the condensate trap and the
outside of the furnace by modifying the formed rubber
drain elbow as shown in Fig. 14.

4. Remove the formed grommet from the rubber drain elbow
by cutting the elbow along the vertical line located about
1-- 3/8 in. (35 mm) away from the formed grommet. See Fig.

14. DO NOT DISCARD THE FORMED GROMMET
OR THE RUBBER ELBOW. Both of these pieces will be
used.

Assemble and route the drain line to the opposite side of the
furnace as detailed below:

5. Remove the knock-out from the left side of the casing. See
Fig. 13 for suggested knockout removal technique.)

6. From the outside of the casing, insert the angled end of the
Z-pipe through drain hole in the left side of the casing and
behind the inducer or gas valve. Allow the Z-pipe to
temporarily rest on the blower shelf (upflow) or burner box
(downflow). (NOTE: When the inducer housing has been
removed to ease installation in upflow applications, this step
is not needed.)

14

7. After inserting the Z pipe through the casing, slide a spring
clamp over each end of the Z pipe.

8. From inside the casing, insert the short end of the formed
grommet cut from the rubber drain elbow through the
7/8-in. drain knockout in the casing.

9. Pull the grommet through the casing from the outside until
it is seated in the knockout.

10. Align the Z-pipe with the long end of the grommet inside
the furnace and insert slightly. The angled end of the tube at
the other side of the casing should be facing the front of the
furnace.

11. Slide a spring clamp over the end of the remaining rubber
drain elbow.

12. Attach the drain elbow to the angled end of Z-pipe and the
drain trap outlet stub. Adjust the length of Z-pipe inserted
into the grommet at the opposite side of the furnace as
necessary for proper fit and positioning. In both upflow and
downflow orientations, the Z-pipe should NOT be resting
on any sheet metal parts.

13. Secure the rubber elbow to the drain trap and the Z-pipe
with spring clamps.

14. Secure the grommet to the Z-pipe with the spring clamp.

The remaining drain line can be constructed from field supplied
1/2--in. CPVC or 3/4--in. PVC pipe, in compliance with local
building codes. A factory-supplied 1/2--in. CPVC to 3/4--in. PVC
adapter is supplied in the loose parts bag for use as required.

15. Install the adapter or connect the 1/2--in. CPVC pipe by
sliding a spring clamp over the open end of the grommet on
the outside the furnace casing.

16. Open the spring clamp and insert the long end of the
adapter or the 1/2--in. CPVC pipe into the outlet stub on the
drain tube.

17. Connect additional condensate piping to a code-approved
drain, or to a condensate pump approved for use with acidic
furnace condensate and compatible with mineral and
vegetable oils, such as canola oil.

Allow at least 1/4-in. per foot (20 mm per meter) of slope down
and away from the furnace in horizontal sections of drain line.

NOTICE

The field--supplied, accessory horizontal drain trap grommet is
ONLY REQUIRED FOR DIRECT VENT APPLICATIONS.
It is NOT required for applications using single-- pipe or
ventilated combustion air venting.

INSTALL CLAMPS ON DRAIN TUBE
ATTACH DRAIN TUBE TO CONDENSATE
DRAIN TRAP

PULL DRAIN STUB
THROUGH CASING

OPEN SPRING CLAMP

INSERT FACTORYïSUPPLIED 1/2ïIN. CPVC
TO 3/4ïIN. PVC ADAPTER OR 1/2ïIN. CPVC PIPE

*CLAMP MAY BE LOCATED ON OUTSIDE OF DRAIN
TUBE

Fig. 15 -- Formed Rubber Drain Grommet

FORMED END
OF GROMMET

CONNECT SHORT END OF
’Z’ PIPE TO MODIFIED
DRAIN ELBOW

FACTORY SUPPLIED
1/2ïIN. CPVC TO 3/4ïIN.
PVC ADAPTER

DRAIN ELBOW “Z” DISCHARGE PIPE FOR LEFT SIDE

DRAIN IS ROUTED BEHIND INDUCER

FORMED END OF GROMMET. OPEN
SPRING CLAMP, INSERT 1/2ïIN. TO 3/4ïIN.
CPVC TO PVC ADAPTER OR CPVC PIPE

CUT FORMED END OFF
CONDENSATE DRAIN
ELBOW

TOP VIEW

ATTACH ELBOW TO
CONDENSATE TRAP

A11342A

TIP FROM CONTRACTORS: When installing the furnace
horizontally, use the entire drain elbow (that is, do NOT cut as
shown in Fig. 14 to connect the trap to the drain line. This helps to
prevent bumps and shocks to the drain line from damaging the
furnace drain trap. Avoid misalignment of the drain pipe which
may cause kinks in the elbow.

A11581

Fig. 14 -- Modify Rubber Drain Elbow

MODIFIED DRAIN ELBOW CON­NECT TO CONDENSATE TRAP
AND ’Z’ PIPE

LEFT SIDE DRAIN PIPE ORIENTATION FOR CONDENSATE DISCHARGE

NOTE: Remove Inducer Housing for easier access, if desired.

FRONT VIEW

Fig. 16 -- Drain Trap Connection and Routing

(Appearance may vary)

Horizontal Orientation

1. The condensate trap outlet extends 2--in. (51 mm) below the
furnace casing. Leave enough clearance between the furnace
and the furnace platform for the trap.

2. To allow for servicing the trap, the condensate drain elbow
in the loose parts bag can be used to make a coupler to
allow for future service of the condensate trap and drain
line.

3. Remove the knock-out for the condensate trap in the side of
the casing.

15

A170128

4. Install the drain trap grommet in the casing if required for
direct-- vent applications. If necessary, remove the trap,
install the grommet and re-install the trap.

5. Remove the pre-formed rubber drain elbow, and two spring
clamps from the loose parts bag.

6. Connect the full or modified elbow and/or grommet to the
outlet of the condensate trap with one spring clamp. Avoid
misalignment of the drain pipe which may cause kinks in
the elbow or grommet.

7. The remaining drain line can be constructed from field-­supplied 1/2--in. CPVC or 3/4--in. PVC pipe, in compliance
with local building codes. A factory--supplied 1/2--in.
CPVC to 3/4--in. PVC adapter is supplied in the loose parts
bag for use as required.

Evaporator Coil

8. Install the adapter or connect the 1/2-- in. CPVC pipe by
sliding a spring clamp over the open end of the elbow or
grommet on the outside the furnace casing.

9. Open the spring clamp and insert the long end of the
adapter or the 1/2--in. CPVC pipe into the outlet stub on the
drain tube.

10. Connect additional condensate piping to a code--approved
drain, or to a condensate pump approved for use with acidic
furnace condensate and compatible with mineral and
vegetable oils, such as canola oil.

Allow at least 1/4-in. per foot (20 mm per meter) of slope down
and away from the furnace in horizontal sections of drain line.

AIRFLOW

OF

DIRECTION

+

AIRFLOW

OF

DIRECTION

+

+

+

Condensing

+

Furnace

+

+

< +

< +

-

Blower

+ = Positive pressure
< + = Pressure lower than areas with +

+

+

− = Negative pressure

+

Blower creates positive pressure.

Positive pressure extends into coil

+

condensate drain (no trap).

< +

Furnace condensate does not flow
consistently when drain is at positive

+

pressure.

+

-

-

-

-

Evaporator Coil

Open

+

+

3/4

+

3/4

1/2” CPVC or larger*

+

3/4

+

+

standpipe

3/4” PVC

3/4

+

Condensing

Furnace

+

+

+

+

+

+

3/4

< +

< +

3/4” PVC

+

+

< +

1/2

-

Blower

-

1/2

-

-

-

+ = Positive pressure
< + = Pressure lower than areas with +

− = Negative pressure

-

Fig. 17 -- Example of Field Drain Attachment (Not Allowed)

-

AIRFLOW

OF

DIRECTION

+

+

Evaporator Coil

+

Condensing

Furnace

+

+

+

+

+

+

3/4

< +

< +

3/4” PVC

-

Blower

-

-

-

-

+ = Positive pressure
< + = Pressure lower than areas with +

− = Negative pressure

-

+

< +

+

+

3/4

+

+

3/4

+

+

3/4

+

+

+

+

3/4

+

+

++

3/4” PVC

1/2” CPVC or larger*

3/4

A14532

16

&RLORUKXPLGLILHUGUDLQ
ZKHQXVHG

Air gap here

Open standpipeLQKLJK

PLQLPXP for coilor

humidifier drain
TEE
(1/2” CPVC to 3/4” PVC
adapter from loose parts bag.)

To open drain

ДДДДДДДДДД

Evaporator Coil

ДДДДДДДДДД

ДДДДДДДДДД

ДДДДДДДДДД

+

ДДДДДДДДДД

ДДДДДДДДДД

ДДДДДДДДДД

AIRFLOW

OF

+

DIRECTION

-

+

Condensing

Furnace

+

Blower

-

+

+

-

+ = Positive pressure
< + = Pressure lower than areas with +

ï = Negative pressure

3/4” PVC

3/4

+

+

+

3/4” PVC

3/4

+

Open standpipeLQKLJKPLQLPXP
Air gap required when

+

another drain is connected

+

to furnace drain.

3/4

TEE

< +

3/4

(1/2” CPVC to 3/4” PVC
adapter from loose parts bag.)

< +

< +

-

-

3/4

-

Evaporator Coil

standpipe

Open

DIRECTION OF AIRFLOW

+

+

Condensing

Furnace

+

+

+

+

3/4

+

< +

< + < +

3/4” PVC

+

+

+

3/4

+

+

3/4

3/4

(Optional

when coil drain

not

connected to

drain.)

3/4” PVC

1/2”CPVCorlarger*
Recommend “T” fitting

ZLWKPLQLPXPLQFKhigh
standpipe of same
diameteror larger

H[WHQGLQJXSZDUG

furnace

is

ï

Blower

ï

ï

3/4

ï

ï

ï

= Positive pressure

+
< +

= Pressure lower than areas with +

( = Negative pressure

Fig. 18 -- Example of Field Drain Attachment

INSTALLATION

NOTICE

This furnace is certified to leak 2% or less of nominal air
conditioning CFM delivered when pressurized to 1--in. water
column with all present air inlets, including bottom closure in
upflow and horizontal applications, air outlets, and plumbing
and electrical ports sealed.

Upflow Installation

NOTE: The furnace must be pitched as shown in Fig. 21 for

proper condensate drainage.

Evaporator

ДДДДДДДДД

ДДДДДДДДД

+

ДДДДДДДДД

ДДДДДДДДД

ДДДДДДДДД

ДДДДДДДДД

ДДДДДДДДД

Condensing

+

DIRECTIONOFAIRFLOW

+

Furnace

+

Coil

+

+

3/4” PVC

3/4

+

< +

< +

Open standpipe
(Optional when coil drain is
not connected to furnace
drain.)

3/4

+

3/4

3/4” PVC

TEE

3/4

(1/2” CPVC to 3/4” PVC
adapter from loose parts bag.)

< +

3/4

-

Blower

-

-

-

-

+ = Positive pressure
< + = Pressure lower than areas with +

ï = Negative pressure

-

Supply Air Connections

For a furnace not equipped with a cooling coil, the outlet duct shall
be provided with a removable access panel. This opening shall be
accessible when the furnace is installed and shall be of such a size
that the heat exchanger can be viewed for possible openings using
light assistance or a probe can be inserted for sampling the air
stream. The cover attachment shall prevent leaks.

Connect supply--air duct to flanges on furnace supply--air outlet.
Bend flange upward to 90_ with wide duct pliers. See Fig. 19. The
supply--air duct must be connected to ONLY the furnace
supply--outlet--air duct flanges or air conditioning coil casing
(when used). DO NOT cut main furnace casing side to attach
supply air duct, humidifier, or other accessories. All supply--side
accessories MUST be connected to duct external to furnace main
casing.

3/4

A170135

17

PERFORATED
DISCHARGE DUCT
FLANGE

UPFLOW DOWNFLOW HORIZONTAL

90°

90°

120°

MIN

Fig. 19 -- Duct Flanges

Return Air Connections

!

WARNING

FIRE HAZARD

A failure to follow this warning could cause personal injury,
death and/or property damage.

Never connect return--air ducts to the back of the furnace.
Follow instructions below.

The return--air duct must be connected to bottom, sides (left or
right), or a combination of bottom and side(s) of main furnace
casing. Bypass humidifier may be attached into unused return air
side of the furnace casing. See Fig. 22, 23, and 24.

Bottom Return Air Inlet

These furnaces are shipped with bottom closure panel installed in
bottom return --air opening. Remove and discard this panel when
bottom return air is used. To remove bottom closure panel, see Fig.
27 and 28.

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. Where required by code, seal bottom
closure to furnace with tape, mastic or other durable sealing
method.

NOTE: Side return--air openings can be used in UPFLOW and
some HORIZONTAL configurations. Do not use side return--air
openings in DOWNFLOW configuration. See Fig. 22, 23, and

24.

Leveling Legs (If Desired)

In upflow position with side return inlet(s), leveling legs may be
used. See Fig. 20. Install field--supplied, 5/16 x 1--1/2 in. (8 x 38
mm) (max) corrosion--resistant machine bolts, washers and nuts.

NOTE: Bottom closure must be used when leveling legs are used.
It may be necessary to remove and reinstall bottom closure panel to
install leveling legs. To remove bottom closure panel, see Fig. 27
and 28.

To install leveling legs:

1. Position furnace on its back. Locate and drill a hole in each
bottom corner of furnace.

YES

YES

NO

120°

MIN

YES

YES

NO

120°

MIN

2. For each leg, install nut on bolt and then install bolt with
nut in hole. (Install flat washer if desired.)

3. Install another nut on other side of furnace base. (Install flat
washer if desired.)

4. Adjust outside nut to provide desired height, and tighten in­side nut to secure arrangement.

5. Reinstall bottom closure panel if removed.

5/

16



(8mm)

(8mm)

5/

16



1 3 / 4 

(44mm)

3

1

/ 4 

(44mm)

(8mm)

5

/

16



(8mm)

5/

16



(44mm)

(44mm)

1

3/

4 

3/

1

4 

Fig. 20 -- Leveling Legs

Downflow Installation

NOTE: The furnace must be pitched as shown in Fig. 21 for

proper condensate drainage.

Supply Air Connections

NOTE: For downflow applications, this furnace is approved for

use on combustible flooring when any one of the following
accessories are used:

S Special Base, KGASB
S Cased Coil Assembly Part No. CNPV, CNRV, CAP, or CAR
S Coil Box Part No. KCAKC

YES

YES

NO

A10493

A89014

18

1. Determine application being installed from Ta b l e 8.

2. Construct hole in floor per Table 8andFig. 31.

3. Construct plenum to dimensions specified in Ta b l e 8and
Fig. 31.

4. Install special base coil assembly or coil box as shown in in
Fig. 31.

!

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care
and wear appropriate protective clothing, safety glasses and
gloves when handling parts, and servicing furnaces.

!

WARNING

FIRE, EXPLOSION, AND CARBON MONOXIDE
POISONING HAZARD

Failure to follow this warning could result in personal
injury, death, or property damage.

Do not install the furnace on its back or hang furnace with
control compartment facing downward. Safety control
operation will be adversely affected. Never connect
return--air ducts to the back of the furnace.

!

CAUTION

NOTE: It is recommended that the perforated supply--air duct

flanges be completely removed from furnace when installing the
furnace on a factory--supplied cased coil or coil box. To remove the
supply--air duct flange, use wide duct pliers or hand seamers to
bend flange back and forth until it breaks off. Be careful of sharp
edges. See Fig. 19.

Connect supply--air duct to supply--air outlet on furnace. Bend
flange inward past 90_ with wide duct pliers See Fig. 19. The
supply--air duct must be connected to ONLY the furnace supply
outlet or air conditioning coil casing (when used). When installed
on combustible material, supply--air duct must be connected to
ONLY the factory-- approved accessory subbase, or a
factory-- approved air conditioning coil casing. DO NOT cut main
furnace casing to attach supply side air duct, humidifier, or other
accessories. All supply--side accessories MUST be connected to
duct external to furnace casing.

Return Air Connections

!

WARNING

FIRE HAZARD

A failure to follow this warning could cause personal injury,
death and/or property damage.

Never connect return--air ducts to the back of the furnace.
Follow instructions below.

The return-- air duct must be connected to return--air opening
(bottom inlet). DO NOT cut into casing sides (left or right).
Bypass humidifier connections should be made at ductwork or coil
casing sides exterior to furnace. See Fig. 23.

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 see Fig.
27 and 28.

Horizontal Installation

NOTE: The furnace must be pitched forward as shown in Fig. 21

for proper condensate drainage.

MINOR PROPERTY HAZARD

Failure to follow this caution may result in minor property
damage.

Local codes may require a drain pan under entire furnace and
condensate trap when a condensing furnace is used in an attic
application or over a finished ceiling.

The furnace can be installed horizontally in an attic or crawlspace
on either the left--hand (LH) or right--hand (RH) side. The furnace
can be hung from floor joists, rafters or trusses or installed on a
non--combustible platform, blocks, bricks or pad.

LEVEL 0-IN. (0 MM) TO
1/2-IN. (13 MM) MAX

MIN 1/4-IN. (6 MM) TO
1/2-IN. (13 MM) MAX

UPFLOW OR
DOWNFLOW

Fig. 21 -- Furnace Pitch Requirements

HORIZONTAL

A11237

Platform Furnace Support

Construct working platform at location where all required furnace
clearances are met. See Ta b le 1andFig. 25. For furnaces with
1-- in. (25 mm) clearance requirement on side, set furnace on
non--combustible blocks, bricks or angle iron. For crawlspace
installations, if the furnace is not suspended from the floor joists,
the ground underneath furnace must be level and the furnace set on
blocks or bricks.

Suspended Furnace Support

The furnace must be supported under the entire length of the
furnace with threaded rod and angle iron. See Fig. 26. Secure
angle iron to bottom of furnace as shown.

Roll--Out Protection

Provide a minimum 12--in. x 22--in. (305 x 559 mm) piece of sheet
metal for flame roll--out protection in front of burner area for
furnaces closer than 12-- in. (305 mm) above the combustible deck

19

or suspended furnaces closer than 12--in. (305 mm) to joists. The
sheet metal MUST extend underneath the furnace casing by 1 --in.
(25 mm) with the door removed.

The bottom closure panel on furnaces of widths 17-- 1/2--in. (445
mm) and larger may be used for flame roll--out protection when
bottom of furnace is used for return air connection. See Fig. 25 for
proper orientation of roll--out shield.

ANY COMBINATION OF 1, 2, OR 3 PERMITTED.

A11036

Fig. 22 -- Upflow Return Air Configurations and Restrictions

HORIZONTAL TOP
RETURN NOT
PERMITTED FOR
ANY MODEL

A11038

Fig. 24 -- Horizontal Return Air Configurations

and Restrictions

Supply Air Connections

For a furnace not equipped with a cooling coil, the outlet duct shall
be provided with a removable access panel. This opening shall be
accessible when the furnace is installed and shall be of such a size
that the heat exchanger can be viewed for possible openings using
light assistance or a probe can be inserted for sampling the air
stream. The cover attachment shall prevent leaks.

Connect supply--air duct to flanges on furnace supply--air outlet.
Bend flange upward to 90_ with wide duct pliers. See Fig. 19.
The supply--air duct must be connected to ONLY the furnace
supply--outlet--air duct flanges or air conditioning coil casing
(when used). DO NOT cut main furnace casing side to attach
supply air duct, humidifier, or other accessories. All supply--side
accessories MUST be connected to duct external to furnace main
casing.

Return Air Connections

The return--air duct may be connected to bottom of the furnace.
The side of casing that faces downward may also be used for return
air connection. A combination of the bottom and downward
facing side may also be used. The upward facing side of the casing
cannot be used as a return air connection. See Fig. 24.

Fig. 23 -- Downflow Return Air Configurations

and Restrictions

A11037

20

COMBUSTION - AIR PIPE

T

T

(SEE VENTING SECTION)

30 IN. (762 mm)

2-IN.

(51 mm)

ROLLOUT PROTECTION REQUIRED

Install 12” x 22” (305x559 mm) sheet metal in front of burner compartment
area. The sheet metal MUST extend underneath the furnace casing by 1-in.
(25 mm) with the door removed. The bottom closure panel may be used for
ame roll-out protection when bottom of furnace is used for return air connection.

MIN. WORK AREA

A150580

Fig. 25 -- Working Platform for Attic Installation

NOTE: Local codes may require a drain pan and condensate trap when a condensing furnace is installed over a finished ceiling.

COMBUSTION-AIR PIPE
(SEE VENTING SECTION)

2-IN.

(51 mm)

ROLLOUT PROTECTION REQUIRED

Install 12” x 22” (204 x 559 mm) sheet metal in front of and above the burner compartment area.

he sheet metal MUST extend above the furnace casing by 1-in. (25 mm with the door removed.

A 1-in. (25 mm) clearance minimum between top of furnace and combustible material is required.

he entire length of furnace must be supported when furnace is used in horizontal position to

ensure proper drainage.

NOTE: FURNACE SHOWN IS A DIRECT-VENT APPLICATION. REFER TO THE VENTING SECTION FOR
ALLOWABLE VENT CONFIGURATIONS.

A150581

NOTE: Local codes may require a drain pan and condensate trap when a condensing furnace is installed over a finished ceiling.

Fig. 26 -- Suspended Furnace Installation

21

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 see Fig.
27 and 28.

Side Return Air Inlet

These furnaces are shipped with bottom closure panel installed in
bottom return--air opening. This panel MUST be in place when
side return air inlet(s) are used without a bottom return air inlet.

Not all horizontal furnaces are approved for side return air
connections See Fig. 24. Where required by code, seal bottom
closure to furnace with tape, mastic or other durable sealing
method..

BOTTOM

SCREWS (2)

Representative drawing only,

some models may vary in appearance.

1 Lay furnace on the back or side
2 Remove the two (2) screws that secure the bottom

closure panel tothe furnace casing and remove the
panel

Fig. 27 -- Removing Bottom Closure Panel (2 Screws)

CLOSURE

A170123

Filter Arrangement

!

WARNING

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 filtration device
installed. Never operate a furnace with filter or filtration
device access doors removed.

There are no provisions for an internal filter rack in these furnaces.
An external filter is required.

This furnace may use an optional Media Filter Cabinet available
from your local distributor. The Media Filter Cabinet uses either a
standard 1-inch (25 mm) filter or 4-inch (102 mm) wide Media
Filter which can be purchased separately.

The Media Cabinet is sized for bottom return applications for use
in upflow, downflow and horizontal applications.

For upflow side return applications, the Media Cabinet or field
supplied accessory air cleaner can be installed on the side of the
furnace or side and bottom when a bottom plenum is used. See
Fig. 22 and 30.

For downflow applications, the Media Cabinet or field supplied
accessory air cleaner must only be connected to the bottom
opening on the furnace. See Fig. 23 and 30.

For horizontal applications, the Media Cabinet or field supplied
accessory air cleaner for all models can be connected to the bottom
opening on the furnace. For side return use in the horizontal
position, refer to Fig. 24. If both side and bottom openings are
used in Fig. 24, each opening used will require a filter.

The media cabinet or field supplied accessory air cleaner can also
be installed in the common return duct prior to entering the return
air opening in any orientation.

Refer to the instructions supplied with Media Cabinet or accessory
air filter for assembly and other details.

See Table 7 for filter size details.

Filter and Return Duct Sizing

Pressure drop must be taken into account when sizing filters, filter
racks, IAQ devices, and associated system ductwork. See Table 5
for a comparison of Pressure Drop (initial/clean resistance to
airflow) versus Airflow for a variety of filter media types and sizes.
These are representative numbers. Consult the filter or IAQ device
manufacturers’ specification sheet for performance data for a
particular filter media or IAQ device.

Design the filter and associated ductwork for the best match of
pressure drop versus filter size. Best practice usually chooses filter
systems with pressure drops under 0.2 in. W.C. (50 Pa), with the
best blower electrical efficiency and system airflow performance
occurring with filter pressure drops under 0.1 in. W.C. (25 Pa).

SCREWS (4)

BOTTOM
PLATE

Representative drawing only,

some models may vary in appearance.

1 Lay furnace on the back or side
2 Remove the four (4) screws that secure the bottom

plate to the furnace casing
3 Remove the bottom closure from the casing
4 Re--installthe bottom plateto the furnace casing and

re--install the four (4) screws

A170124

Fig. 28 -- Removing Bottom Closure Panel (4 Screws)

NOTICE

Design the duct system FIRST to determine how much
pressure drop may be allowed in the filter system. See the Air
Ducts section. Excessive filter pressure drop often
compromises system airflow and duct performance, causes
inadequate airflow to the furthest ends of the duct system, as
well as causes excess noise and higher than anticipated
electrical consumption.

Provide duct transitions, as required, to smoothly transition airflow
from the return duct system to the filter (or IAQ device) to the
furnace when the dimensions of the ductwork or furnace return air
opening do not match the required filter or IAQ device dimensions.
See the instructions supplied with factory-- accessory duct adapters.

22

Table 5 – Filter Media Pressure Drop (Clean) Versus Airflow -- In. W.C. (Pa)

14 x 25 Filter

(356 x 635 mm)

CFM L/s (1-in. / 2.5 cm) (4-in. / 10 cm) (1-in. / 2.5 cm) (2-in. / 5 cm) (1-in. / 2.5 cm) (2-in. / 5 cm)

600 (283) 0.04 (12) 0.05 (12) 0.07 (17) 0.10 (26) 0.24 (60) 0.16 (40)
800 (378) 0.06 (15) 0.07 (19) 0.10 (25) 0.15 (39) 0.34 (85) 0.23 (59)

1000 (472) 0.07 (18) 0.10 (27) 0.13 (34) 0.21 (52) - - 0.32 (81)
1200 (566) 0.08 (20) 0.14 (36) 0.17 (43) 0.27 (68) - - - -

Factory-Accessory

Washable

Factory-Accessory

Media*

Representative After-Market Filter Media*

Fiberglass* Pleated*

16 x 25 Filter

(406 x 635 mm)

CFM L/s (1-in. / 2.5 cm) (4-in. / 10 cm) (1-in. / 2.5 cm) (2-in. / 5 cm) (1-in. / 2.5 cm) (2-in. / 5 cm)

600 (283) 0.04 (10) 0.05 (13) 0.06 (15) 0.09 (22) 0.20 (51) 0.13 (34)
800 (378) 0.05 (13) 0.07 (18) 0.08 (21) 0.13 (32) 0.29 (72) 0.20 (49)

1000 (472) 0.06 (16) 0.11 (28) 0.11 (28) 0.17 (43) - - 0.27 (67)
1200 (566) 0.07 (18) 0.15 (37) 0.14 (36) 0.22 (56) - - - ­1400 (661) 0.08 (21) 0.19 (48) 0.18 (45) 0.28 (70) - - - ­1600 (755) 0.09 (23) 0.24 (60) 0.21 (54) - - - - - ­1800 (850) 0.10 (25) - - 0.26 (64) - - - - - -

20 x 25 Filter

(508 x 635 mm)

CFM (L/s) (1-in. / 2.5 cm) (4 -in. / 10 cm) (1-in. / 2.5 cm) (2-in. / 5 cm) (1-in. / 2.5 cm) (2-in. / 5 cm)

800 (378) 0.04 (11) 0.05 (12) 0.06 (16) 0.09 (24) 0.22 (55) 0.15 (37)

1000 (472) 0.05 (13) 0.07 (18) 0.08 (21) 0.13 (32) 0.29 (72) 0.20 (49)
1200 (566) 0.06 (15) 0.09 (22) 0.11 (27) 0.16 (41) - - 0.25 (63)
1400 (661) 0.07 (17) 0.12 (31) 0.13 (33) 0.20 (51) - - 0.31 (79)
1600 (755) 0.08 (19) 0.15 (38) 0.16 (40) 0.24 (61) - - - ­1800 (850) 0.08 (21) 0.18 (47) 0.18 (47) 0.29 (73) - - - ­2000 (944) 0.09 (23) 0.22 (56) 0.21 (54) - - - - - ­2200 (1038) 0.09 (24) 0.26 (66) 0.25 (62) - - - - - -

25 x 25 Filter

(635 x 635 mm)

CFM L/s (1-in. / 2.5 cm) (4-in. / 10 cm) (1-in. / 2.5 cm) (2-in. / 5 cm) (1-in. / 2.5 cm) (2-in. / 5 cm)

800 (378) 0.03 (9) 0.03 (8) 0.05 (12) 0.07 (18) 0.17 (43) 0.11 (28)

1000 (472) 0.04 (11) 0.05 (12) 0.06 (16) 0.09 (24) 0.22 (55) 0.15 (37)
1200 (566) 0.05 (13) 0.07 (17) 0.08 (20) 0.12 (31) 0.27 (68) 0.18 (47)
1400 (661) 0.06 (15) 0.09 (23) 0.10 (24) 0.15 (38) - - 0.23 (58)
1600 (755) 0.06 (16) 0.12 (31) 0.11 (29) 0.18 (45) - - 0.28 (69)
1800 (850) 0.07 (18) 0.14 (35) 0.13 (34) 0.21 (53) - - - ­2000 (944) 0.08 (19) 0.16 (41) 0.16 (39) 0.24 (61) - - - ­2200 (1038) 0.08 (21) 0.19 (49) 0.18 (45) 0.28 (70) - - - -

Factory-Accessory

Washable

Factory-Accessory

Washable

Factory-Accessory

Washable

Factory-Accessory

Media*

Factory-Accessory

Media*

Factory-Accessory

Media*

Representative After-Market Filter Media*

Fiberglass* Pleated*

Representative After-Market Filter Media*

Fiberglass* Pleated*

Representative After-Market Filter Media*

Fiberglass* Pleated*

If the filter size that you are looking for is not contained in Table 5, refer to Table 6 for a comparison of Pressure Drop (initial/clean resistance
to airflow) versus Face V elocity for a variety of filter media types.

The following equations relate Face Velocity (FPM), Filter Area and Airflow (CFM):

Filter Face Velocity = Airflow / Filter Area
Minimum Filter Area = Rated System Airflow / Maximum Filter Face Velocity

Table 6 – Filter Media Pressure Drop (Clean) Versus Face Velocity-- In. W.C. (Pa)

Face Velocity

FPM (m/s) (1-in. / 2.5 cm) (1-in. / 2.5 cm) (2-in. / 5 cm) (1-in. / 2.5 cm) (2-in. / 5 cm)

200 (1) 0.04 (10) 0.05 (13) 0.08 (20) 0.18 (47) 0.12 (31)
300 (1.5) 0.05 (14) 0.09 (22) 0.13 (34) 0.30 (75) 0.21 (52)
400 (2) 0.07 (17) 0.13 (32) 0.20 (50) - - 0.31 (78)
500 (2.5) 0.08 (21) 0.18 (44) 0.27 (69) - - - ­600 (3) 0.09 (23) 0.23 - - - - - - ­700 (3.6) 0.10 (26) 0.29 - - - - - - -

Factory-Accessory

Washable

Representative After-Market Filter Media*

Fiberglass* Pleated*

Table 7 – Air Filter Selection and Duct Sizing -- In. (mm)

FILTER CABINET HEIGHT --- IN (MM) F I L T E R S I Z E --- I N ( M M ) FILTER TYPE

* Recommended to maintain air filter face vel ocity. See Product Data for part number.
{ Not all families have these models.

14---3/16{ (360) 14 x 25 x 3/4 (356 x 635 x 19) Washable or Media*

16 (406)

20 (508)

24 (610)

(1) 16 x 25 x 3/4* (406 x 635 x 19) or

(1) 16 x 25 x 4--- 5/16 (406 x 635 x 110)

(1) 20 x 25 x 3/4* (508 x 635 x 19) or
(1) 20 x 25 x 4--- 5/16 (508 x 635 x 110)
(1) 24 x 25 x 3/4*or (610 x 635 x 19) or
(1) 24 x 25 x 4--- 5/16 (610 x 635 x 110)

Washable or Media*

Washable or Media*

Washable or Media*

23

Air Filter Located in Filter Cabinet

FILTER

CABINET

HEIGHT

IN (MM)

14---3/16{

(360)

16 (406)

21 (533)

24 ½ (622)

* Filters with a side return--- air may have a different filter size. Measure the
filter to obtain the correct size.

* Recommended to maintain air filter face vel ocity. See Product Data for
part number.
{ Not all families have these models.

F I L T E R S I Z E --- I N ( M M ) FILTER TYPE

14 x 25 x 3/4

(356 x 635 x 19)

Washable
or Media*

(1) 16 x 25 x 3/4*

(406 x 635 x 19) or

(1) 16 x 25 x 4--- 5/16

Washable
or Media*

(406 x 635 x 110)

(1) 20 x 25 x 3/4*

(508 x 635 x 19) or

(1) 20 x 25 x 4--- 5/16

Washable
or Media*

(508 x 635 x 110)

(1) 24 x 25 x 3/4*or

(610 x 635 x 19) or

(1) 24 x 25 x 4--- 5/16

Washable
or Media*

(610 x 635 x 110)

14-3/16 and 17-1/2-in.

Furnace

EXAMPLE FOR
UPFLOW INSTALLATIONS.
MAY BE APPLIED TO
OTHER CONFIGURATIONS.

Fig. 29 -- Sample Inlet Air Pipe Connection for Polypropylene

A12220

Ven t ing Syst e ms

4-in.

21-in. Furnace

4-Ton or less, AC

capacity airflow

Block Off
Plate

16-in. Media Cabinet

Media Cabinet Installation

Side Return

21- or 24-1/2-in.

Furnace

Up to 5-Ton AC
capacity airflow

20- or 24-in. Media

Cabinet

Bottom Return Plenum

20- or -24-in. Media Cabinet Installation

for Combination Side and Bottom Return

14-3/16-in. Furnace

Screw

Screw

20-in. Media Cabinet

Media Cabinet Installation Option for

4-Ton or Less A/C Capacity

21-in. Furnace
up to 5-Ton AC
Capacity

24-1/2-in. Furnace
up to 4-Ton AC
Capacity

Transition

20- or 24-in. Media Cabinet

20- or -24-in. Media Cabinet Installation

with Angled Transition

14-3/16-in. Furnace

Screws

1/2-in.

Screws

45°

Filler plates

14--3/16-in. Furnacewith Filler Plates, Centered

Fig. 30 -- Optional Media Filter

Filler plate

14--3/16-in. Furnacewith Filler Plates, O ff-- Set to Right

A11437

24

FURNACE

(OR COIL CASING

WHEN USED)

FURNACE

APPROVED

COIL ASSEMBLY

OR

COIL BOX

A

PLENUM

FURNACE

CASING

WIDTH

IN. (mm)

OPENING

B

FLOOR

OPENING

C

D

Upflow Applications on Combustible or Noncombustible

Downflow Applications on Noncombustible Flooring

14–3/16{

(360)

Downflow applications on combustible flooring

Downflow Applications on Combustible Flooring with coil

assembly or coil box (subbase not required)

Upflow Applications on Combustible or Noncombustible

Downflow Applications on Noncombustible Flooring

17–1/2

(445)

Downflow applications on combustible flooring

Downflow Applications on Combustible Flooring with coil

assembly or coil box (subbase not required)

Upflow Applications on Combustible or Noncombustible

Downflow Applications on Noncombustible Flooring

21

(533)

Downflow applications on combustible flooring

Downflow Applications on Combustible Flooring with coil

assembly or coil box (subbase not required)

Upflow Applications on Combustible or Noncombustible

Downflow Applications on Noncombustible Flooring

24---1/2

(622)

* Not all families have these models.

Downflow applications on Combustible flooring

Downflow Applications on Combustible Flooring with coil

assembly or coil box (subbase not required)

Fig. 31 -- Installation on Combustible Flooring

Table 8 – Opening Dimensions -- In. (mm)

APPLICATION

Flooring (subbase not required)

(subbase not required)

(subbase required)

Flooring (subbase not required)

(subbase not required)

(subbase required)

Flooring (subbase not required)

(subbase not required)

(subbase required)

Flooring (subbase not required)

(subbase not required)

(subbase required)

COMBUSTIBLE

FLOORING

DOWNFLOW

SUBBASE

SHEET METAL

PLENUM

FLOOR

OPENING

COMBUSTIBLE

FLOORING

SHEET METAL

PLENUM

FLOOR

OPENING

PLENUM OPENING FLOOR OPENING

A B C D

12---11/16

(322)

12---9/16

(319)

11---13/16

(284)

12---5/16

(319)

16

(406)

15---7/8

(403)

15---1/8

(384)

15---1/2

(394)

19---1/2

(495)

19---3/8

(492)

18---5/8

(473)

19

(483)

23

(584)

22---7/8

(581)

22---1/8

(562)

22---1/2

(572)

21---5/8

(549)

19

(483)

19

(483)

19

(483)

21---5/8

(549)

19

(483)

19

(483)

19

(483)

21---5/8

(549)

19

(483)

19

(483)

19

(483)

21---1/8

(537)

19

(483)

19

(483)

19

(483)

13---5/16

(338)

13---3/16

(335)

13---7/16

(341)

13---5/16

(338)

16---5/8

(422)

16---1/2

(419)

16---3/4

(425)

16---1/2

(419)

20---1/8

(511)

20

(508)

20---1/4

(514)

20

(508)

23---5/8

(600)

23---1/2

(597)

23---3/4

(603)

23---1/2

(597)

A10491

22---1/4

(565)

19---5/8

(498)

20---5/8

(600)

20

(508)

22---1/4

(565)

19---5/8

(498)

20---5/8

(600)

20

(508)

22---1/4

(565)

19---5/8

(498)

20---5/8

(600)

20

(508)

22---1/4

(565)

19---5/8

(498)

20---5/8

(600)

20

(508)

25

Table9–Cooling4and Heating Air Delivery -- CFM (Bottom Return5with Filter)

( S W 1 --- 5 a n d S W 4 --- 3 s e t t o O F F, e x c e p t a s i n d i c a t e d . S e e n o t e s 1 a n d 2 . )

Unit Size:

30040V14

Clg Switches: S W 2 --- 8 S W 2 --- 7 S W 2 --- 6 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1125 1105 1080 1055 1030 1005 975 955 930 905

Cooling (SW2 --- 8,7,6)

CF Switches S W 2 --- 5 SW 2 --- 4 S W 2 --- 3

L o w --- C l g D e f a u l t : OFF OFF OFF 605 565 525 485 445 Seenote4

L o w --- C o o l i n g

(SW2---5,4,3)

Cont. Fan Default: OFF OFF OFF 385 335 SeeNote4

Continuous Fan

(SW2---5,4,3)

Heating (SW1)

Clg/CF Switch settings External Static Pressure (ESP)

OFF OFF ON 605 565 525 485 445 Seenote4
OFF ON OFF 760 730 695 655 625 590 555 525 490 455
OFF ON ON 950 925 900 870 840 810 785 760 730 705

ON OFF OFF 1125 1105 1080 1055 1030 1005 975 955 930 905
ON OFF ON 1130 1105 1080 1055 1030 1005 980 955 930 905
ON ON OFF 1130 1105 1080 1055 1030 1005 980 955 930 905
ON ON ON 1130 1105 1080 1055 1030 1005 980 955 930 905

Maximum Clg Airflow

2

1130 1105 1080 1055 1030 1005 980 955 930 905

OFF OFF ON 605 565 525 485 445 Seenote4
OFF ON OFF 760 730 695 655 625 590 555 525 490 455
OFF ON ON 950 925 900 870 840 810 785 760 730 705

ON OFF OFF 1125 1105 1080 1055 1030 1005 975 955 930 905
ON OFF ON 1130 1105 1080 1055 1030 1005 980 955 930 905
ON ON OFF 1130 1105 1080 1055 1030 1005 980 955 930 905
ON ON ON 1130 1105 1080 1055 1030 1005 980 955 930 905

OFF OFF ON 245 180 SeeNote4
OFF ON OFF 310 245 SeeNote4
OFF ON ON 385 335 SeeNote4

ON OFF OFF 385 335 SeeNote4
ON OFF ON 385 335 SeeNote4
ON ON OFF 385 335 SeeNote4
ON ON ON 385 335 SeeNote4

High Heat Airflow

Low Heat Airflow

3

3

800 770 730 700 665 635 605 570 540 510
560 520 470 425 390 Seenote4

Unit Size:

36040V17

Clg/CF Switch settings External Static Pressure (ESP)

Clg Switches: S W 2 --- 8 S W 2 --- 7 S W 2 --- 6 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1240 1210 1180 1145 1105 1060 1005 950 895 835

OFF OFF ON 585 540 490 445 400 360 315 265 210 155
OFF ON OFF 780 740 695 655 620 580 545 510 480 445
OFF ON ON 975 945 910 870 835 805 775 740 710 680

Cooling (SW2 --- 8,7,6)

ON OFF OFF 1170 1140 1115 1085 1050 1020 985 945 890 835
ON OFF ON 1240 1210 1180 1145 1105 1060 1005 950 895 835
ON ON OFF 1240 1210 1180 1145 1105 1060 1005 950 895 835
ON ON ON 1240 1210 1180 1145 1105 1060 1005 950 895 835

Maximum Clg Airflow

2

1240 1210 1180 1145 1105 1060 1005 950 895 835

CF Switches S W 2 --- 5 SW 2 --- 4 S W 2 --- 3

L o w --- C l g D e f a u l t : OFF OFF OFF 585 540 490 445 400 Seenote4

OFF OFF ON 585 540 490 445 400 Seenote4
OFF ON OFF 780 740 695 655 620 580 545 510 480 445

L o w --- C o o l i n g

(SW2---5,4,3)

OFF ON ON 975 945 910 870 835 805 775 740 710 680

ON OFF OFF 1170 1140 1115 1085 1050 1020 985 945 890 835
ON OFF ON 1240 1210 1180 1145 1105 1060 1005 950 895 835
ON ON OFF 1240 1210 1180 1145 1105 1060 1005 950 895 835
ON ON ON 1240 1210 1180 1145 1105 1060 1005 950 895 835

Cont. Fan Default: OFF OFF OFF 585 540 490 445 400 Seenote4

OFF OFF ON 305 235 SeeNote4
OFF ON OFF 470 410 350 SeeNote4

Continuous Fan

(SW2---5,4,3)

OFF ON ON 585 540 490 445 400 Seenote4

ON OFF OFF 585 540 490 445 400 Seenote4
ON OFF ON 585 540 490 445 400 Seenote4
ON ON OFF 585 540 490 445 400 Seenote4
ON ON ON 585 540 490 445 400 Seenote4

Heating (SW1)

High Heat Airflow

Low Heat Airflow

3

3

850 810 770 730 700 660 630 595 560 530
625 580 535 490 445 405 365 320 270 220

26

Table 9 -- Cooling4and Heating Air Delivery -- CFM (Bottom Return5with Filter) continued

( S W 1 --- 5 a n d S W 4 --- 3 s e t t o O F F, e x c e p t a s i n d i c a t e d . S e e n o t e s 1 a n d 2 . )

Unit Size:

36060V14

Clg Switches: S W 2 --- 8 S W 2 --- 7 S W 2 --- 6 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1180 1150 1130 1100 1075 1045 1020 995 965 935

Cooling (SW2 --- 8,7,6)

CF Switches S W 2 --- 5 S W 2 --- 4 S W 2 --- 3

L o w --- C l g D e f a u l t : OFF OFF OFF 625 585 540 495 445 Seenote4

L o w --- C o o l i n g

(SW2---5,4,3)

Cont. Fan Default: OFF OFF OFF 375 315 SeeNote4

Continuous Fan

(SW2---5,4,3)

Heating (SW1)

Clg/CF Switch settings External Static Pressure (ESP)

OFF OFF ON 625 585 540 495 445 Seenote4
OFF ON OFF 820 785 745 710 670 635 595 560 525 490
OFF ON ON 1000 970 935 905 875 845 815 785 755 725

ON OFF OFF 1180 1150 1130 1100 1075 1045 1020 995 965 935
ON OFF ON 1220 1195 1170 1140 1115 1090 1065 1035 1010 985
ON ON OFF 1220 1195 1170 1140 1115 1090 1065 1035 1010 985
ON ON ON 1220 1195 1170 1140 1115 1090 1065 1035 1010 985

Maximum Clg Airflow

2

1220 1195 1170 1140 1115 1090 1065 1035 1010 985

OFF OFF ON 625 585 540 495 445 Seenote4
OFF ON OFF 820 785 745 710 670 635 595 560 525 490
OFF ON ON 1000 970 935 905 875 845 815 785 755 725

ON OFF OFF 1180 1150 1130 1100 1075 1045 1020 995 965 935
ON OFF ON 1220 1195 1170 1140 1115 1090 1065 1035 1010 985
ON ON OFF 1220 1195 1170 1140 1115 1090 1065 1035 1010 985
ON ON ON 1220 1195 1170 1140 1115 1090 1065 1035 1010 985

OFF OFF ON 200 125 SeeNote4
OFF ON OFF 285 215 SeeNote4
OFF ON ON 375 315 SeeNote4

ON OFF OFF 375 315 SeeNote4
ON OFF ON 375 315 SeeNote4
ON ON OFF 375 315 SeeNote4
ON ON ON 375 315 SeeNote4

High Heat Airflow

Low Heat Airflow

3

3

1115 1090 1060 1035 1010 980 955 930 905 875

780 740 695 655 615 575 530 490 450 405

Unit Size:

42060V17

Clg/CF Switch settings External Static Pressure (ESP)

Clg Switches: S W 2 --- 8 S W 2 --- 7 S W 2 --- 6 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1330 1295 1260 1220 1190 1150 1110 1075 1045 1005

OFF OFF ON 725 600 435 280 210 Seenote4
OFF ON OFF 780 725 660 615 540 Seenote4
OFF ON ON 975 925 875 835 785 750 690 655 610 570

Cooling (SW2 --- 8,7,6)

ON OFF OFF 1160 1120 1090 1045 1010 970 920 885 840 800
ON OFF ON 1330 1295 1260 1220 1190 1150 1110 1075 1045 1005
ON ON OFF 1705 1650 1595 1545 1475 1415 1340 1275 1200 1105
ON ON ON 1705 1650 1595 1545 1475 1415 1340 1275 1200 1105

Maximum Clg Airflow

2

1705 1650 1595 1545 1475 1415 1340 1275 1200 1105

CF Switches S W 2 --- 5 S W 2 --- 4 S W 2 --- 3

L o w --- C l g D e f a u l t : OFF OFF OFF 725 600 435 280 210 Seenote4

OFF OFF ON 725 600 435 280 210 Seenote4
OFF ON OFF 780 725 660 615 540 Seenote4

L o w --- C o o l i n g

(SW2---5,4,3)

OFF ON ON 975 925 875 835 785 750 690 655 610 570

ON OFF OFF 1160 1120 1090 1045 1010 970 920 885 840 800
ON OFF ON 1330 1295 1260 1220 1190 1150 1110 1075 1045 1005
ON ON OFF 1705 1650 1595 1545 1475 1415 1340 1275 1200 1105
ON ON ON 1705 1650 1595 1545 1475 1415 1340 1275 1200 1105

Cont. Fan Default: OFF OFF OFF 725 600 435 280 210 Seenote4

OFF OFF ON 725 600 435 280 210 Seenote4
OFF ON OFF 780 725 660 615 540 Seenote4

Continuous Fan

(SW2---5,4,3)

OFF ON ON 975 925 875 835 785 750 690 655 610 570

ON OFF OFF 975 925 875 835 785 750 690 655 610 570
ON OFF ON 975 925 875 835 785 750 690 655 610 570
ON ON OFF 975 925 875 835 785 750 690 655 610 570
ON ON ON 975 925 875 835 785 750 690 655 610 570

Heating (SW1)

High Heat Airflow

Low Heat Airflow

3

3

1145 1105 1075 1030 995 955 905 870 825 785

870 820 760 720 655 620 560 525 470 435

27

Table 9 -- Cooling4and Heating Air Delivery -- CFM (Bottom Return5with Filter) continued

( S W 1 --- 5 a n d S W 4 --- 3 s e t t o O F F, e x c e p t a s i n d i c a t e d . S e e n o t e s 1 a n d 2 . )

Unit Size:

48080V17

Clg Switches: S W 2 --- 8 S W 2 --- 7 S W 2 --- 6 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1595 1560 1530 1500 1470 1440 1405 1370 1340 1290

Cooling (SW2 --- 8,7,6)

CF Switches S W 2 --- 5 S W 2 --- 4 S W 2 --- 3

L o w --- C l g D e f a u l t : OFF OFF OFF 625 555 495 425 360 300 SeeNote4

L o w --- C o o l i n g

(SW2---5,4,3)

Cont. Fan Default: OFF OFF OFF 625 555 495 425 360 300 SeeNote4

Continuous Fan

(SW2---5,4,3)

Heating (SW1)

Clg/CF Switch settings External Static Pressure (ESP)

OFF OFF ON 625 555 495 425 360 300 SeeNote4
OFF ON OFF 810 755 700 645 595 540 480 425 380 330
OFF ON ON 1040 995 950 900 860 815 770 725 680 630

ON OFF OFF 1215 1175 1135 1095 1055 1015 975 935 900 860
ON OFF ON 1390 1355 1320 1285 1245 1210 1175 1140 1105 1070
ON ON OFF 1595 1560 1530 1500 1470 1440 1405 1370 1340 1290
ON ON ON 1790 1760 1735 1700 1655 1610 1570 1485 1395 1295

Maximum Clg Airflow

2

1790 1760 1735 1700 1655 1610 1570 1485 1395 1295

OFF OFF ON 625 555 495 425 360 300 SeeNote4
OFF ON OFF 810 755 700 645 595 540 480 425 380 330
OFF ON ON 1040 995 950 900 860 815 770 725 680 630

ON OFF OFF 1215 1175 1135 1095 1055 1015 975 935 900 860
ON OFF ON 1390 1355 1320 1285 1245 1210 1175 1140 1105 1070
ON ON OFF 1595 1560 1530 1500 1470 1440 1405 1370 1340 1290
ON ON ON 1790 1760 1735 1700 1655 1610 1570 1485 1395 1295

OFF OFF ON 465 390 300 SeeNote4
OFF ON OFF 625 555 495 425 360 300 SeeNote4
OFF ON ON 690 630 570 510 445 385 SeeNote4

ON OFF OFF 690 630 570 510 445 385 SeeNote4
ON OFF ON 690 630 570 510 445 385 SeeNote4
ON ON OFF 690 630 570 510 445 385 SeeNote4
ON ON ON 690 630 570 510 445 385 SeeNote4

High Heat Airflow

Low Heat Airflow

3

3

1470 1435 1400 1365 1330 1295 1260 1225 1190 1155
1150 1110 1070 1030 990 950 910 870 830 790

Unit Size:

60080V21

Clg/CF Switch settings External Static Pressure (ESP)

Clg Switches: S W 2 --- 8 S W 2 --- 7 S W 2 --- 6 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1905 1870 1825 1785 1750 1700 1665 1625 1560 1460

OFF OFF ON 950 770 620 515 440 365 SeeNote4
OFF ON OFF 1015 935 880 825 765 690 625 580 See note
OFF ON ON 1155 1105 1040 990 920 875 815 755 710 645

Cooling (SW2 --- 8,7,6)

ON OFF OFF 1335 1290 1245 1190 1145 1085 1040 990 930 890
ON OFF ON 1520 1485 1435 1390 1340 1300 1255 1200 1160 1115
ON ON OFF 1905 1870 1825 1785 1750 1700 1665 1625 1560 1460
ON ON ON 2290 2230 2160 2085 2005 1915 1820 1730 1640 1525

Maximum Clg Airflow

2

2290 2230 2160 2085 2005 1915 1820 1730 1640 1525

CF Switches S W 2 --- 5 S W 2 --- 4 S W 2 --- 3

L o w --- C l g D e f a u l t : OFF OFF OFF 950 770 620 515 440 365 SeeNote4

OFF OFF ON 645 540 435 SeeNote4
OFF ON OFF 950 770 620 515 440 365 SeeNote4

L o w --- C o o l i n g

(SW2---5,4,3)

OFF ON ON 1015 935 880 825 765 690 625 580 See note

ON OFF OFF 1155 1105 1040 990 920 875 815 755 710 645
ON OFF ON 1335 1290 1245 1190 1145 1085 1040 990 930 890
ON ON OFF 1520 1485 1435 1390 1340 1300 1255 1200 1160 1115
ON ON ON 1905 1870 1825 1785 1750 1700 1665 1625 1560 1460

Cont. Fan Default: OFF OFF OFF 950 770 620 515 440 365 SeeNote4

OFF OFF ON 645 540 435 SeeNote4
OFF ON OFF 950 770 620 515 440 365 SeeNote4

Continuous Fan

(SW2---5,4,3)

OFF ON ON 1015 935 880 825 765 690 625 580 See note

ON OFF OFF 1155 1105 1040 990 920 875 815 755 710 645
ON OFF ON 1335 1290 1245 1190 1145 1085 1040 990 930 890
ON ON OFF 1520 1485 1435 1390 1340 1300 1255 1200 1160 1115
ON ON ON 1520 1485 1435 1390 1340 1300 1255 1200 1160 1115

Heating (SW1)

High Heat Airflow

Low Heat Airflow

3

3

1575 1535 1485 1445 1400 1350 1310 1260 1215 1170
1230 1170 1125 1065 1015 955 900 855 795 755

28

Table 9 -- Cooling4and Heating Air Delivery -- CFM (Bottom Return5with Filter) continued

( S W 1 --- 5 a n d S W 4 --- 3 s e t t o O F F, e x c e p t a s i n d i c a t e d . S e e n o t e s 1 a n d 2 . )

Unit Size:

60100V21

Clg Switches: S W 2 --- 8 S W 2 --- 7 S W 2 --- 6 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 1890 1845 1800 1755 1700 1655 1610 1560 1510 1460

Cooling (SW2 --- 8,7,6)

CF Switches S W 2 --- 5 S W 2 --- 4 S W 2 --- 3

L o w --- C l g D e f a u l t : OFF OFF OFF 1015 825 630 485 405 325 SeeNote4

L o w --- C o o l i n g

(SW2---5,4,3)

Cont. Fan Default: OFF OFF OFF 1015 825 630 485 405 325 SeeNote4

Continuous Fan

(SW2---5,4,3)

Heating (SW1)

Clg/CF Switch settings External Static Pressure (ESP)

OFF OFF ON 1015 825 630 485 405 325 SeeNote4
OFF ON OFF 1080 895 815 740 690 615 555 475 See note
OFF ON ON 1155 1080 1020 940 890 825 785 710 660 590

ON OFF OFF 1310 1260 1195 1140 1075 1025 970 925 875 810
ON OFF ON 1520 1475 1425 1365 1315 1255 1210 1155 1110 1055
ON ON OFF 1890 1845 1800 1755 1700 1655 1610 1560 1510 1460
ON ON ON 2290 2230 2160 2085 2005 1915 1820 1730 1640 1525

Maximum Clg Airflow

2

2290 2230 2160 2085 2005 1915 1820 1730 1640 1525

OFF OFF ON 745 640 535 SeeNote4
OFF ON OFF 1015 825 630 485 405 325 SeeNote4
OFF ON ON 1080 895 815 740 690 615 555 475 See note

ON OFF OFF 1155 1080 1020 940 890 825 785 710 660 590
ON OFF ON 1310 1260 1195 1140 1075 1025 970 925 875 810
ON ON OFF 1520 1475 1425 1365 1315 1255 1210 1155 1110 1055
ON ON ON 1890 1845 1800 1755 1700 1655 1610 1560 1510 1460

OFF OFF ON 745 640 535 SeeNote4
OFF ON OFF 1015 825 630 485 405 325 SeeNote4
OFF ON ON 1080 895 815 740 690 615 555 475 See note

ON OFF OFF 1155 1080 1020 940 890 825 785 710 660 590
ON OFF ON 1155 1080 1020 940 890 825 785 710 660 590
ON ON OFF 1155 1080 1020 940 890 825 785 710 660 590
ON ON ON 1155 1080 1020 940 890 825 785 710 660 590

High Heat Airflow

Low Heat Airflow

3

3

1905 1865 1825 1775 1730 1685 1640 1590 1545 1490
1480 1435 1375 1330 1265 1215 1160 1115 1060 1005

Unit Size:

66120V24

Clg/CF Switch settings External Static Pressure (ESP)

Clg Switches: S W 2 --- 8 S W 2 --- 7 S W 2 --- 6 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0

Clg Default: OFF OFF OFF 2060 2015 1975 1930 1885 1840 1790 1750 1705 1630

OFF OFF ON 865 775 690 595 505 425 SeeNote4
OFF ON OFF 1080 1005 935 860 785 705 625 555 490 425
OFF ON ON 1285 1220 1150 1085 1020 960 895 820 750 690

Cooling (SW2 --- 8,7,6)

ON OFF OFF 1465 1410 1350 1285 1230 1175 1115 1060 1000 935
ON OFF ON 1685 1635 1585 1530 1475 1420 1375 1325 1270 1225
ON ON OFF 2060 2015 1975 1930 1885 1840 1790 1750 1705 1630
ON ON ON 2265 2225 2180 2145 2100 2060 2010 1895 1770 1645

Maximum Clg Airflow

2

2320 2310 2270 2230 2190 2135 2020 1895 1770 1645

CF Switches S W 2 --- 5 S W 2 --- 4 S W 2 --- 3

L o w --- C l g D e f a u l t : OFF OFF OFF 865 775 690 595 505 425 SeeNote4

OFF OFF ON 585 470 SeeNote4
OFF ON OFF 865 775 690 595 505 425 SeeNote4

L o w --- C o o l i n g

(SW2---5,4,3)

OFF ON ON 1080 1005 935 860 785 705 625 555 490 425

ON OFF OFF 1285 1220 1150 1085 1020 960 895 820 750 690
ON OFF ON 1465 1410 1350 1285 1230 1175 1115 1060 1000 935
ON ON OFF 1685 1635 1585 1530 1475 1420 1375 1325 1270 1225
ON ON ON 2060 2015 1975 1930 1885 1840 1790 1750 1705 1630

Cont. Fan Default: OFF OFF OFF 865 775 690 595 505 425 SeeNote4

OFF OFF ON 585 470 SeeNote4
OFF ON OFF 730 630 SeeNote4

Continuous Fan

(SW2---5,4,3)

OFF ON ON 865 775 690 595 505 425 SeeNote4

ON OFF OFF 865 775 690 595 505 425 SeeNote4
ON OFF ON 865 775 690 595 505 425 SeeNote4
ON ON OFF 865 775 690 595 505 425 SeeNote4
ON ON ON 865 775 690 595 505 425 SeeNote4

Heating (SW1)

NOTE: See notes at end of table.

High Heat Airflow

Low Heat Airflow

3

3

2165 2120 2075 2030 1985 1940 1895 1850 1770 1645
1675 1625 1575 1525 1475 1425 1375 1325 1275 1225

29

Tabl e 9 -- Cooling4and Heating Air Delivery -- CFM (Bottom Return5with Filter) -- NOTES

1. Nominal 350 CFM/ton cooling airf low is delivered with SW1 - -- 5 and SW4 ---3 set to OFF.
Set both SW1--- 5 to ON for nominal 400CFM/ton (+15% airflow)
S e t S W 4 --- 3 t o O N f o r n o min a l 32 5 C F M / t on ( --- 7% a i r f l o w )
Set both SW1--- 5 and SW4 ---3 to ON for nominal 370C FM/ton (+7% airflow)
The above adjustments in airflow are subject to motor horsepower range/capacity
This applies to Cooling and Low--- Cooling airflow, but does not affect continuous fan airflow.

2 . M ax i m u m c oo l i n g a ir f l o w i s a c h i ev e d w h en s w i t c h e s S W 2 --- 6 , S W 2 --- 7 , S W 2 --- 8 a n d S W1 --- 5 a r e s e t t o O N , a n d S W 4 --- 3 is s et t o O F F.

3. All heating CFM’s are when comfort/efficiency adjustment switch SW1-- -4 is set to OFF.

4. Ductwork must be sized for high --- heating CFM within the operational range of ESP. Operation within the blank areas of the chart is not recommended be­cause high -- -heat oper ation will be above 1.0 ESP.

5. All airflows on 21” ( 533 mm) casing size furn a ces are 5% less on side ---return onl y installations.

6. Side r etu rns for 24.5” (622 mm) casing sizes require two sides, or a side and bottom to allow suff icient airflow at the r eturn of the furnace.

7. Airflows over 1800 CFM require bottom return, two ---side return, or bottom and side return or excessive watt draw may result. A minimum filter size of
20x25” (508 x 635 mm) is required.

AIR DUCTS

NOTICE

Many states, provinces and localities are considering or have
implemented standards and/or restrictions on duct sizing
practices, ductwork leakage, and/or ductwork thermal, airflow
and electrical efficiencies. CONSULT LOCAL CODE
OFFICIALS for ductwork design and performance
requirements in your area.

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 Manual D), Sheet
Metal and Air Conditioning Contractors National Association
(SMACNA) or American Society of Heating, Refrigerating and
Air Conditioning Engineers (ASHRAE) or consult The Air
Systems Design Guidelines reference tables available from your
local distributor. The duct system should be sized to handle the
required system design CFM at the design external static pressure.
The furnace airflow rates are provided in Ta b l e 9--Air
Delivery--CFM (With Filter). When a furnace is installed so that
the supply ducts carry air circulated by the furnace to areas outside
the space containing the furnace, the return air shall also be
handled by duct(s) sealed to the furnace casing and terminating
outside the space containing the furnace.

Secure ductwork with proper fasteners for type of ductwork used.
Seal supply-- and return --duct connections to furnace with code
approved tape or duct sealer.

NOTE: Flexible connections should be used between ductwork
and furnace to prevent transmission of vibration.

Ductwork passing through unconditioned space should be
insulated to enhance system performance. When air conditioning is
used, a vapor barrier is recommended.

Maintain a 1--in. (25 mm) clearance from combustible materials to
supply air ductwork for a distance of 36-- in. (914 mm) horizontally
from the furnace. See NFPA 90B or local code for further
requirements.

Return Duct Sizing

Refer to the Filter Selection and Duct Sizing section for
information on the proper selection of filter sizes and the associated
ductwork and duct transitions. Improperly designed filtering
systems and return ductwork are the most common causes of
airflow and/or noise complaints in HVAC systems.

Ductwork Acoustical Treatment

NOTE: Metal duct systems that do not have a 90 degree elbow

and 10 ft. (3 M) of main duct to the first branch take--off may
require internal acoustical lining. As an alternative, fibrous
ductwork may be used if constructed and installed in accordance
with the latest edition of SMACNA construction standard on

fibrous glass ducts. Both acoustical lining and fibrous ductwork
shall comply with NFPA 90B as tested by UL Standard 181 for
Class 1 Rigid air ducts.

NOTE: For horizontal applications, the top most flange may be
bent past 90_ to allow the evaporator coil to hang on the flange
temporarily while the remaining attachment and sealing of the coil
are performed.

GAS PIPING

!

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal
injury, death, and/or property damage.

Never purge a gas line into a combustion chamber. Never
test for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection
of leaks to check all connections. A fire or explosion may
result causing property damage, personal injury or loss of
life.

!

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal
injury, death, and/or property damage.

Use proper length of pipe to avoid stress on gas control
manifold and gas valve.

!

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal
injury, death, and/or property damage.

Gas valve inlet and/or inlet pipe must remain capped until
gas supply line is permanently installed to protect the valve
from moisture and debris. Also, install a sediment trap in the
gas supply piping at the inlet to the gas valve.

Gas piping must be installed in accordance with national and local
codes. Refer to current edition of NFGC in the USA. Refer to
current edition of NSCNGPIC in Canada.

Installations must be made in accordance with all authorities
having jurisdiction. If possible, the gas supply line should be a
separate line running directly from meter to furnace.

30

NOTE: Use a back--up wrench on the inlet of the gas valve when
connecting the gas line to the gas valve.

GAS

SUPPLY

NOTICE

In the state of Massachusetts:

1. Gas supply connections MUST be performed by a licensed
plumber or gas fitter.

2. When flexible connectors are used, the maximum length
shall not exceed 36 in. (915 mm).

3. When lever handle type manual equipment shutoff valves
are used, they shall be T --handle valves.

4. The use of copper tubing for gas piping is NOT approved
by the state of Massachusetts.

Refer to Table 10 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 one hanger
every 6 ft. (2 M). Joint compound (pipe dope) should be applied
sparingly and only to male threads of joints. Pipe dope must be
resistant to the action of propane gas.

Table 10 – Maximum Capacity of Pipe

NOMINAL

IRON PIPE

SIZE

IN. (MM)

1/2 (13) 175 120 97 82 73
3/4 (19) 360 250 200 170 151

1 ( 25) 680 465 375 320 285
1-1/4 (32) 1400 950 770 660 580
1-1/2 (39) 2100 1460 1180 990 900

* Cubic ft of gas per hr fo r gas pressures of 0.5 psig (14-- -In. W.C.) or less and
a pressure drop of 0.5 --- In. W.C. (based on a 0.60 specific gravity gas). Ref:
Table 10 above and 6.2 of current edition of NFPA54/ANSI Z223.1.

(3.0)20(6.0)30(9.1)40(12.1)50(15.2)

!

FIRE OR EXPLOSION HAZARD

A failure to follow this warning could result in personal

injury, death, and/or property damage.

If local codes allow the use of a flexible gas appliance

connector, always use a new listed connector. Do not use a

connector which has previously served another gas

appliance. Black iron pipe shall be installed at the furnace

gas control valve and extend a minimum of 2--in. (51 mm)

outside the furnace.

!

FURNACE DAMAGE HAZARD

Failure to follow this caution may result in furnace damage.

Connect gas pipe to furnace using a backup wrench to
avoid damaging gas controls and burner misalignment.

An accessible manual equipment shutoff valve MUST be installed
external to furnace casing and within 6 ft. (2 M) of furnace.

Install a sediment trap externally in the riser leading to furnace as
shown in Fig. 32. 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.

LENGTH OF PIPE --- FT (M)

10

WARNING

CAUTION

FRONT

MANUAL
SHUT OFF
VALV E
(REQUIRED)

SEDIMENT
TRAP

UNION

NOTE: Union may be inside the
vestibule where permitted by
local codes.

A11035

Fig. 32 -- Typical Gas Pipe Arrangement

A 1/8--in. (3 mm) NPT plugged tapping, accessible for test gauge
connection, MUST be installed immediately upstream of gas
supply connection to furnace and downstream of manual
equipment shutoff valve.

Piping should be pressure and leak tested in accordance with the
current addition of the NFGC in the United States, local, and
national plumbing and gas codes before the furnace has been
connected. Refer to current edition of NSCNGPIC in Canada.
After all connections have been made, purge lines and check for
leakage at furnace prior to operating furnace.

NOTE: The furnace gas control valve inlet pressure tap
connection is suitable to use as test gauge connection providing
test pressure DOES NOT exceed maximum 0.5 psig (14--In. W.C.)
stated on gas control valve. See Fig. 33.

INLET PRESSURE TAP

SET SCREW: 3/32” HEX HEAD

ACCEPTS 5/16” HOSE

CONNECTION

1/2” NPT

INLET

MANIFOLD PRESSURE TAP SET SCREW:

3/32” HEX HEAD ACCEPTS
5/16” HOSE CONNECTION

OUTP

ON/OFF SWITCH

Representative drawing only, some models may vary in appearance.

REGULATOR SEAL CAP
(REGULAR ADJ. UNDER CAP)

1/2” NPT

OUTLET

A170117

Fig. 33 -- Gas Valve with Tower Pressure Ports

If pressure exceeds 0.5 psig (14-- In. W.C.), gas supply pipe must be
disconnected from furnace and capped before and during supply
pipe pressure test. If test pressure is equal to or less than 0.5 psig
(14--In. W.C.), turn off electric shutoff switch located on furnace
gas control valve and accessible manual equipment shutoff valve
before and during supply pipe pressure test. After all connections
have been made, purge lines and check for leakage at furnace prior
to operating furnace.

The gas supply pressure shall be within the maximum and
minimum inlet supply pressures marked on the rating plate with
the furnace burners ON and OFF.

Gas entry can be from left or right side, or top panel. See Figs. 34
and 35.

31

Gas Pipe Grommet

For direct vent (2-pipe) applications, the knockout for the gas pipe
must be sealed to prevent air leakage. Remove the knockout, install
the grommet in the knockout, then insert the gas pipe. The
grommet is included in the loose parts bag. See Fig. 34.

Left Side Gas Entry. Gas Pipe
Grommet Required For Direct
Vent Applications.

Gas Pipe Grommet Required
For Direct Vent Applications

!

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal
injury or death.

Blower door switch opens 115--v power to control. No
component operation can occur. Do not bypass or close
switch with blower door removed.

See Fig. 39 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.

A11338

Fig. 34 -- Gas Entry

1ï1/2 inch for Gas

7/8 inch for 115 VAC Electric

A170125

Fig. 35 -- Alternate Gas and Electric Entry

NOTE: Top plate may be field drilled for alternate gas and

115 VAC electric entry.

ELECTRICAL CONNECTIONS

!

WARNING

ELECTRICAL SHOCK, FIRE OR EXPLOSION

HAZARD

Failure to follow safety warnings could result in

dangerous operation, serious injury, death 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

disconnection. Reconnect wires correctly.

-- Verify proper operation after servicing.

-- Always reinstall access doors after completing service

and maintenance.

!

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal
injury, death, or property damage.

The cabinet MUST have an uninterrupted or unbroken
ground according to current edition of NEC NFPA 70 or
local codes to minimize personal injury if an electrical fault
should occur. In Canada, refer to the current edition of
Canadian Electrical Code CSA C22.1. This may consist of
electrical wire, conduit approved for electrical ground or a
listed, grounded power cord (where permitted by local
code) when installed in accordance with existing electrical
codes. Refer to the power cord manufacturer’s ratings for
proper wire gauge. Do not use gas piping as an electrical
ground.

!

CAUTION

FURNACE MAY NOT OPERATE HAZARD

Failure to follow this caution may result in intermittent
furnace operation.

Furnace control must be grounded for proper operation or
else control will lock out. Control must remain grounded
through green/yellow wire routed to gas valve and manifold
bracket screw.

32

115-- V Wiring

Furnace must have a 115-v power supply properly connected and
grounded.

NOTE: Proper polarity must be maintained for 115-v wiring. If
polarity is incorrect, control LED status indicator light will flash
rapidly and furnace will NOT operate.

Verify that the voltage, frequency, and phase correspond to that
specified on unit rating plate. Also, check to be sure that service
provided by utility is sufficient to handle load imposed by this
equipment. Refer to rating plate or Ta b l e 11 for equipment
electrical specifications.

USA Installations: Make all electrical connections in accordance
with the current edition of the National Electrical Code (NEC)
NFPA 70 and any local codes or ordinances that might apply.

Canada Installations: Make all electrical connections in
accordance with the current edition of the Canadian Electrical
Code CSA C22.1 and any local codes or ordinances that might
apply.

!

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal

injury, death, or property damage.

Do not connect aluminum wire between disconnect

switch and furnace. Use only copper wire. See Fig. 36.

Use a separate, fused branch electrical circuit with a properly sized
fuse or circuit breaker for this furnace. See Ta b le 11 for wire size
and fuse specifications. A readily accessible means of electrical
disconnect must be located within sight of the furnace.

J--Box Installation

!

WARNING

FIRE OR ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal
injury, death, or property damage.

High voltage field connections must be located in J--Box
with furnace, or in field supplied external disconnect
mounted to furnace.

If field --supplied manual disconnect switch is to be mounted
on furnace casing side, select a location where a drill or
fastener cannot damage electrical or gas components.

The J--Box must be used when field line voltage electrical
connections are made to the furnace wiring harness inside the
furnace casing. The J-- Box cover is not required if a field--supplied
external electrical box is attached to the outside of the furnace
casing. The field ground wire and furnace main ground wire are
grounded when the J--Box bracket is attached to the furnace and
the field ground wire and factory ground wire are secured to the
bracket grounding screw. If the J--Box cover is not used, the field
and factory spliced connections must be located inside the external
electrical box. Do not leave splice connections unprotected inside
the furnace.

GROUND

NEUTRAL

LINE VOLTAGE

ELECTRIC

DISCONNECT

SWITCH

COPPER

WIRE ONLY

ALUMINUM

WIRE

A11146

Fig. 36 -- Field--Supplied External Electrical Box on Furnace

Casing

A12226

Fig. 37 -- Installing J--Box (When Used)

33

The J--Box cover, mounting bracket and screws are shipped in the
loose parts bag included with the furnace. See Fig. 37 for J--Box
mounting locations.

The J--Box mounting bracket and green ground screw is used as a
grounding point for all line voltage wiring options. The J--Box
cover may be omitted when electrical connections are made inside
an external electrical box mounted external to the casing.

External Electrical Box on Furnace Casing

NOTE: Check to ensure that external electrical box does not

interfere with duct work, gas piping or the indoor coil drain. See
Fig. 35 for alternate electric entry through top panel.

1. Select and remove 7/8--in. (22 mm) knock--out on the
desired side of the casing. Remove the knock--out from the
casing.

NOTE: If electrical entry through the furnace top panel is used, a
7/8--in. (22 mm) hole must be drilled through the top panel.

2. Drill two (2) 1/8--in. (3 mm) pilot holes through the dimples
in the furnace casing near the 7/8--in. knock--out.

NOTE: If electrical entry through the furnace top panel is used,
mark the screw hole locations using the mounting holes in the
external electrical box as a template.

For a side-- mounted external electrical box, complete the
following:

1. Align the J--Box bracket with the knock--out inside the
furnace casing.

2. Install the threaded end of a strain--relief bushing through
the J--Box bracket and the furnace casing. Strain--relief
bushing should be installed so that the bushing can be
tightened around the wiring harness inside the furnace
casing.

3. Align the external electrical box with the 7/8 --in. (22 mm)
knock--out.

4. Install and tighten the lock--nut on the strain--relief bushing
inside the external electrical box.

5. Fasten the external electrical box to the furnace casing using
two (2) sheet metal screws.

6. Route field power wiring into external electrical box.

7. Pull furnace line voltage power wires through strain--relief
bushing of the external electrical box.

8. Pull the ground wire of the field line voltage wiring through
the strain--relief bushing into the furnace casing.

9. Install the green ground screw to the J--Box bracket and
attach both ground wires to the green ground screw.

10. Connect any code required external disconnect(s) to field
power wiring.

11. Connect field power and neutral leads to furnace power
leads inside the external electrical box as shown in Fig. 32.

For a top panel--mounted external electrical box, complete the
following:

1. Drill two (2) 1/8--in. (3 mm) pilot holes through the dimples
in the furnace casing near the 7/8--in. knock--out on the side
of the casing. Do not remove the knock--out in the side of
the casing.

2. Align the J--Box bracket with the pilot holes inside the
furnace casing.

3. Install 2 screws through the outside of the casing to secure
the J--Box bracket to the furnace casing.

4. Route field power wiring into external electrical box.

5. Pull furnace line voltage power wires through strain--relief
bushing of the external electrical box.

6. Pull the ground wire of the field line voltage wiring through
the strain--relief bushing into the furnace casing.

7. Install the green ground screw to the J--Box bracket and
attach both ground wires to the green ground screw.

8. Connect any code required external disconnect(s) to field
power wiring.

9. Connect field power and neutral leads to furnace power
leads inside the external electrical box as shown in Fig. 34.

Power Cord Installation in Furnace J--Box

NOTE: Power cords must be able to handle the electrical

requirements listed in Tab l e 11. Refer to power cord
manufacturer’s listings.

1. Install J--Box mounting bracket to inside of furnace casing.
See Fig. 37.

2. Route listed power cord through 7/8--in. (22 mm) diameter
hole in casing and J--Box bracket.

3. Secure power cord to J--Box bracket with a strain relief
bushing or a connector approved for the type of cord used.

4. Pull furnace power wires through 1/2--in. (12 mm) diameter
hole in J--Box. If necessary, loosen power wires from
strain—relief wire--tie on furnace wiring harness.

5. Connect field ground wire and factory ground wire to green
ground screw on J--Box mounting bracket as shown in Fig.

37.

6. Connect power cord power and neutral leads to furnace
power leads as shown in Fig. 39.

7. Attach furnace J--Box cover to mounting bracket with
screws supplied in loose parts bag. Do not pinch wires be­tween cover and bracket. See Fig. 37.

BX Cable Installation in Furnace J--Box

1. Install J--Box mounting bracket to inside of furnace casing.
See Fig. 37.

2. Route BX connector through 7/8--in. (22 mm) diameter
hole in casing and J--Box bracket.

3. Secure BX cable to J--Box bracket with connectors ap­proved for the type of cable used.

4. Connect field ground wire and factory ground wire to green
ground screw on J--Box mounting bracket as shown in Fig.

37.

5. Connect field power and neutral leads to furnace power
leads. as shown in Fig. 39.

6. Attach furnace J--Box cover to mounting bracket with
screws supplied in loose parts bag. Do not pinch wires be­tween cover and bracket.

!

WARNING

FIRE, EXPLOSION, ELECTRICAL SHOCK, AND
CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in dangerous
operation, personal injury, death, or property damage.

Do not drill into blower shelf of furnace to route control
wiring. Route any control or accessory wiring to the blower
compartment through external knockouts on the casing.

24--V Wiring

Make field 24 --v connections at the 24-- v terminal strip. See Fig.

40. Connect terminal Y/Y2 as shown in Fig. 39 for proper cooling

operation. Use only AWG No. 18, color--coded, copper thermostat
wire.

NOTE: Use AWG No. 18 color-coded copper thermostat wire for
lengths up to 100 ft. (30 M). For wire lengths over 100 ft., use
AWG No. 16 wire.

The 24--v circuit contains an automotive--type, 3--amp. fuse located
on the control. Any direct shorts during installation, service, or

34

maintenance could cause this fuse to blow. If fuse replacement is
required, use ONLY a 3--amp. fuse of identical size. See Fig. 40.

Thermostats

A single stage heating and cooling thermostat can be used with the
furnace. The furnace control board CPU will control the furnace
and outdoor unit staging. A two stage heating and cooling
thermostat can also be used to control the staging. For two stage
thermostat control of the furnace staging, turn SW1-2 ON at the
furnace control board. For two stage thermostat control of a 2-stage
outdoor unit, remove the ACRDJ jumper from the furnace control
board. Refer to typical thermostat wiring diagrams and the
Sequence of Operation section for additional details. Consult the
thermostat installation instructions for specific information about
configuring the thermostat. See Fig. 40 and 41.

Accessories (See Fig. 38 and 40.)

1. Electronic Air Cleaner (EAC)
Connect an accessory Electronic Air Cleaner (if used) using
1/4--in. female quick connect terminals to the two male
1/4--in. quick--connect terminals on the control board
marked EAC--1 and EAC-- 2. The terminals are rated for
115VAC, 1.0 amps maximum and are energized during
blower motor operation.

2. Humidifier (HUM)

The HUM terminal is a 24 VAC output, energized when the blower
is operating during a call for heat.

Connect an accessory 24 VAC, 0.5 amp. maximum humidifier (if
used) to the ¼--in. male quick--connect HUM terminal and
COM--24V screw terminal on the control board thermostat strip.

NOTE: If the humidifier has its own 24 VAC power supply, an
isolation relay may be required. Connect the 24 VAC coil of the
isolation relay to the HUM and COM/24V screw terminal on the
control board thermostat strip. See Fig. 38.

3. Communication Connector
The furnace can only be controlled by a single or two--stage
thermostat. A Communicating User Interface will not oper­ate this furnace when connected to the Communication
Connector. The Communication Connector on the furnace
control board is only for communication between furnaces
twinned together using a factory accessory twinning kit.
See Fig. 40.

Alternate Power Supplies

This furnace is designed to operate on utility generated power
which has a smooth sinusoidal waveform. If the furnace is to be
operated on a generator or other alternate power supply, the
alternate power supply must produce a smooth sinusoidal
waveform for compatibility with the furnace electronics. The
alternate power supply must generate the same voltage, phase, and
frequency (Hz) as shown in Ta b l e 11 or the furnace rating plate.

Power from an alternate power supply that is non-sinusoidal may
damage the furnace electronics or cause erratic operation.

Contact the alternate power supply manufacturer for specifications
and details.

Table 11 – Electrical Data

V O L T S --­H E R T Z ---

FURNACE SIZE

30040V14 1 1 5 --- 6 0 --- 1 127 104 7.0 9.7 14 38 (11.7) 15

36040V17 1 1 5 --- 6 0 --- 1 127 104 7.2 9.8 14 37 (11.5) 15

36060V14 1 1 5 --- 6 0 --- 1 127 104 7.1 9.7 14 38 (11.7) 15

42060V17 1 1 5 --- 6 0 --- 1 127 104 10.9 14.6 14 25 (7.7) 15

48080V17 1 1 5 --- 6 0 --- 1 127 104 10.0 13.4 14 27 (8.4) 15

60080V21 1 1 5 --- 6 0 --- 1 127 104 14.7/11.2 19.3/14.0

60100V21 1 1 5 --- 6 0 --- 1 127 104 14.8/11.3 19.4/15.0

66120V24 1 1 5 --- 6 0 --- 1 127 104 12.6 16.7 12 34 (10.5) 20

* Permissible limits of the voltage ran ge at which the unit operates satisfactoril y.
# Unit ampacity = 125 percent of largest operating component’s full load amps plus 100 percent of all other potential operating components’ (EAC, humidifier,

etc.) full load amps.

{ Time ---delay type is recommended.
} Length shown is as measured one way along wire path between furnace and service panel for maximum 2 percent voltage drop.

1

Low Amp Kit (KGAPC0101ECM) allows select furnaces to be installed with a 15 Amp Breaker and 14 AWG wire within the listed wire length. Affected data

shown as Default Value/Value with Lower Amp Kit.

PHASE

OPERATING VOLTAGE

RANGE*

Maximum* Minimu m*

To Humidifier Leads

MAXIMUM

UNIT

AMPS

UNIT

AMPACITY#

24 V

Coil

MINIMUM

WIRE SIZE

1

12/14

1

12/14

To HUM Terminal On

Furnace Control Board

AWG

MAXIMUM

WIRE LENGTH

FT (M)}

1

29/241(8.8/7.31) 20/15

1

29/241(8.8/7.31) 20/15

MAXIMUM

FUSE OR
CKT BKR

AMPS{

1

1

To Humidifier Leads

To Com/24V Screw Terminal

on Thermostat Strip

Fig. 38 -- Field--supplied Isolation Relay for Humidifiers with Internal Power Supply

35

A11157

W2

COM

W/W1

Y/Y2

R

G

Fig. 39 -- Typical Two--Stage Field Wiring Diagram

A11401

Fig. 40 -- Example of Variable Speed Furnace Control

36

A190044

THERMOSTAT

THERMOSTAT

D

D

See notes 2, 5, 7, 10, 11, 16, and 17 See notes 1, 2, 4, 6, 7, 9, 10, 11, 15, 16, and 17

Modulating and 2-Stage Furnace with Single-Speed Air Conditioner

THERMOSTAT

D

Modulating and 2-Stage Furnace with Single-Speed Heat Pump

THERMOSTAT

D

See notes 2, 5, 8, 10, 11, 12, 16, and 17

Modulating and 2-Stage Furnace with Two-Speed Air Conditioner

Fig. 41 -- Thermostat Wiring Diagrams

See notes 1, 2, 3, 4, 6, 8, 9, 10, 12, 13, 15, 16, and 17

Modulating and 2-Stage Furnace with Two-Speed Heat Pump

A12222

37

NOTES FOR THERMOSTAT WIRING DIAGRAMS

1. Heat pump MUST have a high pressure switch for HYBRID HEATr dual fuel applications.

2. Refer to outdoor equipment Installation Instructions for additional information and setup procedure.

3. If the heat pump date code is 1501E or earlier, select the “ZONE” position on the two speed heat pump control. Heat pumps with date
code 1601E and later do not have or require a “ZONE” selection.

4. Outdoor Air Temperature Sensor must be attached in all HYBRID HEATr dual fuel applications.

5. Configure the thermostat for air conditioner installations. Refer to thermostat instructions.

6. Configure thermostat for heat pump installations. Refer to thermostat instructions.

7. Configure thermostat for single-stage compressor operation. Refer to thermostat instructions.

8. Configure thermostat for two-stage compressor operation. Refer to thermostat instructions.

9. Configure thermostat for HYBRID HEATr dual fuel operation. Refer to thermostat instructions.

10. NO connection should be made to the furnace HUM terminal when using a thermostat with a 24 volt humidifier output.

11. Optional connection - If wire is connected to W2 on furnace control board, either dip switch SW1-2 or SW1--LHT on furnace control
should be set in ON position to allow thermostat to control furnace staging.

12. Optional connection - If wire is connected to Y2 on furnace control board, ACRDJ jumper on furnace control should be removed to
allow thermostat to control outdoor unit staging.

13. Furnace must control its own staging operation via furnace control algorithm. This is factory default.

14. The RVS Sensing terminal “L” should not be connected. This is used internally to sense defrost operation.

15. If thermostat has internal control of heat pump balance point, DO NOT SELECT the “FURNACE INTERFACE” or “BALANCE
POINT” option on the two-speed heat pump control board. Refer to thermostat instructions

16. Configure Dehumidify function to remove 24 VAC from Dehum terminal on a demand to dehumidify.

17. Thermostat signals may vary. Consult thermostat installation instructions for more information.

VENTING

NOTE: Planning for the venting system should be done in

conjunction with planning for the ductwork, drainage, and furnace
accessories, such as air cleaners and humidifiers. Begin assembling
the venting system AFTER the furnace is set in place in the
required orientation.
Venting for this furnace shall follow all Local codes for Category
IV venting systems. This furnace is CSA approved for venting
with PVC/ABS DWV venting systems. This furnace is also CSA
approved for venting with M&G DuraVentR PolyProR
polypropylene venting systems.
NOTE: THESE INSTRUCTIONS DO NOT CONTAIN
DETAILED INSTALLATION INSTRUCTIONS FOR
POLYPROPYLENE VENTING SYSTEMS. Refer to the
polypropylene venting system manufacturer’s installation
instructions for the polypropylene venting system installation.
NOTE: When using polypropylene venting systems, all venting
materials used, including the vent terminations, must be from the
same manufacturer.

Special Venting Requirements for Installations in
Canada

Installation in Canada must conform to the requirements of CSA
B149 code. Vent systems must be composed of pipe, fittings,
cements, and primers listed to ULC S636. The special vent
fittings, accessory concentric vent termination kits and accessory
external drain trap available from the furnace manufacturer have
been certified to ULC S636 for use with those Royal Pipe and
IPEX PVC vent components which have been certified to this
standard. In Canada, the primer and cement must be of the same
manufacturer as the vent system – GVS-65 Primer (Purple) for
Royal Pipe or IPEX System 636, PVC/CPVC Primer, Purple
Violet for Flue Gas Venting and GVS-65 PVC Solvent Cement for
Royal Pipe or IPEX System 636
Venting, rated Class IIA, 65 deg C. must be used with this venting
system - do not mix primers and cements from one manufacturer
with a vent system from a different manufacturer. Follow the
manufacturer’s instructions in the use of primer and cement and
never use primer or cement beyond its expiration date.
The safe operation, as defined by ULC S636, of the vent system is
based on following these installation instructions, the vent system
manufacturer’s installation instructions, and proper use of primer
and cement. All fire stop and roof flashing used with this system

t, PVC Cement for Flue Gas

(1)

must be UL listed material. Acceptability under Canadian standard
CAN/CSA B149 is dependent upon full compliance with all
installation instructions. Under this standard, it is recommended
that the vent system be checked once a year by qualified service
personnel.
The authority having jurisdiction (gas inspection authority,
municipal building department, fire department, etc.) should be
consulted before installation to determine the need to obtain a
permit.

*IPEX System 636™ is a trademark of IPEX Inc.

Consignes spéciales pour l’installation de
ventilation au Canada

L’installation faite au Canada doit se conformer aux exigences du
code CSA B149. Ce systême de ventillation doit se composer de
tuyaux, raccords, ciments et apprêts conformes au ULC S636. La
tuyauterie de ventilation des gaz, ses accessoires, le terminal
concentrique mural ainsi que l’ensemble du drain de condensation
extérieur fourni par le fabricant de cette fournaise ont été certifiés
ULCS 636 pour l’application des composantes Royal Pipe, IPEX
PVC qui sont certifiées à ce standard. Au Canada, l’apprêt et le
ciment doivent être du même fabricant que le système
d’évacuation. L’apprêt GVS-65 (Purple) et le ciment-solvant
GVS-65 doivent être utilisé avec les Royal Pipe. Système IPEX
636, apprêt PVC/CPVC, Purple pour évacuation des gaz de
combustion et système IPEX 636(1)t, ciment PVC pour
évacuation des gaz de combustion, coté classe IIA, 65 deg C.
doivent être utilisés avec le système d’évacuation IPEX 636 – Ne
pas combiner l ’apprêt et le ciment d’un manufacturier avec un
système d’évacuation d’un manufacturier différent.
Bien suivre les indications du manufacturier lors de
l’apprêt et du ciment et ne pas utiliser ceux-ci si la date

d expiration est atteinte.

L’opération sécuritaire, tel que définit par ULC S636, du système
de ventilation est basé sur les instructions d’installation suivantes,
ainsi que l’usage approprié de
solin de toit utilisés avec ce système doivent être des matériaux
listés UL. L’acceptation du standard Canadien CAN/CSA B149
est directement relié à l’installation conforme aux instructions ci­haut mentionnées. Le standard Canadien recommande l’inspection
par un personel qualifié et ce, une fois par année.
Les autoritées ayant juridiction (inspecteurs de gas, inspecteurs en
bâtiments, département des incendies, etc) devraient être consultées
avant l’installation afin de déterminer si un permis est requis.

l apprêt et ciment. Tout arrët feu et

l utilisation de

38

!

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 for each appliance
connected to the venting system being placed into operation,
while all other appliances connected to the venting system are
not in operation:

1. Seal any unused openings in venting system.

2. Inspect the venting system for proper size and

horizontal pitch, as required in the National Fuel Gas
Code, ANSI Z223.1/NFPA 54 or the CSA B149 Nat­ural Gas and Propane Installation Code 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 Code.

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.

General

If this furnace replaces a furnace that was connected to a vent
system or chimney, the vent or vent connectors of other remaining
appliances may need to be re--sized. Vent systems or vent
connectors of other appliances must be sized to the minimum size
as determined using appropriate table found in the current edition
of National Fuel Gas Code NFPA 54/ANSI Z-- 223.1. In Canada,
refer to CAN/CSA--B149.1.

An abandoned masonry chimney may be used as a raceway for
properly insulated and supported combustion--air (when
applicable) and vent pipes. Each furnace must have its own set of
combustion--air and vent pipes and be terminated individually, as
shown in Fig. 56 for Direct Vent (2--Pipe) system, or Fig. 57 for
single--pipe or ventilated combustion air option.

A furnace shall not be connected to a chimney flue serving a
separate appliance designed to burn solid fuel.

Other gas appliances with their own venting system may also use
the abandoned chimney as a raceway providing it is permitted by
local code, the current edition of the National Fuel Gas Code, and
the vent or liner manufacturer’s installation instructions. Care must
be taken to prevent the exhaust gases from one appliance from
contaminating the combustion air of other gas appliances.

Do not take combustion air from inside the chimney when using
ventilated combustion air or single--pipe vent option.

These furnaces can be vented as direct-- vent (two--pipe), ventilated
combustion air or non-direct (single--pipe) vent system. Each type
of venting system is described below. Common venting between
these furnaces or other appliances is prohibited.

Materials

USA

Combustion air and vent pipe, fittings, primers, and solvents must
conform to American National Standards Institute (ANSI)
standards and American Society for Testing and Materials (ASTM)
standards. See Table 12 for approved materials for use in the USA.
This furnace is also CSA approved for venting with M&G
DuraVentR PolyProR polypropylene venting systems.

Canada

Special Venting Requirements for Installations in Canada,
Installation in Canada must conform to the requirements of
CAN/CSA B149 code. Vent systems must be composed of pipe,
fittings, cements, and primers listed to ULC S636. M&G DuraVent
PolyPro polypropylene venting systems are ULC S636 listed.

NOTE: When using polypropylene venting systems, all venting
materials used, including the vent terminations must be from the
same manufacturer.

39

Table 12 – Approved Combustion-Air and Vent Pipe, Fitting and Cement Materials (USA Installations)

MATERIALS

1. All pipe, fittings, primers*, and solvents* must conform to American National Standards Institute (ANSI) standards and
American Society for Testing and Materials (ASTM) standards or ULC S636 where required by code.

USA

CANADA

Material Description

PVC

ABS

CPVC

*PVC and ABS pipe may use either DWV or pressure rated fittings.
**Colored or tinted solvents or primers must be used where required by code in the USA
†ABS plastic does not require a primer before solvent cementing. A cleaner for ABS is recommended to remove any surface residue. ABS

cleaners are not subject to ASTM standards.

Polypropylene Approved Manufacturer Solvents Primers Cements

Poly Pro® M & G Dura Vent Not Permitted

NOTE: Polypropylene vent systems are UL− 1738 and ULC S636 listed and assembled using mechanical fastening systems supplied by the
vent manufacturer.

2. See Table below for approved materials for use in the U.S.A.

3. ULC S636 vent systems must be composed of pipe, fittings, cements, and primers from the same supplier.

4. Factory accessory concentric vent kits are ULC S636 listed.

1. Installation in Canada must conform to the requirements of CAN/CSA B149 code.

2. Vent systems must be composed of pipe, fittings, cements, and primers from the same supplier and listed to ULC S636.

3. Not all materials below may be approved or listed to ULC S636.

4. Royal Pipe and IPEX are approved suppliers of ULC S636 pipe, fittings, cements and primers*.

5. Factory accessory concentric vent kits are ULC S636 listed for use with Royal Pipe and IPEX venting systems

Typ e ASTM or ULC Specification

Pipe Solvents/Primers** Cements

Pressure Pipe Schedule 40 D1785

DWV Schedule 40 D1785/D2665

Cellular Core Schedule 40 F891

SDR 26 N/A D2241
SDR 21 N/A D2241

IPEX Schedule 40 ULC S636 ULC S636 ULC S636 ULC S636

Royal Pipe Schedule 40 ULC S636 ULC S636 ULC S636 ULC S636

ABS Schedule 40 D1527 D2468

DWV-- IPS Sizes Schedule 40 D2661 D2661

Cellular Core DWV-- IPS Sizes Schedule 40 F628

Pressure Pipe Schedule 40 F441 F438 F656 F493

SDR N/A F442 N/A

IPEX Schedule 40 ULC S636 ULC S636 ULC S636 ULC S636

Royal Pipe Schedule 40 ULC S636 ULC S636 ULC S636 ULC S636

D2466

or

D2665

F656 D2564

Clear Cleaner For ABS†

D2235

Vent i ng Systems

!

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow the instructions outlined below for each
appliance being placed into operation could result in carbon
monoxide poisoning or death.

For all venting configurations for this appliance and other gas
appliances placed into operation for this structure, provisions
for adequate combustion, ventilation, and dilution air must be
provided in accordance with:
USA Installations: Section 9.3 current edition of NFPA
54/ANSI Z223.1, Air for Combustion and Ventilation and
applicable provisions of the local building codes.

Canadian Installations: Part 8 of current edition of
CAN/CSA--B149.1. Venting Systems and Air Supply for
Appliances and all authorities having jurisdiction.

NOTICE

RECOMMENDED SUPPORT FOR
VENT TERMINATION

It is recommended that sidewall vent terminations of over 24
inches (0.6 M) in length or rooftop vent terminations of over
36 inches (1 M) in length be supported by EITHER the
factory accessory vent termination kit or field--supplied
brackets or supports attached to the structure. A factory
accessory vent termination kit may be used for direct vent
terminations. Termination kits are available for 2 --in. or 3--in.
pipe. See Table 13 for available options.

40

Table 13 – Vent Termination Kit for Direct Vent (2--pipe) Systems

p

Vent and

Combustion Air

Pi

eDiameters

1 1/2--in. (38 mm) No Yes No No No 2--in. (51 mm)
2--in. (51 mm) No Yes No No No 2--in. (51 mm)

2 1/2--in. (64 mm) No No No Yes No

3--in. (76--mm) No No No Yes No 3--in. (76 mm)
4--in. (102 mm) No No No Yes Ye s 3--in. (76 mm)

11/2--in.
(38 mm)

Approved Two- Pipe Termination Fittings

2--in.

(51 mm)

21/2--in.

(64 mm)

3--in.

(76--mm)

4--in.

(102 mm)

Allowable

Concentric Vent

Kit

2--in. (51 mm)
3--in. (76 mm)

Direct Vent / 2-Pipe System

In a direct-vent (2-pipe) system, all air for combustion is taken
directly from outdoor atmosphere, and all flue products are
discharged to outdoor atmosphere. Combustion-air and vent pipes
must terminate together in the same atmospheric pressure zone,
either through the roof (preferred) or a sidewall. See Fig. 54 for
references to clearances required by National code authorities.

NOTICE

OPTIONAL CONFIGURATION FOR COMBUSTION
AIR INLET PIPE

In applications where there is a risk of excessive moisture
entering the combustion air inlet pipe, a moisture trap may be
added to the inlet pipe to help prevent moisture from entering
the furnace from the combustion air inlet pipe. See Fig. 43.

When sizing venting systems, the equivalent length of the
optional inlet pipe moisture trap must be taken into account.

OPTIONAL VENTING BELOW THE FURNACE

The venting system may be positioned below the furnace
ONLY IF the factory accessory External Vent Trap Kit is used.
The External Vent Trap Kit is only approved for PVC/ABS
DWV venting systems.

CAREFULLY FOLLOW THE INSTRUCTIONS
PROVIDED WITH THE EXTERNAL VENT TRAP KIT
FOR LAYING OUT THE VENTING SYSTEM AND
THE DRAIN SYSTEM. The instructions included with this

furnace DO NOT APPLY to vent systems that are located
below the furnace.

NOTICE

!

WARNING

Ventilated Combustion Air Systems

In a ventilated combustion air option, the vent terminates and
discharges the flue products directly to the outdoors similar to a
direct vent system. See Fig. 55 for references to clearances required
by National code authorities.

All air for combustion is piped directly to the furnace from a space
that is well ventilated with outdoor air (such as an attic or crawl
space) and the space is well isolated from the living space or
garage. Combustion air requirements for this option are the same as
the requirements for providing outside air for combustion for a
single pipe vent system. Refer to the “Air For Combustion and
Ventilation” Section.

Non-Direct Vent (1-pipe) System

In a non direct-vent (1-pipe) system, all air for combustion is taken
from the area adjacent to furnace, and all flue products are
discharged to outdoor atmosphere. Air for combustion must be
supplied as described in the Air For Combustion and Ventilation
Section. Do not use an abandoned chimney to supply outside air to
the furnace. See Fig. 55 for references to vent clearances required
by National code authorities.

A combustion air pipe to the outdoors is not required for a
single-- pipe vent system. A 12-in. (304 mm) long pipe with a 2-- in.
(51 mm) tight radius 90 degree elbow is required to be attached to
the combustion air pipe adapter on the furnace. See Fig. 58. This
short inlet air pipe helps to ensure stable combustion, as well as
allow for sound attenuation. To aid sound attenuation, point the
inlet air pipe away from occupants. An extra elbow and/or five
feet of pipe may be used to accomplish the sound attenuation
function.

CARBON MONOXIDE POISONING HAZARD

Failure to follow the instructions outlined below for each
appliance being placed into operation could result in carbon
monoxide poisoning or death.

The instructions included with this furnace DO NOT APPLY
to vent systems that are located below the furnace.

CAREFULLY FOLLOW THE INSTRUCTIONS
PROVIDED WITH THE EXTERNAL VENT TRAP KIT
FOR LAYING OUT THE VENTING SYSTEM AND
THE DRAIN SYSTEM when all or part of the venting

system is placed below the furnace.

Proper configuration of the venting and drain system is critical
when placing all or part of the venting system below the level
of the furnace. VENT GASSES COULD BE RELEASED
FROM THE DRAINAGE SYSTEM if the instructions
provided with the External Vent Trap Kit are not followed.

Locating the Vent Termination

General

NOTE: Termination Requirements for the Provinces of
Alberta and Saskatchewan are located at the end of this
section.

Combustion--air inlet pipe (direct vent/2--pipe system only) and
vent pipe must terminate outside structure, either through sidewall
or roof.

For vent termination clearance, references to National codes are
shown in Fig. 54 for Direct Vent/2-- Pipe system and Fig. 55 for
Ventilated Combustion Air/Non--direct Vent/1--Pipe system. For
exterior termination arrangements, refer to Fig. 56 for Direct
Vent/2 --Pipe system and Fig. 57 for V entilated Combustion
Air/Non--Direct/1--Pipe system. Contact Local code authorities for
other requirements to and/or exemptions from the National codes
shown in the figures.

Roof termination is the recommended termination location. Roof
terminations provide better performance against sustained

41

prevailing winds. The roof location is preferred since the vent and
combustion air system is less susceptible to damage or
contamination. The termination is usually located away from
adjacent structures or other obstacles such as inside corners,
windows, doors or other appliances. It is less prone to icing
conditions, and it often has less visible vent vapors.

Sidewall terminations may require sealing or shielding of building
surfaces with a corrosive resistance material due to the corrosive
properties of combustion products from the vent system, as well as
protection of adjacent structures.

NOTICE

RECOMMENDED SUPPORT FOR
VENT TERMINATIONS

It is recommended that sidewall vent terminations in excess of
24 inches (.6 M) or rooftop terminations in excess of 36 inches
(1 M) in vertical length be supported by EITHER the Direct
Vent Termination Kit shown in Table 13 or by field --supplied
brackets or supports fastened to the structure.

When determining appropriate location for termination, consider
the following guidelines:

1. Comply with all clearance requirements stated in Fig. 54 or
Fig. 55 per application.

2. Termination or termination kit should be positioned where
vent vapors will not damage plants/shrubs, air conditioning
equipment or utility meters.

3. Do not locate termination directly into prevailing winds.
Termination should be positioned so that it will not be
affected by sustained prevailing winds over 30 mph, wind
eddy, such as inside building corners, or by recirculation of
flue gases, airborne leaves, or light snow.

4. Termination or termination kit should be positioned where it
will not be damaged by or subjected to foreign objects such
as stones, balls, etc.

5. Termination or termination kit should be positioned where
vent vapors are not objectionable.

Direct Vent / 2-Pipe System

Direct vent (2--pipe) vent and combustion air pipes must terminate
outside the structure. See Fig. 54 for references to vent clearances
required by National code authorities. Allowable vent and
combustion air terminations are shown in Fig. 56.

!

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow the instructions outlined below for each
appliance being placed into operation could result in carbon
monoxide poisoning or death.

For all venting configurations for this appliance and other gas
appliances placed into operation for the structure, provisions
for adequate combustion, ventilation, and dilution air must be
provided in accordance with:
USA Installations: Section 9.3 current edition of NFPA
54/ANSI Z223.1 Air for Combustion and Ventilation and
applicable provisions of the local building codes.

Canadian Installations: Part 8 of current edition of
CAN/CSA--B149.1. Venting Systems and Air Supply for
Appliances and all authorities having jurisdiction.

Ventilated Combustion Air

The vent pipe for a Ventilated Combustion Air System must
terminate outdoors. See Fig. 55 for references to vent clearances
required by National code authorities. Allowable vent terminations
are shown in Fig. 57. The combustion air pipe terminates in a
well--ventilated attic or crawl space. Follow the clearances as
shown in Fig. 59.

The combustion air pipe cannot terminate in attics or crawl spaces
that use ventilation fans designed to operate in the heating season.
If ventilation fans are present in these areas, the combustion air
pipe must terminate outdoors as a Direct Vent System.

Non-Direct Vent / 1-Pipe System

The vent pipe for a Non Direct Vent (1--pipe) system must
terminate outdoors. See Fig. 55 for references to vent clearances
required by National Code authorities. Allowable vent
terminations are shown in Fig. 57.

A combustion air inlet pipe to the outdoors is not required for a
Non--Direct (single--pipe) Vent System. A 12--in. long section of
pipe with a tight radius 2--in. (51 mm) 90 degree elbow is required
to be attached to the furnace. See Fig. 58. This short inlet air pipe
helps to ensure stable combustion, as well as allow for sound
attenuation. To aid sound attenuation, point the inlet air pipe away
from occupants. An extra elbow and/or five feet of pipe may be
used to accomplish the sound attenuation function.

Termination Requirements for the Provinces of Alberta and
Saskatchewan

The Provinces of Alberta and Saskatchewan require a minimum
unobstructed distance of 4 ft. (1.2 M) from the foundation to the
property line of the adjacent lot for vent termination of any
appliance with an input over 35,000 btuh. If there is less than 4 ft.
(1.2 M) of unobstructed distance to the property line of the
adjacent lot, no type of vent termination is permitted for appliances
with inputs greater than 35,000 btuh.

There are no additional restrictions on unobstructed distances
greater than 8 ft. (2.4 M). All single, two-pipe and concentric vents
may be used, providing all other Code and manufacturer’s
requirements in these instructions are adhered to. Refer to the
appropriate Vent Termination section above for locating the vent
termination

If the unobstructed distance from the foundation to the property
line of the adjacent lot is no less than 4 ft. (1.2 M) and no greater
than 8 ft. (2.4 M), it will be necessary to re-direct the flue gas
plume. In this situation, a concentric vent kit cannot be used. A
2-pipe termination (or single pipe termination when permitted) that
re-directs the flue gas away by use of an elbow or tee, certified to
ULC S636 from the adjacent property line must be used. See Fig.

58.
The concentric vent kit currently cannot be modified to attach an

elbow to the vent portion of the rain cap. A tee attached to the rain
cap could potentially direct the flue gas plume toward the intake air
stream and contaminate the incoming combustion air for the
furnace.

Refer to Fig. 58 for terminations approved for use in Alberta and
Saskatchewan.

Size the Vent and Combustion Air Pipes

General

Furnace combustion air and vent pipe connections are sized for
2-in. (50 mm ND) PVC/ABS DWV pipe. The combustion air and
vent pipe connections also accommodate 60 mm polypropylene
venting systems with outside diameters of approximately 60 mm
(2--3/8 inches). Any pipe diameter change should be made outside
furnace casing in vertical pipe. Any change in diameter to the pipe
must be made as close to the furnace as reasonably possible. See
Fig. 42.

The Maximum Vent Length for the vent and combustion air pipe
(when used) is determined from the Maximum Equivalent Vent

42

Length in Table 16 minus the number of fittings multiplied by the
deduction for each type of fitting used from Table 17.

NOTICE

OPTIONAL CONFIGURATION FOR COMBUSTION
AIR INLET PIPE

In applications where there is a risk of excessive moisture
entering the combustion air inlet pipe, a moisture trap may be
added to the inlet pipe to help prevent moisture from entering
the furnace from the combustion air inlet pipe. See Fig. 43.

When sizing venting systems, the equivalent length of the
optional moisture trap (15 feet/5 M) must be taken into
account.

A

A

FURNACE

NOT IN
HORIZONTAL
SECTION

PIPE DIAMETER

TRANSITION IN

VERTICAL SECTION

A93034

Fig. 42 -- Combustion Air and Vent Pipe Diameter Transition

Location and Elbow Configuration

A

TO CODE --APPROVED DRAIN OR CONDENSATE PUMP

Recommend “T” fitting with 4-- inch minimum height standpipe (A) of same diameter or larger extending upward.

Tee

Dry Well

Representative drawing only, some models may vary in appearance.

Dry Well

Cap

(water tight

Cap

and removable)

(water tight

and removable)

Representative drawing only, some models may vary in appearance.

Fig. 43 -- Recommended Combustion Air Inlet Moisture Trap

Recommended Combustion Air Inlet Moisture T rap

Recommended to prevent moisture from trickling into the furnace
vestibule, a trap can be installed in the intake air pipe near the
furnace. To prevent moisture, connecting a drain line to the trap is
recommended as trace amounts of moisture will evaporate into the

Tee

Tee

Dry Well

Cap

(water tight

and removable)

A170122A

intake air stream. If the combustion air inlet is located near a
moisture exhaust duct, or there are other concerns of excessive
moisture being drawn into the combustion air inlet, it is
encouraged to connect a drain line to the trap.

43

The trap can be constructed from a running tee of the same
diameter of the intake air pipe with EITHER a removable cap
attached to a 6-inch long pipe connected to the tee or the External
Vent Trap Kit to help prevent contaminants from entering the
furnace. See Fig. 43.

The External Vent Trap Kit accessory may be used as a trap for the
combustion air inlet pipe if a large amount of moisture must be
removed. The drain line may be connected to the same drain as the
furnace condensate and the evaporator coil condensate line ONLY
if the inlet air trap drain and the evaporator coil drain empty into an
open segment of pipe above the drain. See Fig.18. When using
the External Vent Trap Kit, refer to those instructions for proper
drain connections.

The tee may also be connected to the intake air pipe on the side of
the casing. See Fig. 43.

In any configuration, it will be necessary to add the equivalent
length of the tee (15 feet/5 M) to the Total Equivalent Vent Length
of the venting system.

NOTICE

ADDITIONAL INFORMATION FOR
POLYPROPYLENE VENTING SYSTEMS

Polypropylene venting systems include flexible vent pipe.
These flexible vent pipes have a different equivalent vent
length than straight sections of PVC/ABS DWV vent pipe. Be
sure to make the appropriate deductions from the Maximum
Equivalent Vent Length (MEVL), or additions to the Total
Equivalent Vent Length (TEVL), when applying flexible vent
pipes in polypropylene venting systems. See the
polypropylene vent system manufacturer’s installation
instructions for details.

When using metric-sized venting systems, use these
equivalencies for obtaining the proper MEVL from the Tables:
Use 2” Vent Tables for 60 mm (o.d.) vent systems
Use 3” Vent Tables for 80 mm (o.d.) vent systems
Use 4” Vent Tables for 100 mm (o.d.) vent systems

The measured length of pipe used in a single or 2--pipe termination
is included in the total vent length. Include deductions from the
Maximum Equivalent Vent Length (MEVL) contained in the
Venting Tables for elbows and flexible vent pipe. Factory
accessory concentric vent terminations or pipe lengths and elbows
used for “standard” vent terminations (see vent termination figures
associated with Table 16) do not require a deduction from the
Maximum Equivalent Vent Length. Include a deduction for a Tee
when used for Alberta and Saskatchewan terminations.
NOTE: Polypropylene venting systems MAY require additional
deductions from the MEVL, or additions to the TEVL, for vent
terminations and flexible pipe sections. See the polypropylene
venting system manufacturer’s instructions for details on
equivalent lengths of vent terminations and flexible vent pipes,
and for calculating total vent lengths.
To calculate the Total Equivalent Vent Length (TEVL) of the
venting system:

1. Measure the individual distance from the furnace to the ter­mination for each pipe.

2. Count the number of elbows for each pipe.

3. For each pipe, multiply the number of elbows by the equiv­alent length for the type of elbow used. Record the equiva­lent length of all the elbows for each pipe.

4. If a Tee is used on the termination (Alberta and
Saskatchewan, when required) record the equivalent length
of the Tee used.

5. Calculate Total Equivalent Vent Length by adding the
equivalent lengths of the fittings to the lengths of the indi­vidual vent and combustion air pipes.

6. When using polypropylene venting systems with flexible
vent pipes, perform adjustments for the equivalent length of
the flexible vent pipe to the calculated total equivalent

venting system length. See the polypropylene vent system
manufacturer’s instructions for details.

7. Select a diameter of vent pipe from Table 16 and note the
Maximum Equivalent Vent Length (MEVL) shown for that
application for that specific furnace input size. Compare the
Total Equivalent Vent Length (TEVL) to the MEVL:

8. If the Total Equivalent Vent Length is shorter than the
Maximum Equivalent Vent Length for the diameter of pipe
chosen, then that diameter of pipe selected may be used.

9. If the Total Vent Length is longer than the Maximum
Equivalent Vent Length for the diameter of pipe chosen,
that diameter pipe MAY NOT be used for venting the fur­nace. Try the next larger diameter pipe

NOTE: If the calculated Total Equivalent Vent Lengths results in
different diameter pipes for the vent and combustion air, select the
larger diameter for both pipes.
NOTE: If the Maximum Vent Length for diameter of the pipe
selected is longer than the measured length and the equivalent
length of all the fittings and terminations (TEVL), recalculate
Total Equivalent Vent Length using the next smaller diameter. If
the Maximum Equivalent Vent Length is still longer than the
longer TEVL of the vent pipe or combustion air pipe, then that
diameter of pipe selected may be used.
When installing vent systems pipe lengths of 10 ft. (3 M) or less,
use the smallest allowable pipe diameter. Using a pipe size greater
than required for short venting systems may result in loss of
efficiency, incomplete combustion, flame disturbance, or flame
sense lockout.
For vent systems longer than 10 ft. (3 M), any larger diameter vent
pipe shown in Table 16 FOR THAT SIZE FURNACE may be
used.

.

Combustion Air and Vent Piping Insulation
Guidelines

NOTE: Use closed cell, neoprene insulation or equivalent.

The vent pipe may pass through unconditioned areas. The amount
of exposed pipe allowed is shown in Table 15.

1. Using winter design temperature (used in load calculations),
find appropriate temperature for your application and fur­nace model.

2. Determine the amount of total and exposed vent pipe.

3. Determine required insulation thickness for exposed pipe
length(s).

4. When combustion air inlet piping is installed above a sus­pended ceiling, the pipe MUST be insulated with moisture
resistant insulation such as Armaflex or other equivalent
type of insulation.

5. Insulate combustion air inlet piping when run in warm, hu­mid spaces.

6. Install the insulation per the insulation manufacturer’s in­stallation instructions.

NOTE: Pipe length (ft. / M) specified for maximum pipe lengths
located in unconditioned spaces cannot exceed total allowable pipe
length as calculated from Table 16.

Configure the Furnace

!

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal
injury or death.

To route the vent pipe and combustion air pipe through the
furnace, the manufacturer supplied kit must be used. Failure
to properly seal the blower compartment from the furnace
vestibule could result in the circulation of carbon monoxide
throughout the structure. The vent pipe and combustion air
pipe must be a continuous pipe while passing through the
blower compartment. Seals supplied in this kit must be
installed per the instructions provided. Follow all
procedures outlined in these instructions.

44

Near Furnace Vent Connections

Offsets in the vertical portion of the vent pipe should be made with
45 deg. elbows instead of 90 deg. elbows. Short horizontal runs of
vent pipe are difficult to pitch correctly and may trap water in the
vent pipe.

Trapped water in the vent pipe may result in nuisance pressure
switch tripping.

Install the Vent and Combustion Air Pipes

With the furnace installed in the required position, remove the
desired knockouts from the casing. It will be necessary to remove
one knockout for the vent pipe and the other knockout for the
combustion air connection. See Fig. 13.
Use a flat blade screwdriver and tap on the knockout on opposite
sides, where the knockout meets the casing. Fold the knockout
down with duct pliers and work the knockout back and forth until
it is removed. Trim any excess metal from the knockout with tin
snips.
The vent elbow can be rotated to the required location on the
casing if necessary. See Fig. 50. To rotate the vent elbow:

1. Loosen the clamp on the inlet of the vent elbow attached to
the inducer.

2. Rotate the vent elbow to the required position. There are
rounded notches on the vent elbow to align it with the
inducer housing for each orientation.

3. Tighten the clamp around the vent elbow. Torque the clamp
to 15 lb-- in. See Fig. 45--48.

Installing the Vent Pipe Adapter and Combustion Air
Pipe Adapter

!

WARNING

NOTE: The vent pipe adapter can be distinguished from the inlet

pipe adapter by the absence of an internal pipe--stopping ring. The
vent pipe can pass through the vent pipe adapter; it cannot pass
through the inlet pipe adapter.

2. Align the screw holes in the plastic vent pipe adapter with
the dimples in the casing.

3. Pilot drill the screw holes for the adapter in the casing and
attach the vent pipe adapter to the furnace with sheet metal
screws

12" (256mm) minimum
to
60”(1524 mm) or
1 additional elbow maximum

CASING SIDE OR TOP ATTACHMENT

(NON-DIRECT VENT FOR ALL MODELS EXCEPT MODULATING UNLESS

COMBUSTION AIR PIPE

INSTALLED IN ATTIC OR CRAWL SPACE)

A13406

Fig. 44 -- Combustion Air Pipe Attachment

7

6

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury or
death.

To route the vent pipe and combustion air pipe through the
furnace, the manufacturer supplied kit must be used. Failure to
properly seal the blower compartment from the furnace
vestibule could result in the circulation of carbon monoxide
throughout the structure. The vent pipe and combustion air pipe
must be a continuous pipe while passing through the blower
compartment. Seals supplied in this kit must be installed per the
instructions provided. Follow all procedures outlined in these
instructions.

!

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury
or death.

DO NOT use cement to join polypropylene venting systems.
Follow the polypropylene venting system manufacturer’s
instructions for installing polypropylene venting systems.

NOTE: The rubber coupling that attaches to the vent pipe adapter
must be used. The adapter seals the vent pipe to the casing and
reduces the strain on the vent elbow attached to the inducer.

1. Apply the gaskets to the vent pipe and combustion air pipe
adapters. If supplied, remove and discard round center
“slug” from interior of gasket. See Fig. 49.

Any other unused
knockout may be used
for combustion air
connection.

Rotate vent elbow to

4

5

1

3

2

&

5

required position.

UPFLOW LEFT CONFIGURATION

A11309A

45

A

A

Rotate vent elbow to

A

required position.

7

6

4

5

5

2

1

3

5

2

ny other unused
knockout may be used
for combustion air
connection.

Rotate vent elbow to
required position.

4

5

1

UPFLOW RIGHT CONFIGURATION

7

ny other unused
knockout may be used
for combustion air
connection.

6

UPFLOW VERTICAL VENT

Fig. 45 -- Upflow Configuration (Appearance May Vary)

See “Notes for Venting Options”

3

A11308A

3

2

4

5

A11310A

ny other unused
knockout may be used
for combustion air
connection.

6

7

DOWNFLOW RIGHT CONFIGURATION

A11312A

5

1

Requires Accessory Internal Vent Kit.

See Product Data for current kit number.

DOWNFLOW VERTICAL

A11313A

Fig. 46 -- Downflow Configurations (Appearance May Vary)

See “Notes for Venting Options”

3

7

DOWNFLOW LEFT CONFIGURATION

Rotate vent elbow to
required position.

2

5

1

6

4

5

HORIZONTAL LEFT ---VERTICAL VENT CONFIGURATION

A11311A

A11327A

46

Alternate combustion air
connection.

4

4

Rotate vent
elbow to
required
position.

Vent Pipe

5

6

HORIZONAL LEF T ---LEFT VENT CONFIGURATION

Requires Accessory Vent Kit

See Product Data for

Current Kit Number

HORIZONTAL LEFT ---RIGHT VENT CONFIGURATION

Fig. 47 -- Horizontal Left (Appearance May Vary)

See “Notes for Venting Options”

A11328A

A11329A

Requires Internal Vent Kit

See Product Data for Current Kit Number

HORIZONTAL RIGHT --- LEFT VENT CONFIGURATION

A11336

ALTERNATE
COMBUSTION
AIR CONNECTIONS

HORIZONTAL RIGHT --- RIGHT VENT CONFIGURATION

A11335

Fig. 48 -- Horizontal Right (Appearance May Vary)

See “Notes for Venting Options”

ALTERNATE
COMBUSTION
AIR CONNECTIONS

HORIZONTAL RIGHT ---VERTICAL VENT CONFIGURATION

A11337

47

NOTES FOR VENTING OPTIONS

1. Attach vent pipe adapter with gasket to furnace casing.

2. Align notches in rubber coupling over standoffs on adapter. Slide clamps over the coupling.

3. Slide vent pipe through adapter and coupling into vent elbow.

4. Insert vent pipe into vent elbow.

5. Torque all clamps 15 lb.--in.

6. Attach combustion air pipe adapter with gasket to furnace.

7. Attach combustion air pipe to adapter with silicone. Pilot drill a1/8--in. hole in adapter and secure with a #7 x 1/2--in. sheet metal

screw.

Attach gaskets to vent pipe and
combustion air adapters.

Fig. 49 -- Vent Coupling and Adapter with Gaskets

Vent Coupling and Adapter

A13074

TABS ON THE INDUCER OUTLET RESTRICTOR SNAP

INTO THE SLOTS AT THE OUTLET OF THE INDUCER

SEE MAXIMUM EQUIVALENT VENT LENGTH TABLE

(10FT. (3.1 M) OF VENT OR LESS ONLY)

Fig. 50 -- Inducer Vent Elbow

FOR USAGE:

48

A170006

Slope vent pipe back to the
furnace at least ¼” per foot

Avoid short horizontal osets with 90
deg. Elbows. Short osets can be
dicult to slope and may trap con­densate.

Use 45 deg. Elbows where
possible, to ensure conden­sate drainage.

Fig. 51 -- Near Furnace Vent Connections

Table 14 – Hanger Spacing

Diameter

11/2--in. 3--ft. 2 1/2--ft. 3--ft. 3--ft. 3.25--ft.

38--mm 914--mm 762-- mm 914-- mm 914-- mm 1000 mm

2--in. 3--ft. 3--ft. 3--ft. 3--ft. 3.25--ft.

51--mm 914--mm 914-- mm 914-- mm 914-- mm 1000 mm

21/2--in. 3 1/2--ft. 3--ft. 3 1/2--ft. 3 1/2--ft. 3.25--ft.

64--mm 1067--mm 914--mm 1067--mm 1067--mm 1000 mm

3--in. 3 1/2--ft. 3--ft. 3 1/2--ft. 3 1/2--ft. 3.25--ft.

76--mm 1067--mm 914--mm 1067--mm 1067--mm 1000 mm

4--in. 4--ft. 3 1/2--ft. 4--ft. 4--ft. 3.25--ft.

PVC Sch 40 SDR 21 & 26 ABS CPVC Polypropylene

8. Slide the end of the rubber vent coupling with notches in it
over the standoffs on the vent pipe adapter.

9. Insert a length of vent pipe through the coupling into the
outlet of the vent elbow.

10. Tighten the clamp around the outlet of the vent elbow.
Torque the clamp to 15 lb--in.

Material

9. Torque clamp on vent coupling 15 lb-- in.

10. Insert the combustion air pipe into the adapter.

11. Pilot drill a screw hole through the adapter into the combus­tion air pipe and secure the pipe to the adapter with sheet
metal screws. DO NOT DRILL INTO POLYPROPY-
LENE VENT PIPES. Use an optional accessory vent cou­pling, if needed.

NOTICE

12. Seal around the combustion air pipe with silicone or foil
tape. SILICONE SEALERS MAY NOT BE APPRO-

The following instructions are for PVC/ABS DWV vent
piping only. DO NOT USE THESE TECHNIQUES FOR
POLYPROPYLENE VENT PIPING SYSTEMS. See the
polypropylene vent system manufacturer’s instructions for
installing polypropylene venting systems.

PRIATE FOR P OLYPROPYLENE VENT SYSTEMS.
SEE POLYPROPYLENE VENT SYSTEM MANU­FACTURER’S INSTRUCTIONS.

13. After pipes have been cut and pre--assembled, apply gener­ous layer of cement primer to pipe fitting socket and end of
pipe to insertion mark. Quickly apply approved cement to

Install the remaining vent and combustion air pipes as shown
below. It is recommended that all pipes be cut, prepared, and
pre-- assembled before permanently cementing any joint.

1. Working from furnace to outside, cut pipe to required
length(s).

2. De--burr inside and outside of pipe.

3. Chamfer outside edge of pipe for better distribution of
primer and cement.

4. Complete the vent and combustion air pipe installation by
connecting the concentric vent or by installing the required
termination elbows as shown in Figs. 56, 57 and 58.
For Ventilated Combustion Air Termination, see Fig. 59.

5. Clean and dry all surfaces to be joined.

6. Check dry fit of pipe and mark insertion depth on pipe.

7. Insert the vent pipe into the vent elbow.

8. Torque clamp on vent elbow 15 lb--in.

end of pipe and fitting socket (over primer). Apply cement
in a light, uniform coat on inside of socket to prevent
buildup of excess cement. Apply second coat. DO NOT

CEMENT POLYPROPYLENE FITTINGS.

14. While cement is still wet, twist pipe into socket with 1/4--in.
turn. Be sure pipe is fully inserted into fitting socket.

15. Wipe excess cement from joint. A continuous bead of ce­ment will be visible around perimeter of a properly made
joint.

16. Handle pipe joints carefully until cement sets.

17. Horizontal portions of the venting system shall be
supported to prevent sagging. Space combustion air piping
and vent piping hangars as shown in Table 14. Support
pipes using perforated metal hanging strap or commercially
available hangars or straps designed to support plastic pipe.

18. Slope the vent and combustion air piping downward
towards furnace. A minimum slope of at least 1/4-in. (6

A14546

49

mm) per linear ft.(1-in (25 mm) per 4 ft.(1.2 M)) with no
sags between hangers is required. See Caution Box below.

!

CAUTION

FURNACE RELIABILITY HAZARD

Failure to follow this caution may result in nuisance short
cycling, frozen vent termination, and/or no heat.

Slope the vent and combustion air piping downward towards
furnace a minimum of 1/4-- in. (6 mm) per linear ft. of pipe.

19. Use appropriate methods to seal openings where combus­tion air pipe and vent pipe pass through roof or sidewall.

Optional Installation of the Vent Pipe

NOTE: DO NOT USE THIS TECHNIQUE FOR
POLYPROPYLENE VENTING SYSTEMS.

This option provides a disconnect point for the vent pipe. The vent
pipe must be cemented to the plastic vent pipe adapter to maintain
a sealed vestibule. See Fig. 52.

1. Insert a length of vent pipe through the casing into the
outlet of the vent elbow.

2. Slide the plastic vent pipe adapter over the length of the
vent pipe down to the furnace casing. Mark the pipe where
it is flush with the outlet of the adapter.

3. Remove the pipe from the furnace and the adapter and cut
off any excess pipe.

4. Clean and prime the end of the pipe that is flush with the
vent adapter with a primer that is appropriate for the type of
pipe being used.

5. Re--insert the pipe through the casing into the vent elbow.

6. Tighten the clamp around the outlet of the vent elbow.
Torque the clamp to 15 lb--in.

7. Apply cement to the end of the pipe and to the inside of the
plastic vent adapter.

VENT PIPE ADAPTER WITH GASKET
INSTALLED ON FURNACE VENT
PIPE IS CUT FLUSH WITH TOP OF
ADAPTER. PRIME AND CEMENT VENT
PIPE TO ADAPTER. ALLOW TO DRY
BEFORE INSTALLING VENT COUPLING.

8. Slide the adapter over the vent pipe and align the screw
holes in the adapter with the dimples in the furnace casing.

9. Pilot drill 1/8-- in. screw holes for the adapter in the casing
and secure the adapter to the furnace with sheet metal
screws.

10. Loosen the clamps on the rubber vent coupling.

11. Slide the end of the coupling with notches in it over the
standoffs in the vent pipe adapter.

12. Tighten the clamp of the coupling over the vent pipe
adapter. Torque the lower clamp around the vent pipe
adapter to 15 lb--in.

13. Pilot drill a 1/8--in. hole in the combustion air pipe adapter.

14. Complete the vent and combustion air pipe as shown in
“Install the Vent and Combustion Air Pipe.”

NOTICE

FOR POLYPROPYLENE VENTING SYSTEMS

When using polypropylene venting systems, all venting
materials used, including the vent terminations, must be from
the same manufacturer.

!

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in personal injury
or death.

DO NOT use cement to join polypropylene venting systems.
Follow the polypropylene venting system manufacturer’s
instructions for installing polypropylene venting systems.

ALIGN NOTCHES IN VENT PIPE
COUPLING OVER STAND-OFF
ON ADAPTER. TORQUE LOWER
CLAMP 15 LB-IN. WHEN REMAINING
VENT PIPE IS INSTALLED, TORQUE
UPPER CLAMP TO 15 LB-IN.

VENT PIPE FLUSH WITH ADAPTER

Fig. 52 -- Optional Vent Pipe Flush with Adaptor

VENT PIPE FLUSH SHOWING COUPLING

A13076

50

Installing the Vent Termination

Roof Termi nations

A roof termination of any type will require a 4-in. (102 mm)
flashing for a 2 in. (50 mm ND) concentric vent or a 5--in. diameter
(127 mm) flashing for a 3-in. (80 mm ND) concentric vent kit. For
two-pipe or single pipe vent systems, a flashing for each pipe of the
required diameter will be necessary.

It is recommended that the flashing be installed by a roofer or
competent professional prior to installing the concentric vent. The
terminations can be installed on a flat or pitched roof.

Concentric Vent

Single or multiple concentric vent must be installed as shown in
Fig. 56. Maintain the required separation distance between vents
or pairs of vents as shown in Fig. 56 and all clearance shown in
Fig. 54.

NOTE: Follow the instructions of the vent terminal manufacturer.
These instructions are provided as a reference, only.

Cut one 4 --in. (102 mm) diameter hole for 2--in. (50 mm ND) kit,
or one 5--in. (127 mm) diameter hole for 3 --in. (80 mm ND) kit in
the desired location.

Loosely assemble concentric vent/combustion air termination
components together using instructions in kit.

Slide assembled kit with rain shield REMOVED through hole in
wall or roof flashing.

NOTE: Do not allow insulation or other materials to accumulate
inside of pipe assembly when installing it through hole.

Disassemble loose pipe fittings. Clean and cement using same
procedures as used for system piping. DO NOT CEMENT

POLYPROPYLENE FITTINGS.
Two --Pipe and Single--Pipe Terminations

Single and two pipe vent must be installed as shown in Fig. 56 and

57. Maintain the required separation distance between vents or
pairs of vents as shown in Fig. 56 and 57 and all clearance shown
in Fig. 54 and 55 .

NOTICE

RECOMMENDED SUPPORT FOR VENT
TERMINATIONS

It is recommended that rooftop vent terminations in excess of
36 inches (1 M) in vertical length be supported by EITHER
the Direct Vent Te rmination Kit shown in Table 13 or by
field --supplied brackets or supports fastened to the structure.

Cut the required number of holes in the roof or sidewall for vent
and (when used) combustion air pipes. Sidewall holes for two-pipe
vent terminations should be side-by-side, allowing space between
the pipes for the elbows to fit on the pipes.

Holes in the roof for direct-- vent two--pipe terminations should be
spaced no more than 18 in. (457 mm) apart to help avoid vent gas
recirculation into combustion air intake.

Termination elbows will be installed after the vent and (if used)
combustion air pipe is installed.

Sidewall Terminations
Concentric Vent

NOTE: Follow the instructions of the vent terminal manufacturer.

These instructions are provided as a reference only.

Determine an appropriate location for termination kit using the

guidelines provided in section “Locating The Vent Termination” in
this instruction.

1. Cut one 4--in. diameter hole for 2--in. kit, or one 5--in. diam­eter hole for 3--in. kit.

2. Loosely assemble concentric vent/combustion air termina­tion components together using instructions in kit.

3. Slide assembled kit with rain shield REMOVED through
hole.

NOTE: Do not allow insulation or other materials to accumulate
inside of pipe assembly when installing it through hole.

4. Locate assembly through sidewall with rain shield posi­tioned no more than 1--in. (25 mm) from wall as shown in
Fig. 56.

5. Disassemble loose pipe fittings. Clean and cement using
same procedures as used for system piping. DO NOT CE-

MENT POLYPROPYLENE FITTINGS.

2-Pipe and 1-Pipe Vent Termination

NOTE: Follow the instructions of the vent terminal manufacturer.

These instructions are provided as a reference, only.

NOTICE

RECOMMENDED SUPPORT FOR VENT
TERMINATIONS

It is recommended that sidewall vent terminations in excess of
24 inches (.6 M) in vertical length be supported by EITHER
the Direct Vent Te rmination Kit shown in Table 13 or by
field --supplied brackets or supports fastened to the structure.

Determine an appropriate location for termination kit using the
guidelines provided in section “Locating The Vent Termination” in
this instruction.

1. Cut two holes, one for each pipe, of appropriate size for
pipe size being used.

2. Loosely install elbow in bracket (if used) and place assem­bly on combustion--air pipe.

3. Install bracket as shown in Fig. 56 and 58.

NOTE: For applications using vent pipe option indicated by
dashed lines in Fig. 56 and 57, rotate vent elbow 90_ from
position.

4. Disassemble loose pipe fittings. Clean and cement using
same procedures as used for system piping. DO NOT CE-

MENT POLYPROPYLENE FITTINGS.

(Direct Vent / 2-Pipe System ONLY)

When two or more furnaces are vented near each other, two vent
terminations may be installed as shown in Fig. 56, but next vent
termination, or pair of vent terminations, must be at least 36 in.
(914 mm) away from the first two terminations. It is important that
vent terminations be made as shown in Fig. 56 to avoid
recirculation of vent gases.

Inducer Outlet Restrictor

To improve efficiency and operation of 40K, 60K or 100K BTUH
input models on very short vent systems, an inducer outlet
restrictor is required to be installed on the outlet of the inducer
assembly. The outlet restrictor is shown in the footnote of Table 16

--Maximum Equivalent Vent Length. The outlet restrictor for 40K
models is shipped in the loose parts bag. See Table 16 for usage,
part numbers and sourcing of 60K and 100K inducer outlet
restrictors.
To determine if the outlet restrictor is required, see Table 16.

Failure to use an outlet restrictor on the 40K model when
required may result in flame disturbance or flame sense
lockout.

To install the outlet restrictor:

1. Remove the vent elbow from the inducer outlet.

2. Align the lock tabs on the outlet restrictor with the slots on
inside outlet of the inducer assembly.

3. Snap the outlet restrictor in place.

4. Re-install the vent elbow.

5. Torque vent elbow clamp 15-lb--in.

51

Winter

Design

Temp

°F

Table 15 – Maximum Allowable Exposed Vent Lengths in Unconditioned Space Insulation Table -- Ft. / M

Unit Size 40,000* BTUH 60,000 BTUH

Pipe Dia.

in.

20 20 20 20 20 50 45 20 60 50 20 30 30 25 20 75 65 60 20 85 75 65

0 10 5 5 20 25 20 20 30 25 15 15 10 10 20 40 30 25 20 45 40 30

-20 5 20 15 10 20 20 15 10 5 20 25 20 15 20 30 25 20

-40 15 10 5 15 15 10 5 20 15 15 10 20 20 15 10

Uninsulated

1½ 2 2½ 1½ 2 2½ 1½ 2 2½ 1½ 2 2½ 3 1½ 2 2½ 3 1½ 2 2½ 3

3/8-in. Insulation 1/2-in. Insulation

Uninsulated 3/8-in. Insulation 1/2-in. Insulation

Winter

Design

Temp

°F

Winter

Design

Temp

°F

Winter

Design

Temp

°F

Unit Size 80,000 BTUH

Pipe Dia.

in.

20 15 40 40 35 30 15 50 90 75 65 15 50 70 70 70

0 15 20 15 10 5 15 50 45 35 30 15 50 50 40 35

-20 15 10 5 15 35 30 20 15 15 40 30 25 15

-40 10 5 15 25 20 15 5 15 30 25 20 10

Unit Size 100,000 BTUH

Pipe Dia.

in.

20 20 50 40 35 20 80 95 80 20 80 105 90

0 20 20 15 10 20 55 45 35 20 65 55 45

-20 15 10 5 20 35 30 20 20 45 35 25

-40 10 5 20 25 20 10 20 30 25 15

Unit Size 120,000 BTUH 140,000 BTUH

Pipe Dia.

in.

20 10 50 40 10 75 95 10 75 105 5 55 50 5 65 105 5 65 125

0 10 20 15 10 55 45 10 65 50 5 25 15 5 65 50 5 65 60

-20 10 10 10 35 25 10 45 30 5 10 5 5 45 30 5 50 40

-40 10 5 10 25 15 10 30 20 5 5 5 30 20 5 35 25

1½ 2 2½ 3 4 1½ 2 2½ 3 4 1½ 2 2½ 3 4

2 2½ 3 4 2 2½ 3 4 2 2½ 3 4

Uninsulated

2½ 3 4 2½ 3 4 2½ 3 4 2½ 3 4 2½ 3 4 2½ 3 4

Uninsulated 3/8-in. Insulation 1/2-in. Insulation

Uninsulated 3/8-in. Insulation 1/2-in. Insulation

3/8-in. Insulation 1/2-in. Insulation

Uninsulated 3/8-in. Insulation 1/2-in. Insulation

Maximum Allowable Exposed Vent Length in Unconditioned Space (Metric)

Unit Size 40,000* BTUH 60,000 BTUH

Uninsulated

Pipe Dia.mm38 51 64 38 51 64 38 51 64 38 51 64 76 38 51 64 76 38 51 64 76

3/8-in. Insulation 1/2-in. Insulation

Uninsulated 3/8-in. Insulation 1/2-in. Insulation

Winter

Design

Temp

°C

Winter

Design

Temp

°C

Winter

Design

Temp

°C

Winter

Design

Temp

°C

* Pipe length (ft) specified for maximum pipe lengths located in unconditioned spaces. Pipes located in un conditioned space cannot exceed total allowable pipe
length calculated from Table 16.

† Insulation thickness based on R value of 3.5 per in.

-7 6.1 6.1 6.1 6.1 15.2 13.7 6.1 18.3 15.2 6.1 9.1 9.1 7.6 6.1 22.9 19.8 18.3 6.1 25.9 22.9 19.8

-18 3.0 1.5 1.5 6.1 7.6 6.1 6.1 9.1 7.6 4.6 4.6 3.0 3.0 6.1 12.2 9.1 7.6 6.1 13.7 12.2 9.1

-29 1.5 6.1 4.6 3.0 6.1 6.1 4.6 3.0 1.5 6.1 7.6 6.1 4.6 6.1 9.1 7.6 6.1

-40 4.6 3.0 1.5 4.6 4.6 3.0 1.5 6.1 4.6 4.6 3.0 6.1 6.1 4.6 3.0

Unit Size 80,000 BTUH

Pipe Dia.mm38 51 64 76 102 38 51 64 76 102 38 51 64 76 102

-7 4.6 12.2 12.2 10.7 9.1 4.6 15.2 27.4 22.9 19.8 4.6 15.2 21.3 21.3 21.3

-18 4.6 6.1 4.6 3.0 1.5 4.6 15.2 13.7 10.7 9.1 4.6 15.2 15.2 12.2 10.7

-29 4.6 3.0 1.5 4.6 10.7 9.1 6.1 4.6 4.6 12.2 9.1 7.6 4.6

-40 3.0 1.5 4.6 7.6 6.1 4.6 1.5 4.6 9.1 7.6 6.1 3.0

Unit Size 100,000 BTUH

Pipe Dia.mm51 64 76 102 51 64 76 102 51 64 76 102

-7 6.1 15.2 12.2 10.7 6.1 24.4 28.9 24.4 6.1 24.4 32.0 27.4

-18 6.1 6.1 4.6 3.0 6.1 16.8 13.7 10.7 6.1 19.8 16.7 13.7

-29 4.6 3.0 1.5 6.1 10.7 9.1 6.1 6.1 13.7 10.7 7.6

-40 3.0 1.5 6.1 7.6 6.1 3.0 6.1 9.1 7.6 4.6

Unit Size 120,000 BTUH 140,000 BTUH

Uninsulated

Pipe Dia.mm64 76 102 64 76 102 64 76 102 64 76 102 64 76 102 64 76 102

-7 3.0 15.2 12.2 3.0 22.9 28.9 3.0 22.9 32.0 1.5 16.7 15.2 1.5 19.8 32.0 1.5 19.8 38.1

-18 3.0 6.1 4.6 3.0 16.8 13.7 3.0 19.8 15.2 1.5 7.6 4.6 1.5 19.8 15.2 1.5 19.8 18.3

-29 3.0 3.0 3.0 10.7 7.6 3.0 13.7 9.1 1.5 3.0 1.5 1.5 13.7 9.1 1.5 15.2 12.2

-40 3.0 1.5 3.0 7.6 4.6 3.0 9.1 6.1 1.5 1.5 1.5 9.1 6.1 1.5 35 7.6

Uninsulated 3/8-in. Insulation 1/2-in. Insulation

Uninsulated 3/8-in. Insulation 1/2-in. Insulation

3/8-in. Insulation 1/2-in. Insulation

Uninsulated 3/8-in. Insulation 1/2-in. Insulation

52

NOTE: Maximum Equivalent Vent Length (MEVL) includes standard and concentric vent termination and does NOT include elbows.

Use Table 17 - Deductions from Maximum Equivalent Vent Length to determine allowable vent length for each application.

Unit Size 40,000

Pipe Dia. (in) 1½ 2 2½ 1½ 2 2½ 3 1½ 2 2½ 3 4 2 2½ 3 4 2½ 3 4

0--- 2000 40 155 185
2001--- 3000 35 150 175 95 165 185
3001--- 4000 30 135 160 16 90 155 175 115 155 175

Altitude

Altitude

(meters)

4001--- 4500
4501--- 5000 125 145 80 145 165 145 160

(feet)

5001--- 6000 20 120 130 75 140 155 41 100 135 150 140 155 155
6001--- 7000 15 110 120 13 70 130 145
7001--- 8000
8001--- 9000 90 95 5 60 115 125 33 80 110 115 50 115 125 43 120

9001--- 10000 5 80 85 N/A 55 105 115 30 75 100 105 45 100 115 39 115

Unit Size 40,000

Pipe Dia.

(mm)

0 --- 6 1 0 12.1 47.2 56.3

611--- 914 10.6 45.7 53.3 28.9 50.2 56.3

915--- 1219 9.1 41.1 48.7 4.8 27.4 47.2 53.3 35.0 47.2 53.3
1220--- 1370
1371--- 1524 38.1 44.1 24.3 44.1 50.2 44.1 48.7
1525--- 1829 6.0 36.5 39.6 22.8 42.6 47.2 12.4 30.4 41.1 45.7 42.6 47.2 47.2
1830--- 2134 4.5 33.5 36.5 3.9 21.3 39.6 44.1
2135--- 2438
2439--- 2743 27.4 28.9 1.5 18.2 35.0 38.1 10.0 24.3 33.5 35.0 15.2 35.0 38.1 13.1 36.5
2744--- 3048 1.5 24.3 25.9 NA 16.7 32.0 35.0 9.1 22.8 30.4 32.0 13.7 30.4 35.0 11.8 35.0

25

10

38 51 64 38 51 64 76 38 51 64 76 102 51 64 76 102 64 76 102

7.6

3.0

1

130 155

100 110 10 65 120 135 36 120 125

1

39.6 47.2

30.4 33.5 3.0 19.8 36.5 41.1 10.9 36.5 38.1

NOTES:

1. Inducer Outlet Restrictor disk (P/N 337683 ---401; 1.25 ---in. (32 mm) Dia.) shipped in the loose parts bag or available through Replacement Components
required under 10 ---ft. (3 M) TEVL in all or ientations. Required for installations fr om 0 --- 2000 (0 to 610 M) above sea level . Failure to use an outlet restric­tor may result in fl ame disturbances or flame sense lock ---out.

2. Inducer Outlet Restrictor disk (P/N 337683 ---401; 1.25 ---in. (32 mm) Dia.) available through Replacement Components required for no greater than 5 --- f t . ( 1. 5
M) TEVL in downflow and horizontal orientations only. Required for installations from 0 --- 2000 (0 to 610 M) above sea level.

3. Inducer Outlet Restrictor disk (P/N 337683 ---402; 1.50 ---in. (38 mm) Dia.) available through Replacement Components required for no greater than 5 --- f t . ( 1. 5
M) TEVL in downflow and horizontal orientations only. Required for installations from 0 --- 2000 (0 to 610 M) above sea level.

Table 16 – Maximum Equivalent Vent Length -- Ft.

20

15

6.0

4.5

2

60,000

100 175 200 15 55 130 175 200 20 80 175 200

85 150 170

Maximum Equivalent Vent Length --- Meters

2

60,000

30.4 53.3 60.9 4.5 16.7 39.6 53.3 60.9 6.0 24.3 53.3 60.9

25.9 45.7 51.8

10

N/A

3.0

NA

80,000 100,000

125 165 185

49

44 110

38

14.9

13.4 33.5

11.5

150 165

125 140 60 135 145 50 140

90

80,000 100,000

38.1 50.2 56.3

45.7 50.2

38.1 42.6 18.2 41.1 44.1 15.2 42.6

27.4

15 75

70 170

10

65

55 125 135 46 130

N/A

4.5 22.8

21.3 51.8

3.0

19.8

16.7 38.1 41.1 14.0 39.6

NA

3

165 185 70 175

175 5 65 165

155

150 165

3

50.2 56.3 21.3 53.3

53.3 1.5 19.8 50.2

47.2

45.7 50.2

10

N/A

3.0

NA

120,000

75 185

60

120,000

22.8 56.3

18.2

160

48.7

ELBOW CONFIGURATIONS

VENT TERMINAL CONFIGURATIONS

Concentric

Long

Medium

Mitered

Standard 2-in., 3-in., or
optional 4-in. termination.

Pipe Diameter (in): 1-1/2 2 2-1/2 3 4
Mitered 90º Elbow 8 (2.4) 8 (2.4) 8 (2.4) 8 (2.4) 8 (2.4)
Medium Radius 90º Elbow 5 (1.5) 5 (1.5) 5 (1.5) 5 (1.5) 5 (1.5)
Long Radius 90º Elbow 3 (0.9) 3 (0.9) 3 (0.9) 3 (0.9) 3 (0.9)
Mitered 45º Elbow 4 (1.2) 4 (1.2) 4 (1.2) 4 (1.2) 4 (1.2)
Medium Radius 45º Elbow 2.5 (0.8) 2.5 (0.8) 2.5 (0.8) 2.5 (0.8) 2.5 (0.8)
Long Radius 45º Elbow 1.5 (0.5) 1.5 (0.5) 1.5 (0.5) 1.5 (0.5) 1.5 (0.5)
Tee 16 (4.9) 16 (4.9) 16 (4.9) 16 (4.9) 16 (4.9)
Concentric Vent Termination NA 0 (0.0) NA 0 (0.0) NA
Standard Vent Termination 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0) 0 (0.0)

NOTES:

1. Use only the smallest diameter pipe possible for venting. Over ---sizing may cause flame disturbance or excessive vent terminal icing or freeze ---up.

2. NA --- Not allowed. Pressure switch will not close, or flame disturbance may result.

3. Vent sizing for Can a dian installations over 4500 ft. (1370 M) above sea level are subject to acceptance by the local authorities having jurisdiction.

4. Size both the combustion air and vent pipe independently, then use the larger size for both pipes.

5. Assume the two 45_ elbows equal one 90_ elbow. Wide radius elbows are desirable and may be required in some cases.

6. Elbow and pipe sections within the furnace casing and at the vent termination should not be included in vent length or elbow count.

7. T he minimu m pipe length is 5 ft. (2 M) linear feet (meters) for all applications.

8. U se 3 -- -in. (76 mm) diameter vent termination kit for installations requiring 4 ---in. (102 mm) diameter pipe.

Table 17 – Deductions from Maximum Equivalent Vent Length -- Ft. (M)

A13110

53

Venting System Length Calculations

The Total Equivalent Vent Length (TEVL) for EACH combustion air or vent pipe equals the length of the venting system, plus the equivalent
length of elbows used in the venting system from Table 17.

Standard vent terminations or factory accessory concentric vent terminations count for zero deduction.
See vent system manufacturer’s data for equivalent lengths of flexible vent pipe or other termination systems. DO NOT ASSUME that one

foot of flexible vent pipe equals one foot of straight PVC/ABS DWV vent pipe.
Compare the Total Equivalent Vent Length to the Maximum Equivalent Vent Lengths in Table 16.

Example 1

A direct-vent 60,000 BTUH furnace installed at 2100 ft. (640M). Venting system includes FOR EACH PIPE:
70 feet (22 M) of vent pipe, 65 feet (20 M) of combustion air inlet pipe, (3) 90º long-radius elbows, (2) 45º long-radius elbows, and a factory
accessory concentric vent kit.

Can this application use 2” (50 mm ND) PVC/ABS DWV vent piping?

Measure the required linear length of air inlet and
vent pipe; insert the longest of the two here

Add equiv length of (3) 90º long-radius elbows
(use the highest number of elbows for either the
vent or inlet pipe)

Add equiv length of (2) 45º long-radius elbows
(use the highest number of elbows for either the
vent or inlet pipe)

Add equiv length of factory concentric vent term 0ft.

Add correction for flexible vent pipe, if any 0ft.

Total Equivalent Vent Length (TEVL)

3 x

2 x

3ft.

(0.9 M)

1.5 ft.

(0.5 M)

70 ft.

(22 M)

9ft.

=

(2.7 M)

3ft.

=

(0.9 M)

82 ft.

(25 M)

Use length of the longer of the vent
or air inlet piping system

From Table 17

From Table 17

From Table 17
From Vent Manufacturer’s

instructions; zero for PVC/ABS DWV

Add all of the above lines

Maximum Equivalent Vent Length (MEVL)

Is TEVL less than MEVL? YES Therefore, 2” pipe MAY be used

95 ft.

(29 M)

For 2” p ipe from Table 16

Example 2

A direct-vent 60,000 BTUH furnace installed at 2100 ft. (640M). Venting system includes FOR EACH PIPE:
100 feet (30 M) of vent pipe, 95 feet (29 M) of combustion air inlet pipe, (3) 90º long-radius elbows, and a polypropylene concentric vent kit.
Also includes 20 feet (6.1 M) of flexible polypropylene vent pipe, included within the 100 feet (30 M) of vent pipe.

VERIFY FROM POLYPROPYLENE VENT MANUFACTURER’S INSTRUCTIONS for the multiplier correction for flexible vent pipe.
Can this application use 60mm o.d. (2”) polypropylene vent piping? If not, what size piping can be used?

Measure the required linear length of RIGID air inlet and vent pipe; insert
the longest of the two here: 100 ft. Of rigid pipe --- 20 ft. Of flexible pipe

Add equiv length of (3) 90º long-radius elbows
(use the highest number of elbows for either the
vent or inlet pipe)

Add equiv length of 45º long-radius elbows
(use the highest number of elbows for either the
vent or inlet pipe)

Add equiv length of factory concentric vent term 9 x

Add correction for flexible vent pipe, if any 2* x

* VERIFY FROM VENT MANUFACTURER’S INSTRUCTIONS; For example only, assume 1 meter of flexible 60mm (2”) or 80mm (3”)
polypropylene pipe equals 2.0 meters (6.5 ft.) of PVC/ABS pipe.

Total Equivalent Vent Length (TEVL)

Maximum Equivalent Vent Length (MEVL)

Is TEVL less than MEVL? NO

3 x

0 x =

5ft.

(1.5 M)

3.3 ft

(0.9 M)

20 ft.

(6.1 M)

= 80 ft.

(24 M)

15 ft.

=

(4.6 M)

0ft.

(0 M)

30 ft.

=

(9 M)

40 ft.

=

(12.2 M)

165 ft.

(50 M)

95 ft.

(29 M)

Use length of the longer of the vent
or air inlet piping system

Example from polypropylene vent

manufacturer’s instructions, Verify from vent

manufacturer’s instructions.

Add all of the above lines

For 2” p ipe from Table 16

Therefore, 60mm (2”) pipe may NOT be
used; try 80mm (3”)

Maximum Equivalent Vent Length (MEVL)

Is TEVL less than MEVL? YES Therefore, 80mm (3”) pipe MAY be used

185 ft.

(57 M)

For 3” p ipe from Table 16

54

A190032

Fig. 53 -- Inside Corner Termination

Inside Corner Terminations

Inside corner vent terminations are permitted provided that:

S Only two exterior walls come together to form an angle of 90 degrees to 135 degrees. There are no other exterior walls

attached to either wall to form an alcove.

S The clearance distances apply when the vent is at least 3 feet (1 meter) from, but not more than 6 feet (2 meters) away from an

inside corner.

S For vent terminations located more than 6 feet (2 meters) from an inside corner, refer to the appropriate Direct Vent Clearance

Table for all two pipe terminations or Non---Direct Vent Clearance Table for all single pipe terminations.

S The clearance distances to items between the vent termination and the outside corner, refer to the appropriate Direct Vent

Clearance Table for all two pipe terminations or Non --- Direct Vent Clearance Table for all single pipe terminations.

For clearance distances when vent termination is located more than 6 ft. (2 M) away from an inside corner, refer to the appropriate Direct Vent or
Non-- -Direct Vent Clearance Table.

Clearance description when termination is at least 3 ft. (1 M) away and not more than 6 ft. (2 M) away from an inside corner.

Clearance above grade, veranda, porch, deck, balcony or anticipated snow level 12--- in. (305 mm)

Clearance to a permanently closed window on either Wall A or Wall B 12--- in. (305 mm)

Vertical clearance to a soffitt located above the vent termination within a horizontal distance of 2 ft. (61 cm) from the centerline of
the vent termination

Clearance to a ventilation exhaust (including HRV/ERV) on either Wall A or Wall B 12--- in. (305 mm)

Clearance above paved sidewalk or paved driveway located on public property 7ft.(2.1M)

Clearance under a veranda, porch, deck, or balcony N.P.*

No operable windows, doors or intakes of any type are permitted on Wall B between the vent termination and the inside corner when the vent
termination is at least 3 ft. (1 M) away and not more than 6 ft. (2 M) away from an inside corner .

The following items on Wall A must be located at least 3 ft. (1 M) away from the inside corner when a vent te rmination is located on Wall B and the
vent termination is at least 3 ft. (1 M) away or not more than 6 ft. (2 M) away from an inside corner.

A window or door that may be opened

The centerline extended above electrical meter or gas service regulator assembly

A service regulator vent outlet

The centerline of a dryer or water heater vent, or other appliance’s vent intake

A non ---mechanical air supply inlet

6ft.(2M)

Clearance distances shown for Wall A are measured horizontally from the exit of the termination on Wall B to the closest edge of the item shown
below.

Clearance to a mechanical air supply (including HRV/ERV) inlet unless termination is 3 ft. (1 M) above the horizontal line of the
intake

For clearance distances from a vent termination to the outside corner of the wall, refer to the appropriate Direct Vent or Non --- Direct Vent Clearance
Ta b l e

*N.P. = Not Permitted
*N/A = Not Applicable

10 ft. (3 M)

55

V

V

NOTE: The following is based upon National codes for gas appliances and is provided as a reference.
Refer to local codes which may supersede these standards and/or recommendations.

Item Clearance Description

Clearance above grade, veranda, porch, deck, balcony

A

B Clearance to a window or door that may be opened

C Clearance to a permanently closed window

Vertical clearance to a ventilated soffit located above
the terminal within a horizontal distance of 2 feet (61

D

E Clearance to an unventilated soffit
F Clearance to an outside corner

G Clearance to an inside corner

Clearance to each side of the centerline extended above

H

electrical meter or gas service regulator assembly

I Clearance to service regulator vent outlet 3ft. (.9 M) SeeNote4.

Clearance to non—mechanical air supply inlet to building

J

or the combustion air inlet to any other appliance

K Clearance to a mechanical air supply inlet 6 ft. (1.8 M) 3ft (.9 M) above if within 10 ft. (3 M) horizontally

L Clearance under a veranda, porch, deck, or balcony

Clearance to each side of the centerline extended above
or below vent terminal of the furnace to a dryer or water

M

heater vent, or other appliance’s direct vent intake or

Furnace combustion air intake clearance to a water

heater vent, dryer vent or other types of appliance

N

0 Clearance from a plumbing vent stack 3ft.(.9M) 3 ft. (.9 M)

Clearance above paved sidewalk or paved driveway

P

> greater than, ≥ greater than or equal to, < less than, ≤ less than or equal to

or anticipated snow level

cm) from the centerline of the terminal

exhaust

exhaust.

located on public property

12 in. (305 mm) for appliances >10,000 Btuh (3 kW)

36 in. (914 mm) for appliances >100,000 Btuh (30 kW)

For clearances not specified in ANSI Z223.1/NFPA 54 or CAN/CSA B149.1, clearances shall be in accordance with local

12 in. (305 mm) for appliances >10,000 Btuh(3 kW)

36 in. (914 mm) for appliances >100,000 Btuh (30 kW)

Permitted only if veranda, porch, deck, or balcony is fully open on a

Vent shall not terminate above a sidewalk or paved driveway that is

located between two single family dwellings and serves both

Canadian Installations

(per CAN/CSA B149.1)

12 in. (305 mm)

18 in. (457 mm) above roof surface.

and </=100,000 Btuh ( 30 kW),

installation codes and the requirements of the gas supplier and the manufacturer’s installation instructions.

3 ft. (.9 M) within 15 ft. (4.6 M)

above the meter/regulator assembly.

and </= 100,000 Btuh ( 30 kW),

12 in. (305 mm).

minimum of two sides beneath the floor.

12 in. (305 mm) 12 in. (305 mm)

3ft.(.9M) 3 ft. (.9 M)

7 ft. (2.1 M)

dwellings.

(1 )

(per ANSI Z223.1/NFPA 54)

9 in. (229 mm) for appliances >10,000 Btuh (3 kW)

and </= 50,000 Btuh ( 15 kW),

12 in. (305 mm) for appliances >50,000 Btuh (15kW)

Manufacturer ’s Recommendation: See Notes 3-8.

3ft.(.9M)within15ft.(4.6M)

above the meter/regulator assembly.

9 in. (9 mm) for appliances >10,000 Btuh (3 kW)

and </= 50,000 Btuh (15 kW),

12 in.(305 mm) for appliances >50,000 Btuh (15kW)

Manufacturer ’s Recommendation: See Notes 3-8.

Manufacturer ’s Recommendation: See Notes 3-8.

U.S. Installations

12 in. (305 mm)

SeeNote4.

SeeNote4.

Notes:

1 In accordance with the current CAN/CSA B149.1, Natural Gas and Propane Installation Code.
2 In accordance with the current ANSI Z223.1/NFPA 54, National Fuel Gas Code
3 NOTE: This table is based upon National codes for gas appliances, and are provided as a reference.

Refer to Local codes which may supersede these standards and/or recommendations.

4 For clearances not specified in ANSI Z223.1/NFPA 54 or CAN/CSA B 149.1, clearances shall be in accordance with local installation codes and the requirements

of the gas supplier and the manufacturer’s installation instructions.

5 When locating vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the combustion

products of adjacent vents. Recirculation can cause poor combustion, inlet condensate problems, vent termination icing, and/or and accelerated corrosion of the

heat exchangers.
6 Design and position vent outlets to avoid ice build-up on and moisture damage to surrounding surfaces.
7 The vent for this appliance shall not terminate:

a. Near soffit vents of crawl space vents or other areas where condensate or vapor could create a nuisance or hazard or property damage; or
b. Where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valves, or other equipment.

8 Avoid venting under a deck or large overhang. Recirculation could occur and cause performance or system problems. Ice build-up may occur.

(2 )

Fig. 54 -- Direct Vent Termination Clearance

A12326

56

V

V

NOTE: The following is based upon National codes for gas appliances and is provided as a reference.
Refer to local codes which may supersede these standards and/or recommendations.

Item Clearance Description

Clearance above grade, veranda, porch, deck, balcony or

A

B Clearance to a window or door that may be opened

C Clearance to a permanently closed window

Vertical clearance to a ventilated soffit located above the

terminal within a horizontal distance of 2 feet (61 cm) from

D

E Clearance to an unventilated soffit
F Clearance to an outside corner

G Clearance to an inside corner

Clearance to each side of the centerline extended above

H

I Clearance to service regulator vent outlet 3ft. (.9 M) SeeNote4.

J

K Clearance to a mechanical air supply inlet 6 ft. (1.8 M) 3ft (.9 M) above if within 10 ft. (3 M) horizontally

L Clearance under a veranda, porch, deck, or balcony

M

N

0 Clearance from a plumbing vent stack 3 ft. (.9 M) 3 ft. (.9 M)

P

> greater than, ≥ greater than or equal to, < less than, ≤ less than or equal to

electrical meter or gas service regulator assembly

Clearance to non—mechanical air supply inlet to building or

the combustion air inlet to any other appliance

Clearance to each side of the centerline extended above or

below vent terminal of the furnace to a dryer or water heater

vent, or other appliance’s direct vent intake or exhaust

Clearance above paved sidewalk or paved driveway located

anticipated snow level

the centerline of the terminal

Clearance to a moisture exhaust duct

(dryer vent, spa exhaust, etc.)

on public property

12 in. (305 mm) for appliances >10,000 Btuh (3 kW)

36 in. (914 mm) for appliances >100,000 Btuh (30 kW)

For clearances not specified in ANSI Z223.1/NFPA 54 or CAN/CSA B149.1, clearances shall be in accordance with local

12 in. (305 mm) for appliances >10,000 Btuh(3 kW)

36 in. (914 mm) for appliances >100,000 Btuh (30 kW)

Permitted only if veranda, porch, deck, or balcony is fully open

Vent shall not terminate above a sidewalk or paved driveway

that is located between two single-family dwellings and serves

Canadian Installations

(per CAN/CSA B149.1)

12 in. (305 mm)

18 in. (457 mm) above roof surface.

and </=100,000 Btuh ( 30 kW),

installation codes and the requirements of the gas supplier and the manufacturer’s installation instructions.

3 ft. (.9 M) within 15 ft. (4.6 M)

above the meter/regulator assembly.

and </= 100,000 Btuh ( 30 kW),

12 in. (305 mm).

on a minimum of two sides beneath the floor.

12 in. (305 mm) 12 in. (305 mm)

12 in. (305 mm) See Note 4 12 in. (305 mm) See Note 4

7 ft. (2.1 M).

both dwellings.

(1 )

Manufacturer ’s Recommendation: See Notes 3-8.

(per ANSI Z223.1/NFPA 54)

4ft. (1.2M) below or to the side of the opening,

1 ft (.3M) above the opening.

Manufacturer ’s Recommendation: See Note 8.

3 ft. (.9 M) within 15 ft. (4.6 M)

above the meter/regulator assembly.

4ft. (1.2M) below or to the side of the opening,

1 ft (.3M) above the opening.

Manufacturer ’s Recommendation: See Note 8

Manufacturer ’s Recommendation: See Notes 3-8.

U.S. Installations

12 in. (305 mm)

SeeNote4.

7ft. (2.1M)

Notes:

1 In accordance with the current CAN/CSA B149.1, Natural Gas and Propane Installation Code.
2 In accordance with the current ANSI Z223.1/NFPA 54, National Fuel Gas Code
3 NOTE: This table is based upon National codes for gas appliances, and are provided as a reference.

Refer to Local codes which may supersede these standards and/or recommendations.

4 For clearances not specified in ANSI Z223.1/NFPA 54 or CAN/CSA B 149.1, clearances shall be in accordance with local installation codes and the requirements

of the gas supplier and the manufacturer’s installation instructions.
5 When locating vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the combustion

products of adjacent vents. Recirculation can cause poor combustion, inlet condensation problems, vent termination icing, and/or accelerated corrosion of the heat

exchangers.
6 Design and position vent outlets to avoid ice build-up on and moisture damage to surrounding surfaces.
7 The vent for this appliance shall not terminate:

a. Near soffit vents of crawl space vents or other areas where condensate or vapor could create a nuisance or hazard or property damage; or
b. Where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valves, or other equipment.

8 These National standards apply to all non-direct-vent gas appliances. Contact Local code officials for additional requirements and/or exclusions.

(2 )

Fig. 55 -- Ventilated Combustion Air and Non --Direct Vent Termination Clearance

A12325

57

¾ in. (222mm) for 3 in. (76mm)

¾ in. (172mm) for 2 in. (51mm)

12 in. (305mm) min. separation
between bottom of combustion
air and bottom of vent (Typ.)

Fig. 56 -- Combustion Air and Vent Pipe Termination for Direct Vent (2-- Pipe) System

Roof Termination (Preferred)

Ven t

A13305

(305mm)

Maintain 12 in .

minimum clearance

above highest anticipated

snow level maximum of

24 in. (610mm) above roof.

Abandoned masonry
used as raceway
(per code)

12 in. min. (305 mm)from

overhang or roof

Sidewall Termination

with Straight Pipe (preferred)

Maintain 12 in. (305mm)
minimum clearance
above highest anticipated
snow level or grade
whichever is greater

90°

Side wall termination
with 2 elbows (preferred)

12 in. (305 mm) min. from

overhang or roof

Maintain 12 in. (305mm)
minimum clearance
above highest anticipated
snow level or grade
whichever is greater.

6 in. (152mm) minimum clearance

between wall and end of vent pipe.

10 in. (254mm) maximum pipe length

Fig. 57 -- Vent Pipe Termination for Non --Direct Vent and Ventilated Combustion Air System

A05091

58

Fig. 58 -- Alberta and Saskatchewan Vent Termination

A13078

Fig. 59 -- Vent Terminations for Ventilated Combustion Air

59

START--UP, ADJUSTMENT, AND SAFETY

CHECK

NOTICE

Important Installation and Start--up Procedures

Failure to follow this procedure may result in a nuisance
smoke or odor complaint.

The manifold pressure, gas rate by meter clocking,
temperature rise and operation must be checked after
installation. Minor smoke and odor may be present
temporarily after start--up from the manufacturing process.
Some occupants are more sensitive to this minor smoke and
odor. It is recommended that doors and windows be open
during the first heat cycle.

General

1. Furnace must have a 115-v power supply properly connect­ed and grounded.

NOTE: Proper polarity must be maintained for 115-v wiring.
Control status indicator light flashes rapidly and furnace does not
operate if polarity is incorrect or if the furnace is not grounded.

2. Thermostat wire connections at terminals R, W/W1, G, and
Y/Y2 must be made at 24-v terminal block on furnace con­trol.

3. Natural gas service pressure must not exceed 0.5 psig (14­in. w.c., 350 Pa), but must be no less than 0.16 psig (4.5-in.
w.c., 1125 Pa).

4. Blower door must be in place to complete 115-v electrical
circuit and supply power to furnace components.

!

CAUTION

UNIT OPERATION HAZARD

Failure to follow this caution may result in intermittent unit
operation or performance dissatisfaction.

These furnaces are equipped with a manual reset limit
switch in burner assembly. This switch opens and shuts off
power to the gas valve if an overheat condition (flame
rollout) occurs in the burner assembly/enclosure. Correct
inadequate combustion-- air supply, improper gas pressure
setting, improper burner or gas orifice positioning, or
improper venting condition before resetting switch. DO
NOT jumper this switch.

Before operating furnace, check flame rollout manual reset switch
for continuity. If necessary, press button to reset switch.

EAC-1 terminal is energized whenever blower operates. HUM
terminal is only energized when the blower is energized in heating.

Setup Switches

There are two sets of setup switches on the furnace control board.
These switches configure the furnace for correct application
requirement. They also select the airflow settings for Air
Conditioning and Continuous Fan airflows.

The Setup Switch locations are shown and described on Fig. 65.
The setup switches are also shown on the unit wiring label.

Setup Switches (SW1)

The furnace control has 8 setup switches that may be set to meet
the application requirements. Refer to the Adjustments section for

setup switch configurations. To set these setup switches for the
appropriate requirement:

1. Remove blower door.

2. Locate setup switches on furnace control.

3. Configure the setup switches as necessary for the
application.

4. Replace blower door.

NOTE: If a bypass humidifier is used, setup switch SW1-4
(Comfort/Efficiency) should be in OFF=Efficiency position. This
compensates for the increased temperature in return air resulting
from bypass.

Air Conditioning (A/C) Setup Switches (SW2--6, 7, 8)

The air conditioning setup switches are used to match furnace
airflow to required cooling airflow or high stage cooling airflow
when a two--stage outdoor unit is used. Refer to the Adjustments
section for setup switch configurations.

To set the desired cooling airflow:

1. Remove blower door.

2. Locate A/C setup switches on furnace control.

3. Determine air conditioning tonnage used.

4. Configure the switches for the required cooling airflow.

NOTE: Incorrect airflow caused by improper A/C switch setup
may cause condensate blow-off or a frozen indoor coil in the
cooling mode.

5. Replace blower door.

Continuous Fan (CF) Setup Switches (SW2--3, 4, 5)

The CF setup switches are used to select desired airflow when
thermostat is in continuous fan mode or to select low-cooling
airflow for two--speed cooling units. Refer to the Adjustments
section for setup switch configurations. To set desired cooling
airflow:

1. Remove blower door.

2. Locate CF setup switches on furnace control.

3. Determine air conditioning tonnage used for low-cooling
(when used) or desired continuous fan airflow.

4. Configure the switches for the required airflow.

5. Replace blower door.

Setup Switches (SW2--1, 2)

The furnace control has two additional setup switches labeled
SW2--1,2.

Setup switch SW2--1 is used for twinning on approved models.
SW2--2 is used to adjust airflow. Refer to the Adjustments section

for setup switch configurations.

Refer to Fig. 65 for configuration of SW2 airflow options.

1. Remove blower door.

2. Locate setup switch SW2 on furnace control.

3. Configure the switches as necessary for the application.

4. Replace blower door.

Prime Condensate Trap with Water

!

WARNING

CARBON MONOXIDE POISONING HAZARD

Failure to follow these warnings could result in personal injury
or death.

Failure to use a properly configured trap or NOT
water-- priming trap before operating furnace may allow
positive pressure vent gases to enter the structure through drain
tube. Vent gases contain carbon monoxide which is tasteless
and odorless.

60

!

CAUTION

UNIT OPERATION HAZARD

Failure to follow this caution may result in intermittent unit
operation or performance satisfaction.

Condensate trap must be PRIMED or proper draining may
not occur. The condensate trap has two internal chambers
which can ONLY be primed by pouring water into the
inducer drain side of condensate trap.

Adjustments

!

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal
injury, death and/or property damage.

DO NOT bottom out gas valve regulator adjusting screw.
This can result in unregulated manifold pressure and result
in excess overfire and heat exchanger failures.

1. Remove upper and middle collector box drain plugs oppo­site of the condensate trap. See Fig. 60.

2. Connect field-supplied 5/8-in. (16 mm) ID tube with at­tached funnel to upper collector box drain connection. See
Fig. 60.

A11315

Fig. 60 -- Priming Condensate Trap

3. Pour one quart (liter) of water into funnel/tube. Water
should run through collector box, overfill condensate trap,
and flow into open field drain.

4. Remove funnel; replace collector box drain plug.

5. Connect field-supplied 5/8-in. (16 mm) ID tube to middle
collector box drain port.

6. Pour one quart (liter) of water into funnel/tube. Water
should run through collector box, overfill condensate trap,
and flow into open field drain.

7. Remove funnel and tube from collector box and replace col­lector box drain plug.

Purge Gas Lines

If not previously done, purge the lines after all connections have
been made and check for leaks.

!

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal
injury, death, and/or property damage.

Never purge a gas line into a combustion chamber. Never
test for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection
of leaks to check all connections. A fire or explosion may
result causing property damage, personal injury or loss of
life.

!

CAUTION

FURNACE DAMAGE HAZARD

Failure to follow this caution may result in reduced furnace
life.

DO NOT redrill orifices. Improper drilling (burrs,
out--of--round holes, etc.) can cause excessive burner noise
and misdirection of burner flames. This can result in flame
impingement of heat exchangers, causing failures. See Fig.

61.

BURNER

ORIFICE

A93059

Fig. 61 -- Orifice Hole

For proper operation and long term reliability, the Furnace input
rate must be within +/--2 percent of input rate on furnace rating
plate, or as adjusted for altitude.

The gas input rate on rating plate is for installations at altitudes up
to 2000 ft. (609.6M).

NOTICE

The NATURAL GAS manifold pressure adjustments in Table
21 compensate for BOTH altitude AND gas heating value.
DO NOT apply an additional derate factor to the pressures
shown in Table 21. The values in this table are NOT
referenced to sea level; they are AS--MEASURED AT
ALTITUDE.

The heating content of natural gas at altitude may already
provide for a reduction in capacity of the furnace. Be sure to
obtain the expected in--season gas heating value of the gas
from the gas supplier BEFORE making any adjustments for
capacity or altitude. Refer to Table 21. No adjustments to the
furnace may be necessary at altitude for certain gas heating
values.

Refer to the instructions provided in the factory-- specified
LP/Propane conversion kit for instructions for setting gas
manifold pressures for LP/Propane applications.

61

In the USA, the input rating for altitudes above 2000 ft. (609.6M)
must be reduced by 2 percent for each 1000 ft. (304.8M) above sea
level. Refer to Table 18. The natural gas manifold pressures in
Table 21 adjust for BOTH altitude and natural gas heating value.

In Canada, the input rating must be reduced by 5 percent for
altitudes of 2000 ft. (609.6M) to 4500 ft. (1371.6M) above sea
level. The natural gas manifold pressures in Ta b l e 21 adjust for
BOTH altitude and natural gas heating value.

NOTE: For Canadian altitudes of 2000 to 4500 ft. (609.6 to

1371.6M), use USA altitudes of 2001 to 3000 ft. (609.6 to

914.4M).

To adjust manifold pressure to obtain the proper input rate, first,
determine if the furnace has the correct orifice installed. At higher
altitudes or different gas heat contents, it may be necessary to
change the factory orifice to a different orifice. Tables have been
provided in the furnace installation instructions to match the
required orifice to the manifold pressure to the heat content and
specific gravity of the gas. To do this:

1. Obtain average yearly gas heat value (at installed altitude)
from local gas supplier.

2. Obtain average yearly gas specific gravity from local gas
supplier.

3. Find installation altitude in Ta b l e 21.

4. Find closest natural gas heat value and specific gravity in
Table 21. Follow heat value and specific gravity lines to
point of intersection to find orifice size and low--and high-­heat manifold pressure settings for proper operation.

5. Check and verify burner orifice size in furnace. NEVER
ASSUME ORIFICE SIZE. ALWAYS CHECK AND
VERIFY.

NOTICE

If orifice hole appears damaged or it is suspected to have been
redrilled, check orifice hole with a numbered drill bit of
correct size. Never redrill an orifice. A burr--free and squarely
aligned orifice hole is essential for proper flame characteristics.

6. Replace orifice with correct size, if required by Ta b l e 21.
Use only factory--supplied orifices. See EXAMPLE 1.

EXAMPLE 1

EXAMPLE: 0 -- 2000 ft. (0 -- 609.6M) altitude
Heating value = 1050 Btu/cu ft.

Specific gravity = 0.62
Therefore: Orifice No. 44
* Furnace is shipped with No. 44 orifices. In this example, all main

burner orifices are the correct size and do not need to be changed to
obtain proper input rate.

Manifold pressure: 3.4--in. w.c. for high heat, 1.4--in. w.c. for low
heat

NOTE: To convert gas manifold Table pressures to Pascals,
multiply the in. w.c. value by 249.1 Pa/in. w.c. (1 in. w.c. = 249.1
Pa).

Check Inlet Gas Pressure

The inlet gas pressure must be checked with the furnace operating
in maximum heat. This is necessary to make sure the inlet gas
pressure does not fall below the minimum pressure of 4.5 in. w.c.
for natural gas. The maximum inlet gas pressure is 13.6 in. of water
column. If the inlet pressure is too low, you will not be able to
adjust the manifold pressure to obtain the proper input rate. To
check the inlet gas pressure:

1. Make sure the gas supply is turned off to the furnace and at
the electric switch on the gas valve.

2. Loosen set screw on inlet pressure tap no more than one full
turn with a 3/32--in. hex wrench or remove the 1/8 in. NPT
plug from the inlet pressure tap on the gas valve.

3. Connect a manometer to the inlet pressure tap on gas valve.

4. Turn on furnace power supply.

5. Turn gas supply manual shutoff valve to ON position.

6. Turn furnace gas valve switch to ON position.

7. Jumper the R to W/W1 and W2 thermostat connections at
the furnace control board.

8. When main burners ignite, confirm inlet gas pressure is
Between 4.5 in. w.c. and 13.6 in. w.c.

9. Remove jumper across thermostat connections to terminate
call for heat. Wait until the blower off delay is completed.

10. Turn furnace gas valve electric switch to OFF position.

11. Turn gas supply manual shutoff valve to OFF position.

12. Turn off furnace power supply.

13. Remove manometer from the inlet pressure tap of the gas
valve.

!

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal
injury, death, and/or property damage.

Inlet pressure tap set screw must be tightened and 1/8--in.
NPT pipe plug must be installed to prevent gas leaks.

14. Tighten set screw on inlet pressure tap with 3 /32--in. hex
wrench, or if 1/8--in. NPT plug was removed, apply pipe
dope sparingly to end of plug and re--install in the gas
valve.

Adjust Manifold Pressure

1. Adjust manifold pressure to obtain low fire input rate. See
Fig. 33.

a. Turn gas valve ON/OFF switch to OFF.

b. Loosen set screw on manifold tower pressure tap no

more than one full turn with a 3/32-- in. hex wrench, or
remove the 1/8 inch NPT plug from the manifold
pressure tap on the gas valve.

c. Connect a water column manometer or similar device to

manifold pressure tap.

d. Turn gas valve ON/OFF switch to ON.

e. Move setup SW1--2 on furnace control to ON position to

lock furnace in low--heat operation. See Fig. 65 and 40.

f. Manually close blower door switch.

g. Jumper R and W/W1 thermostat connections on control to

start furnace. See Fig. 40.

h. Remove regulator adjustment cap from low heat gas valve

pressure regulator and turn low--heat adjusting screw (3/16
or smaller flat--tipped screwdriver) counterclockwise (out)
to decrease input rate or clockwise (in) to increase input
rate. See Fig. 33.

NOTICE

DO NOT set low--heat manifold pressure less than 1.3--in. w.c.
(324 Pa) or more than 1.7 in. w.c. (423 Pa) for natural gas. If
required manifold pressure is outside this range, change main
burner orifices to obtain manifold pressure in this range.

i. Install low-- heat regulator adjustment cap.

62

j. Move setup switch SW1--2 to OFF position after complet-

ing low--heat adjustment.

k. Leave manometer or similar device connected and proceed

to Step 2.

2. Adjust manifold pressure to obtain high fire input rate See
Fig. 33.

a. Jumper R to W/W1 and W2 thermostat connections on fur-

nace control. This keeps furnace locked in high --heat oper­ation.

b. Remove regulator adjustment cap from high--heat gas

valve pressure regulator and turn high heat adjusting screw
(3/16--in.or smaller flat-- tipped screwdriver) counterclock­wise (out) to decrease input rate or clockwise (in) to in­crease input rate. See Fig. 33.

NOTICE

DO NOT set high--heat manifold pressure less than 3.2--in.
w.c. (797 Pa) or more than 3.8 in. w.c. (947 Pa) for natural
gas. If required manifold pressure is outside this range,
change main burner orifices to obtain manifold pressure in this
range.

e of Step 1 untilcorrect low--heat input is achieved. Re--in­stall low heat regulator seal cap on gas valve.

i. Jumper R to W/W1, and W2. This keeps furnace locked

in high-- heat operation when both W/W1 and W2 are ener­gized.

j. Repeat items d through g for high--heat operation, repeat-

ing Step 2 and adjusting the high--heat regulator screw as
required.

2. Restore furnace to normal operating condition.

a. Turn gas valve ON/OFF switch to OFF.

b. Remove water column manometer or similar device from

manifold pressure tap.

!

WARNING

FIRE HAZARD

Failure to follow this warning could result in personal
injury, death, and/or property damage.

Manifold pressure tap set screw must be tightened or 1/8--in.
NPT pipe plug must be installed to prevent gas leaks.

c. When correct input is obtained, replace caps that conceal

gas valve regulator adjustment screws. Main burner flame
should be clear blue, almost transparent See Fig. 62.

d. Remove jumpers R to W/W1 and R to W2.

Burner Flame

Burner

Manifold

A89020

Fig. 62 -- Burner Flame

Clocking the Meter

1. Verify natural gas input rate by clocking meter.

NOTE: Contact your HVAC distributor or gas supplier for metric
gas meter tables, if required.

a. Turn off all other gas appliances and pilots served by the

meter.

b. Move setup switch SW1--2 toON position. This keepsfur-

nace locked in low--heat operation when only W/W1 is en­ergized..

c. Jumper R to W/W1.

d. Run furnace for 3 minutes in low--heat operation.

e. Measure time (in sec) for gas meter tocomplete one revolu-

tion and note reading. The 2 or 5 cubic feet dial provides
a more accurate measurement of gas flow.

f. Refer to Table 20 for cubic ft. of gas per hr.

g. Multiply gas rate cu ft./hr by heating value (Btuh/cu ft.) to

obtain input rate.

h. If clocked rate does not match required input from Step 1,

increase manifold pressure to increase input or decrease
manifold pressure to decrease input.Repeat steps b through

c. Tighten set screw on manifold pressure tap with 3/32--in.

hex wrench,or if⅛--in. NPTplug wasremoved,applypipe
dope sparingly to end of plug and re--install in the gas
valve.

d. Turn gas valve ON/OFF switch to ON.

e. Move setup SW1--2 on furnace control to position required

for attached thermostat (OFF for single-stage thermostats,
ON for two-stage thermostats).

f. Check for gas leaks and verify furnace operation.

Adjust T emperature Rise

NOTE: Blower door must be installed when taking temperature

rise reading. Leaving blower door off will result in incorrect
temperature measurements, due to possible changes in duct static
pressure and airflow.

!

CAUTION

FURNACE DAMAGE HAZARD

Failure to follow this caution may result in:
S Overheating the heat exchangers or condensing flue gases
in heat exchanger areas not designed for condensate.

S Shortened furnace life

S Component damage.

Temperature rise must be within limits specified on furnace
rating plate. Recommended operation is at midpoint of rise
range or slightly above.

When setup switch SW1--4 is ON, operation will be near the high
end of the rise range for improved comfort.

Determine air temperature rise as follows:

1. Place thermometers in return and supply ducts as near
furnace as possible. Be sure thermometers do not see heat
exchanger so that radiant heat does not affect readings. This
practice is particularly important with straight--run ducts.

2. When thermometer readings stabilize, subtract return--air
temperature from supply--air temperature to determine air
temperature rise.

NOTE: Temperature rise can be determined for low--heat and
high--heat operation by locking the furnace in each mode of

63

operation. The mode of operation is based on the position of Setup
Switch SW1--2 on the furnace control board.

3. This furnace is capable of automatically providing proper
airflow to maintain the temperature rise within the range
specified on furnace rating plate. If temperature rise is
outside this range, proceed as follows:

a. Check gas input for low-- and high--heat operation.

b. Check derate for altitude, if applicable.

c. Check all return andsupply ducts for excessive restrictions

causing static pressure greater than 0.5--In. W.C.

d. Ensure Comfort/Efficiency SW1--4 on furnace control is

in OFF=Efficiency position when a bypass humidifier is
used. See Fig. 40 for switch location.

e. Verify correct model plug is installed.

To lock the furnace in low heat:

1. Turn SW1--2 ON at the furnace control.

2. Connect a jumper across R and W/W1 at the thermostat
terminals at the furnace control.

3. Allow the burners to ignite and the blower to turn on.

4. Allow the supply temperature to stabilize and verify the
proper rise range.

If the temperature rise is too high or too low in low heat:

1. Remove jumpers from R and W/W1.

2. Wait until the blower off delay is completed.

3. Turn 115 VAC power off.

4. Check the position of setup switch SW1--4. When set to
OFF, airflow is raised 7% for low heat Factory default
position is ON.

5. Turn 115 VAC power on.

6. Re--check low heat temperature rise.

To lock the furnace in high heat:

1. Connect a jumper across R and W/W1 and W2 at the
thermostat terminals at the furnace control.

2. Allow the burners to ignite and the blower to turn on.

3. Allow the supply temperature to stabilize and verify the
proper rise range.

If the temperature rise is too high or too low in high heat:

1. Remove jumpers from R and W/W1 and W2.

2. Wait until the blower off delay is completed.

3. Turn 115 VAC power off.

4. Check the position of setup switch SW1--4. When set to
OFF, airflow is raised 7% for low Heat, and 10% for high
heat. Factory default position is ON.

5. Turn 115 VAC power on.

6. Re--check high heat temperature rise.

After the temperature rise has been verified:

1. Remove jumpers from thermostat terminals.

2. Allow the blower off delay to complete.

3. Turn setup switches SW1--2 to the OFF position unless
two--stage thermostat operation is desired. See Fig. 65.

4. Proceed to “Adjust Blower Off Delay” or install blower
door if complete.

Adjust Blower Off Delay (Heat Mode)

1. Remove blower door if installed.

2. Turn Dip switch SW--7 or SW--8 ON or OFF for desired
blower off delay. See Table 19 and Fig. 40, 65 and 73.

Adjust Cooling Airflow – High-Speed and
Low-Speed

The ECM blower can be adjusted for a range of airflows for
low-speed or high-speed cooling. See Table 9 – Air Delivery –
CFM (With Filter) and Fig. 65 – Furnace Setup Switches and

Cooling

Descriptions. Depending on the model size, the cooling airflow
can be adjusted from 1.5 to 6 tons based on 350 CFM per ton.

NOTE: 6 ton airflow will truncate at 2200 CFM on applicable
models.

The high-speed or single-speed cooling airflow is adjusted by
turning Setup switches SW2--6, SW2--7 and SW2--8 either ON or
OFF. Select the required airflow from Table 9. Table 9 is based
upon 350 CFM per ton. For other CFM per ton Setup switch
selections, see Fig. 40, 65 and 73.

The Continuous Fan airflow selection via Setup switches SW2 is
also the airflow for low-speed cooling when the furnace is used
with a 2-speed cooling or heat pump unit. Adjust SW2--3, 4, 5 to
match the airflow required for low-speed cooling. Select the
required airflow from Table 9 and Fig. 65.

NOTE: The airflow selected via SW2-- 3, 4, 5 (Low-Speed
Cooling Airflow) cannot exceed the airflow selected via SW2--6, 7,
8 (High-Speed Cooling Airflow). For other CFM per ton Setup
switch selections, see Fig. 40 and 65.

NOTE: The airflow settings for SW2--6, 7, 8 and SW2 --3, 4, 5
selections are the same, EXCEPT for the default values. See Table

9.

For a complete explanation of cooling airflow, refer to the section
titled “Sequence of Operation.”

Adjust Continuous Fan Airflow (and Low-Speed
Cooling

Adjust continuous fan and low--stage cooling airflow using
SW2--3, 4, 5 and refer to Fig. 65. The continuous fan speed can be
further adjusted at a conventional thermostat using the continuous
fan speed select function. Changing the continuous fan speed at a
conventional thermostat DOES NOT change the low-speed
cooling airflow selected via SW2 at the control board.

Refer to the section titled “Continuous Blower Speed Selection for
Thermostat.”

Airflow)

Adjust Thermostat Heat Anticipator.

1. Mechanical thermostat. Set thermostat heat anticipator to
match the amp. draw of the electrical components in the
R-- W/W1 circuit. Accurate amp. draw readings can be
obtained at the wires normally connected to thermostat
subbase terminals, R and W. The thermostat anticipator
should NOT be in the circuit while measuring current.

THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
(ANITICIPATOR, CLOCK, ETC.,
MUST BE OUT OF CIRCUIT.)

HOOK-AROUND
AMMETER

R Y W G

10 TURNS

FROM UNIT 24-V
CONTROL TERMINALS

EXAMPLE:

5.0 AMPS ON AMMETER
10 TURNS AROUND JAWS

Fig. 63 -- Amp. Draw Check with Ammeter

a. Set SW1--2 switch on furnace control board to ON.

64

0.5 AMPS FOR THERMOSTAT

=

ANTICIPATOR SETTING

A96316

b. Remove thermostat from subbase or from wall.

c. Connect an amp. meter as shown in Fig. 63 across the R

and W subbase terminals or R and W wires at wall.

d. Record amp. draw across terminals when furnace is in low

heat and after blower starts.

e. Set heat anticipator on thermostat per thermostat

instructions and install on subbase or wall.

f. Turn SW1--2 switch OFF.

g. Install blower door.

2. Electronic thermostat: Set cycle rate for 3 cycles per hr.

Check Safety Controls

The flame sensor, gas valve, and pressure switch were all checked
in the Start-- up procedure section as part of normal operation.

1. Check Main Limit Switch
This control shuts off combustion system and energizes air-­circulating blower motor, if furnace overheats. By using this
method to check limit control, it can be established that lim­it is functioning properly and will operate if there is a re­stricted return--air supply or motor failure. If limit control
does not function during this test, cause must be determined
and corrected.

a. Run furnace for at least 5 minutes.

b. Gradually block off return air with a piece of cardboard or

sheet metal until the limit trips.

c. Unblock return air to permit normal circulation.

d. Burners will re--light when furnace cools down.

2. Check Pressure Switch(es)
This control proves operation of the draft inducer blower.

a. Turn off 115--v power to furnace.

b. Disconnect inducer motor lead wires from wire harness.

c. Turn on 115 --v power to furnace.

d. Set thermostat to “call for heat” and wait 1 minute. When

pressure switch is functioning properly, hot surface igniter
should NOT glow and control diagnostic light flashes a
status code 32. If hot surface igniter glows when inducer
motor is disconnected, shut down furnace immediately.

e. Determine reason pressure switch did not function proper-

ly and correct condition.

f. Turn off 115--v power to furnace.

g. Reconnect inducer motor wires, replace door, and turn on

115--v power.

h. Blower will run for 90 sec beforebeginningthecallforheat

again.

i. Furnace should ignite normally.

Checklist

1. Put away tools and instruments. Clean up debris.

2. Verify that switches SW1--1 and SW1 --6 are OFF and other
setup switches are set as desired. Verify that switches
SW1--7 and SW1-- 8 for the blower OFF DELAY are set as
desired per Table 19.

3. Verify that blower and control doors are properly installed.

4. Verify that there are no unsealed openings in the blower
shelf or casing.

5. Cycle test furnace with room thermostat.

6. Check operation of accessories per manufacturer’s instruc­tions.

7. Review Owner’s Manual with owner.

8. Attach literature packet to furnace.

65

Fig. 64 -- Service Label Information

66

A190070

Fig. 65 -- Furnace Setup Switch Description

A190048

1. Default A/C airflow when
A/C setup switches are in
OFF position.

2 . D e f a u lt L o w --- S t a g e A / C

airflow when CF switches
are in OFF position

Fig. 66 -- Airflow Selection (based on 350 CFM/TON) for A/C (SW2--6, 7, 8) and *CF (SW2--3, 4, 5)

67

A190148

Table 18 – Altitude Derate Multiplier for USA

ALTITUDE

FT. M

0–2000 0 --- 6 1 0 0 1.00
2001–3000 610 --- 914 4 --- 6 0.95
3001–4000 914--- 1219 6 --- 8 0.93
4001–5000 1219--- 1524 8 --- 1 0 0.91
5001–6000 1524--- 1829 10 --- 12 0.89
6001–7000 1829--- 2134 12 --- 14 0.87
7001–8000 2134 ---2438 14--- 16 0.85
8001–9000 2438 ---2743 16--- 18 0.83

9001–10,000 2743---3048 18---20 0.81

*Derate multiplier factors are based on midpoint altitude for al titude range.

PERCENT

OF

DERATE

DERATE

MULTIPLIER

FACTOR*

Table 20 – Gas Rate (CU ft./hr)

SECONDS

FOR 1 REVOLUTION

10 360 720 1800 50 72 144 360
11 327 655 1636 51 71 141 355
12 300 600 1500 52 69 138 346
13 277 555 1385 53 68 136 340
14 257 514 1286 54 67 133 333
15 240 480 1200 55 65 131 327
16 225 450 1125 56 64 129 321
17 212 424 1059 57 63 126 316
18 200 400 1000 58 62 124 310
19 189 379 947 59 61 122 305
20 180 360 900 60 60 120 300
21 171 343 857 62 58 116 290
22 164 327 818 64 56 112 281
23 157 313 783 66 54 109 273
24 150 300 750 68 53 106 265
25 144 288 720 70 51 103 257
26 138 277 692 72 50 100 250
27 133 267 667 74 48 97 243
28 129 257 643 76 47 95 237
29 124 248 621 78 46 92 231
30 120 240 600 80 45 90 225
31 116 232 581 82 44 88 220
32 113 225 563 84 43 86 214
33 109 218 545 86 42 84 209
34 106 212 529 88 41 82 205
35 103 206 514 90 40 80 200
36 100 200 500 92 39 78 196
37 97 195 486 94 38 76 192
38 95 189 474 96 38 75 188
39 92 185 462 98 37 74 184
40 90 180 450 100 36 72 180
41 88 176 439 102 35 71 178
42 86 172 429 104 35 69 173
43 84 167 419 106 34 68 170
44 82 164 409 108 33 67 167
45 80 160 400 110 33 65 164
46 78 157 391 112 32 64 161
47 76 153 383 116 31 62 155
48 75 150 375 120 30 60 150
49 73 147 367

1CuFt. 2CuFt. 5CuFt. 1CuFt. 2CuFt. 5CuFt.

SIZE OF TEST DIAL

Table 1 9 – Blower Off Delay Setup Switch

DESIRED HEATING MODE

BLOWER OFF DELAY (SEC.)

90 OFF OFF
120 ON OFF
150 OFF ON
180 ON ON

SECONDS

FOR 1 REVOLUTION

SETUP SWITCH

( S W 1 --- 7 A N D --- 8 )

POSITION

S W 1 --- 7 S W 1 --- 8

SIZE OF TEST DIAL

68

Table 21 – Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate

TWO-STAGE FURNACE

(TABULATED DATA BASED ON 20,000 BTUH HIGH-HEAT / 13,000 BT UH LOW-HEAT PER BURNER,

DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)

ALTITUDE

RANGE

ft (m)

092543 3.6 / 1.5 43 3.7 / 1.6 43 3.8 / 1.6 42 3.2 / 1.4

(0) 950 43 3.4 / 1.4 43 3.5 / 1.5 43 3.6 / 1.5 43 3.7 / 1.6

to 1000 44 3.5 / 1.5 44 3.6 / 1.5 44 3.8 / 1.6 43 3.4 / 1.4

U.S.A. and CanadaU.S.A. On

y U.S.A. Only U.S.A. and Canada

l

U.S.A. On

ly

ly

U.S.A. On

2000 1050 44 3.2 / 1.3 44 3.3 / 1.4 44 3.4 / 1.4 44 3.5 / 1.5

(610) 1075 45 3.7 / 1.6 45 3.8 / 1.6 44 3.3 / 1.4 44 3.4 / 1.4

U.S.A. 800 42 3.4 / 1.4 42 3.5 / 1.5 42 3.6 / 1.5 42 3.7 / 1.6

2001 (611) 825 43 3.8 / 1.6 42 3.3 / 1.4 42 3.4 / 1.4 42 3.5 / 1.5

to 850 43 3.6 / 1.5 43 3.7 / 1.6 42 3.2 / 1.3 42 3.3 / 1.4

3000 (914) 875 43 3.4 / 1.4 43 3.5 / 1.5 43 3.7 / 1.5 43 3.8 / 1.6

Canada 925 44 3.5 / 1.5 44 3.6 / 1.5 44 3.8 / 1.6 43 3.4 / 1.4

2001 (611) 950 44 3.3 / 1.4 44 3.4 / 1.5 44 3.6 / 1.5 44 3.7 / 1.6

to 975 44 3.2 / 1.3 44 3.3 / 1.4 44 3.4 / 1.4 44 3.5 / 1.5

4500 (1372) 1000 46 3.8 / 1.6 45 3.8 / 1.6 44 3.2 / 1.4 44 3.3 / 1.4

3001 800 43 3.8 / 1.6 42 3.2 / 1.4 42 3.3 / 1.4 42 3.4 / 1.4

(915) 825 43 3.6 / 1.5 43 3.7 / 1.6 43 3.8 / 1.6 42 3.2 / 1.4

to

4000 900 44 3.4 / 1.4 44 3.5 / 1.5 44 3.7 / 1.5 44 3.8 / 1.6

(1219) 925 44 3.2 / 1.4 44 3.4 / 1.4 44 3.5 / 1.5 44 3.6 / 1.5

4001 775 43 3.7 / 1.6 43 3.8 / 1.6 42 3.3 / 1.4 42 3.4 / 1.4

(1220) 800 43 3.5 / 1.5 43 3.6 / 1.5 43 3.7 / 1.6 43 3.8 / 1.6

to

5000 875 44 3.3 / 1.4 44 3.5 / 1.5 44 3.6 / 1.5 44 3.7 / 1.6

(1524) 900 44 3.2 / 1.3 44 3.3 / 1.4 44 3.4 / 1.4 44 3.5 / 1.5

5001 750 43 3.7 / 1.5 43 3.8 / 1.6 42 3.2 / 1.4 42 3.3 / 1.4

(1525) 775 43 3.4 / 1.4 43 3.5 / 1.5 43 3.7 / 1.5 43 3.8 / 1.6

to

6000 850 44 3.3 / 1.4 44 3.4 / 1.4 44 3.5 / 1.5 44 3.6 / 1.5

(1829) 875 45 3.7 / 1.6 44 3.2 / 1.3 44 3.3 / 1.4 44 3.4 / 1.4

6001 700 42 3.2 / 1.3 42 3.3 / 1.4 42 3.4 / 1.4 42 3.5 / 1.5

(1830) 725 43 3.6 / 1.5 43 3.7 / 1.6 43 3.8 / 1.6 42 3.3 / 1.4

to

7000 800 44 3.4 / 1.4 44 3.5 / 1.5 44 3.6 / 1.5 44 3.7 / 1.6

(2133) 825 44 3.2 / 1.3 44 3.3 / 1.4 44 3.4 / 1.4 44 3.5 / 1.5

HEATVALUE0.580.600.620.64

AT ALTITUDE Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press

(Btu/cu ft) No. High/Low No. High/Low No. High/Low No. High/Low

900 43 3.8 / 1.6 42 3.2 / 1.4 42 3.3 / 1.4 42 3.4 / 1.4

975 44 3.7 / 1.6 44 3.8 / 1.6 43 3.4 / 1.5 43 3.6 / 1.5

1025 44 3.3 / 1.4 44 3.5 / 1.5 44 3.6 / 1.5 44 3.7 / 1.6

1100 46 3.7 / 1.6 46 3.8 / 1.6 45 3.8 / 1.6 44 3.2 / 1.4

900 44 3.7 / 1.6 44 3.8 / 1.6 43 3.5 / 1.5 43 3.6 / 1.5

775 42 3.3 / 1.4 42 3.4 / 1.4 42 3.5 / 1.5 42 3.6 / 1.5

850 44 3.8 / 1.6 43 3.5 / 1.5 43 3.6 / 1.5 43 3.7 / 1.6

875 44 3.6 / 1.5 44 3.7 / 1.6 43 3.4 / 1.4 43 3.5 / 1.5

950 45 3.7 / 1.6 44 3.2 / 1.3 44 3.3 / 1.4 44 3.4 / 1.4

750 42 3.3 / 1.4 42 3.4 / 1.4 42 3.5 / 1.5 42 3.6 / 1.5

825 44 3.8 / 1.6 43 3.4 / 1.4 43 3.5 / 1.5 43 3.6 / 1.5

850 44 3.5 / 1.5 44 3.7 / 1.5 44 3.8 / 1.6 43 3.4 / 1.4

925 46 3.8 / 1.6 45 3.7 / 1.6 44 3.2 / 1.4 44 3.3 / 1.4

725 42 3.2 / 1.4 42 3.3 / 1.4 42 3.4 / 1.5 42 3.5 / 1.5

800 44 3.7 / 1.6 44 3.8 / 1.6 43 3.4 / 1.5 43 3.5 / 1.5

825 44 3.5 / 1.5 44 3.6 / 1.5 44 3.7 / 1.6 44 3.8 / 1.6

900 46 3.7 / 1.6 46 3.8 / 1.6 45 3.8 / 1.6 44 3.2 / 1.4

675 42 3.4 / 1.4 42 3.5 / 1.5 42 3.6 / 1.5 42 3.8 / 1.6

750 43 3.4 / 1.4 43 3.5 / 1.5 43 3.6 / 1.5 43 3.7 / 1.6

775 44 3.6 / 1.5 44 3.7 / 1.6 43 3.4 / 1.4 43 3.5 / 1.5

850 46 3.8 / 1.6 45 3.8 / 1.6 44 3.2 / 1.4 44 3.3 / 1.4

SAGLARUTANFOYTIVARGCIFICEPSSAG.GVA

A11252A

69

Table 21 -- Orifice Size and Manifold Pressure (In. W.C.) for Gas Input Rate (Continued)

TWO-STAGE FURNACE

(TABULATED DATA BASED ON 20,000 BTUH HIGH-HEAT / 13,000 BT UH LOW-HEAT PER BURNER,

DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)

ALTITUDE

RANGE

ft (m)

7001 675 43 3.8 / 1.6 42 3.2 / 1.4 42 3.3 / 1.4 42 3.4 / 1.5

(2134) 700 43 3.5 / 1.5 43 3.7 / 1.5 43 3.8 / 1.6 42 3.2 / 1.4

to

8000 775 44 3.3 / 1.4 44 3.4 / 1.4 44 3.5 / 1.5 44 3.7 / 1.5

(2438) 800 45 3.8 / 1.6 44 3.2 / 1.4 44 3.3 / 1.4 44 3.4 / 1.4

8001 650 43 3.8 / 1.6 42 3.2 / 1.4 42 3.3 / 1.4 42 3.4 / 1.4

(2439) 675 43 3.5 / 1.5 43 3.6 / 1.5 43 3.7 / 1.6 42 3.2 / 1.3

to

U.S.A. OnlyU.S.A. Only U.S.A. Only

* Orifice numbers shown in BOLD are factory-installed.

9000 750 44 3.3 / 1.4 44 3.4 / 1.4 44 3.5 / 1.5 44 3.6 / 1.5

(2743) 775 45 3.7 / 1.6 44 3.2 / 1.3 44 3.3 / 1.4 44 3.4 / 1.4

9001 600 42 3.3 / 1.4 42 3.4 / 1.5 42 3.6 / 1.5 42 3.7 / 1.6

(2744) 625 43 3.7 / 1.6 42 3.2 / 1.3 42 3.3 / 1.4 42 3.4 / 1.4

to

10000 700 44 3.4 / 1.4 44 3.5 / 1.5 44 3.7 / 1.5 44 3.8 / 1.6

(3048) 725 44 3.2 / 1.3 44 3.3 / 1.4 44 3.4 / 1.4 44 3.5 / 1.5

HEATVALUE0.580.600.620.64

AT ALTITUDE Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press Orifice Mnfld Press

(Btu/cu ft) No. High/Low No. High/Low No. High/Low No. High/Low

650 42 3.4 / 1.4 42 3.5 / 1.5 42 3.6 / 1.5 42 3.7 / 1.6

725 44 3.8 / 1.6 43 3.4 / 1.4 43 3.5 / 1.5 43 3.6 / 1.5

750 44 3.5 / 1.5 44 3.7 / 1.5 44 3.8 / 1.6 43 3.4 / 1.4

825 46 3.7 / 1.6 46 3.8 / 1.6 45 3.8 / 1.6 44 3.2 / 1.4

625 42 3.4 / 1.4 42 3.5 / 1.5 42 3.6 / 1.5 42 3.7 / 1.6

700 44 3.7 / 1.6 43 3.4 / 1.4 43 3.5 / 1.5 43 3.6 / 1.5

725 44 3.5 / 1.5 44 3.6 / 1.5 44 3.7 / 1.6 44 3.8 / 1.6

650 43 3.5 / 1.5 43 3.6 / 1.5 43 3.7 / 1.6 43 3.8 / 1.6

675 44 3.7 / 1.6 44 3.8 / 1.6 43 3.4 / 1.4 43 3.5 / 1.5

SERVICE AND MAINTENANCE

PROCEDURES

Untrained personnel can perform basic maintenance functions such
as cleaning and replacing air filters. All other operations must be
performed by trained service personnel. A qualified service person
should inspect the furnace once a year.

!

WARNING

FIRE, INJURY OR DEATH HAZARD

Failure to follow this warning could result in personal
injury, death and/or property damage.

The ability to properly perform maintenance on this
equipment requires certain knowledge, mechanical skills,
tools, and equipment. If you do not possess these, do not
attempt to perform any service and maintenance on this
equipment other than those procedures recommended in the
Owner’s Manual.

!

CAUTION

ENVIRONMENTAL HAZARD

Failure to follow this caution may result in environmental
pollution.

Remove and recycle all components or materials (i.e. oil,
refrigerant, control board, etc.) before unit final disposal.

SAGLARUTANFOYTIVARGCIFICEPSSAG.GVA

A11252B

!

WARNING

ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD

Failure to follow this warning could result in personal
injury or death, or property damage.

Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag. There may be more than one
disconnect switch. Lock out and tag switch with a suitable
warning label. Verify proper operation after servicing.
Always reinstall access doors after completing service and
maintenance.

!

CAUTION

ELECTRICAL OPERATION HAZARD

Failure to follow this caution may result in improper
furnace operation or failure of furnace.

Label all wires prior to disconnection when servicing
controls. Wiring errors can cause improper and dangerous
operation.

General

These instructions are written as if the furnace is installed in an
upflow application. An upflow furnace application is where the
blower is located below the combustion and controls section of the
furnace, and conditioned air is discharged upward. Since this
furnace can be installed in any of the 4 positions shown in Fig. 3,

70

you must revise your orientation to component location
accordingly.

Electrical Controls and Wiring

Each pressure switch is labeled with the reference location (noted
as “COLLECTOR BOX --LPS” or “HOUSING--HPS” on the
switch). The nominal break point of each switch is shown on the
label below the reference location in inches of water column,
“W.C.” The maximum and minimum break point of the switch is
+/-- 0.05 inches of water column from the nominal break point of
the switch. The maximum make point of the switch is 0.10 inches
of water above the maximum break point of the switch.

Example: Nominal break point on pressure switch is 0.68--in.
W.C. The minimum break point of the switch is 0.63--in. W.C.
The maximum break point of the switch is 0.73--in. W.C. The
maximum make point of the switch is 0.83 --in. W.C.

!

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury
or death.

There may be more than one electrical supply to the furnace.
Check accessories and cooling unit for additional electrical
supplies that must be shut off during furnace servicing. Lock
out and tag switch with a suitable warning label.

The electrical ground and polarity for 115--v wiring must be
properly maintained. Refer to Fig. 39 for field wiring information
and to Fig. 73 for furnace wiring information.

NOTE: If the polarity is not correct, the STATUS LED on the
control will flash rapidly and prevent the furnace from heating. The
control system also requires an earth ground for proper operation
of the control and flame--sensing electrode.

The 24--v circuit contains an automotive--type, 3--amp. fuse located
on the control. See Fig. 40. Any shorts of the 24--v wiring during
installation, service, or maintenance will cause this fuse to blow. If
fuse replacement is required, use ONLY a 3--amp. fuse. The control
LED will display display status code 24 when fuse needs to be
replaced.

Troubleshooting

Refer to the service label. See Fig. 64.

The Troubleshooting Guide can be a useful tool in isolating
furnace operation problems. Beginning with the word “Start,”
answer each question and follow the appropriate arrow to the next
item. See Fig. 72.

The Guide will help to identify the problem or failed component.
After replacing any component, verify correct operation sequence.

Proper instrumentation is required to service electrical controls.
The control in this furnace is equipped with a Status Code LED
(Light--Emitting Diode) to aid in installation, servicing, and
troubleshooting. Status codes can be viewed at the indicator in
blower door. The amber furnace control LED is either ON
continuously, rapid flashing, or a code composed of 2 digits. The
first digit is the number of short flashes, the second digit is the
number of long flashes.

For an explanation of status codes, refer to service label located on
blower door or Fig. 64, and the troubleshooting guide which can
be obtained from your distributor.

Retrieving Stored Status Codes

The stored status codes will NOT be erased from the control
memory, when 115-- or 24--v power is interrupted. The control will
store up to the last 7 Status Codes in order of occurrence.

1. To retrieve status codes, proceed with the following:

NOTE: NO thermostat signal may be present at control, and all
blower--OFF delays must be completed.

a. Leave 115--v power to furnace turned on.

b. Look into blower door indicator for current LED status.

c. Remove blower door.

NOTE: The Status Codes cannot be retrieved by disconnecting
the limit switch. To retrieve Status Codes, follow the procedure
below.

2. Turn Setup Switch, SW1 --1 “ON.”

3. Manually close blower door switch.

4. Control will flash up to 7 Status Codes.

5. The last Status Code, or 8th Code, will be Code 11.

6. Turn SW1--1 “OFF.”

7. Amber LED will be ON continuous which indicates proper
operation.

8. Release blower door switch, install blower door and refer
to the SERVICE label on the blower door for more informa­tion.

Component Self--Test

Component Test can ONLY be initiated by performing the
following:

1. Remove blower door.

2. Remove the wire from the “R” terminal of the control
board.

3. Turn Setup Switch, SW--1--6 “ON.”

4. Manually close blower door switch.

Blower door switch opens 115-- v power to control. No component
operation can occur unless switch is closed. Caution must be taken
when manually closing this switch for service purposes.

!

WARNING

ELECTRICAL SHOCK HAZARD

Failure to follow this warning could result in personal injury,
or death.

Blower door switch opens 115-- v power to furnace control.
No component operation can occur unless switch is closed.
Exercise caution to avoid electrical shock from exposed
electrical components when manually closing this switch for
service purposes.

5. Component Test sequence will function as follows:

a. The furnace control CPU turns the inducer motor ON at

high--heat speed and keeps it ON through step c.

b. After waiting 10 seconds the furnace control CPU turns the

hot surface igniter ON for 15 seconds, then OFF.

c. The furnace control CPU then turns the blower motor

BLWM on at mid--range airflow for 15 seconds, then OFF.

d. After shutting the blower motor OFF the furnace control

CPU switches the inducer to low--heat speed for 10 sec­onds, then OFF.

NOTE: The EAC terminals are energized when the blower is
operating.
After the component test is completed, 1 or more status codes (11,
or 25) will flash. See component test section or Service Label (Fig.

64) for explanation of status codes.

NOTE: To repeat component test, turn setup switch SW1--6 to
OFF and then back ON.

e. TurnsetupswitchSW1--6OFF.

6. RELEASE BLOWER DOOR SWITCH, reattach wire to
“R” terminal on furnace control board and replace blower
door.

71

Care and Maintenance

!

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal
injury, death and/or property damage.

Never store flammable or combustible materials on, near, or
in contact with the furnace, such as:

1. Spray or aerosol cans, rags, brooms, dust mops,
vacuum cleaners, or other cleaning tools.

2. Soap powders, bleaches, waxes or other cleaning
compounds, plastic or plastic containers, gasoline,
kerosene, cigarette lighter fluid, dry cleaning fluids,
or other volatile fluids.

3. Paint thinners and other painting compounds, paper
bags, or other paper products. Exposure to these
materials could lead to corrosion of the heat
exchangers.

For continuing high performance and to minimize possible furnace
failure, periodic maintenance must be performed on this furnace.
Consult your local dealer about proper frequency of maintenance
and the availability of a maintenance contract.

!

WARNING

4. Inspect burner compartment before each heating season for
rust, corrosion, soot or excessive dust. If necessary, have
furnace and burner serviced by a qualified service agency.

5. Inspect the vent pipe/vent system before each heating sea­son for water leakage, sagging pipes or broken fittings.
Have vent pipes/vent system serviced by a qualified service
agency.

6. Inspect any accessories attached to the furnace such as a hu­midifier or electronic air cleaner. Perform any service or
maintenance to the accessories as recommended in the ac­cessory instructions.

Cleaning and/or Replacing Air Filter

The air filter type may vary depending on the application or
orientation. The filter is external to the furnace casing. There are no
provisions for an internal filter with this furnace. See “Filter
Arrangement” under the “Installation” section of this manual.

!

WARNING

CARBON MONOXIDE POISONING AND FIRE
HAZARD

Failure to follow this warning could result in personal
injury, death and/or property damage.

Never operate furnace without a filter or filtration device
installed. Never operate a furnace with filter or filtration
device access doors removed.

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury,
death, and/or property damage.

Turn off the gas and electrical supplies to the furnace and
install lockout tag before performing any maintenance or
service. Follow the operating instructions on the label
attached to the furnace.

!

WARNING

CARBON MONOXIDE POISONING AND FIRE
HAZARD

Failure to follow this warning could result in personal
injury, death and/or property damage.

Never operate furnace without a filter or filtration device
installed. Never operate a furnace with filter or filtration
device access doors removed.

!

CAUTION

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care
and wear appropriate protective clothing, safety glasses and
gloves when handling parts, and servicing furnaces.

The minimum maintenance on this furnace is as follows:

1. Check and clean air filter each month or more frequently if
required. Replace if torn.

2. Check blower motor and wheel for cleanliness each heating
and cooling season. Clean as necessary.

3. Check electrical connections for tightness and controls for
proper operation each heating season. Service as necessary.

NOTE: If the filter has an airflow direction arrow, the arrow must
point toward the blower.
To clean or replace filters, proceed as follows:

!

WARNING

ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD

Failure to follow this warning could result in personal
injury or death, or property damage.

Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag. There may be more than one
disconnect switch. Lock out and tag switch with a suitable
warning label. Verify proper operation after servicing.
Always reinstall access doors after completing service and
maintenance.

1. Turn off electrical supply to furnace.

2. Remove filter cabinet door.

3. Slide filter out of cabinet.

4. If equipped with permanent, washable filter, clean filter by
spraying cold tap water through filter in opposite direction
of airflow. Rinse filter and let dry. Oiling or coating of the
filter is not recommended.

5. If equipped with factory specified disposable media filter,
replace only with a factory specified media filter of the same
size.

6. Slide filter into cabinet.

7. Replace filter cabinet door.

8. Turn on electrical supply to furnace.

Blower Motor and Wheel Maintenance

To ensure long life, economy, and high efficiency, clean
accumulated dirt and grease from blower wheel and motor
annually.

72

The inducer and blower motors are pre--lubricated and require no
additional lubrication. These motors can be identified by the
absence of oil ports on each end of the motor.

The following items should be performed by a qualified service
technician. Clean blower motor and wheel as follows:

1. Turn off electrical supply to furnace.

2. Remove blower door.

3. All factory wires can be left connected, but field thermostat
and accessory wiring may need to be disconnected depend­ing on their length and routing.

4. If the vent and combustion air pipe passes through the
blower compartment, it will be necessary to remove the
pipes from the blower compartment.

Disconnect the vent and combustion air pipe by:

a. Loosen the clamps on the vent couplings and combustion

air pipe external to the furnace.

b. Separate the pipes from the couplings and move them

aside.

c. Loosen the clamps on the vent couplings and combustion

air pipe located on the blower shelf.

d. Separate the pipes from the blower compartment and set

aside.

e. Remove the couplingsfromthe pipe adapters and set aside.

f. After servicing the blower, reverse steps a through e.

g. Tighten all clamps 15 lb -- in.

See Fig. 67 For Steps 5 through 14.

MOTOR SHAFT FLAT

SET SCREW

MOTOR WHEEL HUB

GROMMET

MOTOR ARM

SCREW

Representative drawing of DIBC blower wheel only,

some models may va ry in ap peara nce.

Fig. 67 -- Blower Assembly

A190094

SEE DETAIL

A

SCREW LOCATION

BLOWER HSG ASSY

BRACKET

BRACKET
ENGAGEMENT

DETAIL

A

CUTOFF, BLOWER

WHEEL, BLOWER

BRACKET

CAPACITOR
OR POWER CHOKE
(WHEN USED)

Representative drawing only, some models may vary in appearance.

SCREW

(GND)

BLOWER HSG ASSY

MOTOR, BLOWER

A11584

5. Remove screws securing blower assembly to blower shelf
and slide blower assembly out of furnace. Detach ground
wire and disconnect blower motor harness plugs from blow­er motor.

NOTE: Blower wheel is fragile. Use care.

6. Clean blower wheel and motor by using a vacuum with soft
brush attachment. Be careful not to disturb balance weights
(clips) on blower wheel vanes. Do not bend wheel or blades
as balance will be affected.

7. If greasy residue is present on blower wheel, remove wheel
from the blower housing and wash it with an appropriate
degreaser. To remove wheel:

NOTE: The DIBC composite wheel used in some models should
be cleaned with mild soapy water only. Allow wheel to dry prior to
reassembly.

a. Mark blower wheel location on shaft before disassembly

to ensure proper reassembly.

b. Loosen setscrew holding blower wheel on motor shaft.

NOTE: Mark blower mounting arms and blower housing so each
arm is positioned at the same hole location during reassembly.

c. Mark blower wheel orientation and cutoff plate location to

ensure proper reassembly.

d. Remove screws securing cutoff plate and remove cutoff

plate from housing.

e. Remove bolts holding motor mounts to blower housing

and slide motor and mounts out of housing.

f. Remove blower wheel from housing.

g. Clean wheel per instructions on degreaser cleaner. Do not

get degreaser in motor.

8. Reassemble motor and blower wheel by reversing items 7b
through 7f. Ensure wheel is positioned for proper rotation.

73

9. Torque motor mounting bolts to 40 +/-- 10 lb--in.. when re­assembling.

10. Torque blower wheel set screw to 160 +/-- 20 lb--in.. when
reassembling.

11. Verify that blower wheel is centered in blower housing and
set screw contacts the flat portion of the motor shaft. Loosen
set screw on blower wheel and reposition if necessary.

12. Spin the blower wheel by hand to verify that the wheel does
not rub on the housing.

13. Reinstall blower assembly in furnace.

14. Reinstall 2 screws securing blower assembly to blower
deck.

15. Reconnect blower leads to furnace control. Refer to furnace
wiring diagram, and connect thermostat leads if previously
disconnected.

NOTE: Be sure to attach ground wire and reconnect blower
harness plugs to blower motor.

!

WARNING

!

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury,
death, and/or property damage.

Turn off the gas and electrical supplies to the furnace and
install lockout tag before performing any maintenance or
service. Follow the operating instructions on the label
attached to the furnace.

BURNER SUPT. ASSY

BURNER ASSY

IGNITER

BRACKET, IGNITER

ELECTRICAL OPERATION HAZARD

Failure to follow this warning could result in personal injury
or death.

Blower door switch opens 115--v power to control. No
component operation can occur unless switch is closed.
Caution must be taken when manually closing this switch for
service purposes.

16. Downflow or horizontal furnaces with vent pipe through
furnace only:

a. Install and connect short piece of vent pipe inside furnace

to existing vent.

b. Connect vent connector to vent elbow.

17. Turn on electrical supply. Manually close blower door
switch. Use a piece of tape to hold switch closed. Check for
proper rotation and speed changes between heating and
cooling by jumpering R to G and R to Y/Y2 on furnace
control thermostat terminals. If outdoor temperature is be­low 70_F, turn off circuit breaker to outdoor unit before
running furnace in the cooling cycle. Turn outdoor circuit
breaker on after completing cooling cycle. See Fig. 40.

NOTE: If R--W/W1 thermostat terminals are jumpered at the time
blower door switch is closed, blower will run for 90 sec before
beginning a heating cycle.

a. Perform component self--testas shown at the bottomof the

SERVICE label, located on the blower door.

b. Verify blower is rotating in the correct direction

18. If furnace is operating properly, RELEASE BLOWER
DOOR SWITCH. Remove any jumpers or reconnect any
disconnected thermostat leads. Replace blower door.

19. Turn on gas supply and cycle furnace through one complete
heating cycle. Verify the furnace temperature rise as shown
in Adjustments Section. Adjust temperature rise as shown in
Adjustments Section.

Cleaning Burners and Flame Sensor

The following items must be performed by a qualified service
technician. If the burners develop an accumulation of light dirt or
dust, they may be cleaned by using the following procedure:

NOTE: Use a back-up wrench on the gas valve to prevent the
valve from rotating on the manifold or damaging the mounting to
the burner assembly.

Refer to Fig. 68.

FLAME ROLLOUT
SWITCH

FLAME SENSOR
(BELOW BURNER)

A11403

Fig. 68 -- Burner Assembly

1. Disconnect power at external disconnect, fuse or circuit
breaker.

2. Turn off gas at external shut-off or gas meter.

3. Remove control door and set aside.

4. Turn electric switch on gas valve to OFF.

5. Disconnect the gas pipe from gas valve and remove pipe
from the furnace casing.

6. Remove individual wires from terminals on gas valve.

7. Disconnect Hot Surface Igniter (HSI) wires from HSI.

8. Disconnect Flame Sensor wire from Flame Sensor.

9. Support the manifold and remove the 4 screws that secure
the manifold assembly to the burner assembly and set aside.
Note the location of the green/yellow wire and ground ter­minal.

10. Inspect the orifices in the manifold assembly for blockages
or obstructions. Remove orifice and clean or replace orifice.

11. Remove the four screws that attach the top plate of the cas­ing to the furnace.

12. Raise top plate up slightly and prop it up with a small piece
of wood or folded cardboard.

13. Support the burner assembly and remove the screws that at­tach the burner assembly to the heat exchanger cell panel.

14. Remove wires from both rollout switches.

15. Slide one-- piece burner out of slots on sides of burner as­sembly.

16. Remove the flame sensor from the burner assembly.

17. (Optional) Remove the Hot Surface Igniter (HSI) and
bracket from the burner assembly.

18. Check igniter resistance. Nominal resistance is 40 to 70
ohms at room temperature and is stable over the life of the
igniter.

19. Clean burner with a brush and a vacuum.

20. Clean the flame sensor with fine steel wool (0000 grade).
Do not use sand paper or emery cloth.

74

To reinstall burner assembly:

1. Install the Hot Surface Igniter (HSI) and bracket in burner
assembly.

2. Install flame sensor on burner.

3. Align the edges of the one-piece burner with the slots in the
burner assembly and slide the burners forward until they are
fully seated in the burner assembly.

4. Align the orifices in the manifold assembly with the support
rings on the end of the burner.

5. Insert the orifices in the support rings of the burners.

NOTE: If manifold does not fit flush against the burner, do not
force the manifold on the burner assembly. The burners are not
fully seated forward in the burner assembly. Remove the manifold
and check burner positioning in the burner assembly assembly
before re-installing the manifold.

6. Attach the green/yellow wire and ground terminal to one of
the manifold mounting screws.

7. Install the remaining manifold mounting screws.

8. Check the igniter alignment. See Fig. 69, 70 and 68.

9. Attach the wires to the roll-out switches.

10. Align the burner assembly with the openings in the primary
cell inlet panel and attach the burner assembly to the cell
panel.

11. Connect the wire for the flame sensor.

12. Connect the wire for the Hot Surface Igniter.

NOTE: Use propane-resistant pipe dope to prevent leaks. Do not
use PTFE thread--seal tape.

13. Install the gas pipe to the gas valve.

!

WARNING

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury
death, and/or property damage.

Never purge a gas line into a combustion chamber. Never test
for gas leaks with an open flame. Use a commercially available
soap solution made specifically for the detection of leaks to
check all connections. A fire or explosion may result causing
property damage, personal injury or loss of life.

14. Check for gas leaks with a commercially available soap so­lution made specifically for the detection of leaks.

15. Turn gas on at electric switch on gas valve and at external
shut-off or meter

16. Turn power on at external disconnect, fuse or circuit break­er.

17. Run the furnace through two complete heating cycles to
check for proper operation

18. Install control door when complete.

2ïin.

50 mm

3/8ïin.

9.6 mm

3/16ïin.

4.6 mm

+ 1/32

1/10ïin.

ï 1/16ïin.

+0.8

2.5 mm
ï1.5 mm

L12F041

Fig. 70 -- Igniter Position -- Side View

Servicing Hot Surface Igniter

The igniter does NOT require annual inspection. Check igniter
resistance before removal. Refer to Fig. 69, 70 and 68.

1. Turn off gas and electrical supplies to furnace.

2. Remove control door.

3. Disconnect igniter wire connection.

4. Check igniter resistance. Igniter resistance is affected by
temperature. Only check resistance when the igniter is at
room temperature.

a. Using an ohm meter, check resistance across both igniter

leads in connector.

b. Cold reading should be between 40 ohms and 70 ohms.

5. Remove igniter assembly.

a. Using a 1/4--in. driver, removethe twoscrews securing the

igniter mounting bracket to the burner assembly See Fig.
68 .

b. Carefully withdraw the igniter and bracket assembly

through the front of the burner assembly without striking
the igniter on surrounding parts.

c. Inspect igniter for signs of damage or failure.

d. If replacement is required, remove the screw that secures

the igniter on igniter bracket and remove the igniter.

6. To replace igniter and bracket assembly, reverse items 5a
through 5d.

7. Reconnect igniter harness to the igniter, dressing the igniter
wires to ensure there is no tension on the igniter itself. See
Fig. 68.

8. Turn on gas and electrical supplies to furnace.

9. Verify igniter operation by initiating control board self--test
feature or by cycling thermostat.

10. Replace control door.

Flushing Collector Box and Drainage System

1-1/4-in.

(31.8)

2-1/2-in.

(64.4)

Fig. 69 -- Igniter Position -- Top View

A11405

!

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury,
death, and/or property damage.

Turn off the gas and electrical supplies to the furnace and
install lockout tag before performing any maintenance or
service. Follow the operating instructions on the label
attached to the furnace.

1. Turn off gas and electrical supplies to furnace.

75

2. Remove control door.

3. Disconnect pressure switch tube from pressure switch port.

NOTE: Ensure the pressure switch tube disconnected from the
pressure switch is higher than the collector box opening or water
will flow out of tube.

4. Remove the collector box plug from the top port on the up­per corner of the collector box. See Fig. 60.

5. Attach a funnel with a flexible tube to port on the collector
box.

6. Flush inside of collector box with water until discharge wa­ter from condensate trap is clean and runs freely.

7. Repeat steps 4 thru 6 with bottom plug on upper corner of
collector box.

8. Remove the pressure switch tube from the collector box.

NOTE:DoNOT blow into tube with tube connected to the
pressure switch.

9. Clean pressure switch port on collect box with a small wire.
Shake any water out of pressure switch tube.

10. Reconnect tube to pressure switch and pressure switch port.

11. Remove the relief tube from the port on the collector box
and the trap.

12. Clean the relief port on collect box and the trap with a small
wire. Shake any water out of the tube.

13. Reconnect relief tube to trap and collector box ports.

Cleaning Condensate Drain and Trap

NOTE: If the condensate trap is removed, a new gasket between

the trap and collector box is required. Verify a condensate trap
gasket is included in the service kit or obtain one from your local
distributor.

1. Disconnect power at external disconnect, fuse or circuit
breaker.

2. Turn off gas at external shut-off or gas meter.

3. Remove control door and set aside.

4. Turn electric switch on gas valve to OFF.

5. Disconnect external drain from condensate drain elbow or
drain extension pipe inside the furnace and set aside.

6. Disconnect the condensate trap relief hose from collector
box port and condensate trap.

NOTE: If condensate has a heat pad attached to the trap, trace the
wires for the pad back to the connection point and disconnect the
wires for the heat pad.

7. Remove the screw that secures the condensate trap to the
collector box, remove the trap and set aside.

8. Remove the trap gasket from the collector box if it did not
come off when the trap was removed.

9. Discard the old trap gasket.

10. Rinse condensate trap in warm water until trap is clean.

11. Flush condensate drain lines with warm water. Remember
to check and clean the relief port on the collector box.

12. Shake trap dry.

13. Clean port on collector box with a small wire.

To re-install Condensate Drain and Trap:

1. Remove adhesive backing from condensate trap gasket

2. Install gasket on collector box

3. Align the condensate trap with the drain opening on the col­lector box and secure the trap with the screw

4. Attach the relief hose to the relief port on the condensate
trap and collector box.

5. Secure tubing to prevent any sags or traps in the tubing.

6. Connect condensate drain elbow or drain extension elbow
to the condensate trap

7. Connect the leads of the condensate heat pad (if used)

8. Connect external drain piping to the condensate drain elbow
or drain extension pipe.

9. Turn gas on at electric switch on gas valve and at external
shut-off or meter

10. Turn power on at external disconnect, fuse or circuit break­er.

11. Run the furnace through two complete heating cycles to
check for proper operation

12. Install control door when complete.

Checking Heat Pad Operation (If Applicable)

In applications where the ambient temperature around the furnace
is 32_F or lower, freeze protection measures are required. If this
application is where heat tape has been applied, check to ensure it
will operate when low temperatures are present.

NOTE: The Heat Pad, when used, should be wrapped around the
condensate drain trap. There is no need to use heat tape within the
furnace casing. Most heat tapes are temperature activated, and it is
not practical to verify the actual heating of the tape. Check the
following:

1. Check for signs of physical damage to heat tape such as
nicks, cuts, abrasions, gnawing by animals, etc.

2. Check for discolored heat tape insulation. If any damage or
discolored insulation is evident, replace heat tape.

3. Check that heat tape power supply circuit is on.

Cleaning Heat Exchangers

The following items must be performed by a qualified service
technician.

Primary Heat Exchangers

If the heat exchangers get an accumulation of light dirt or dust on
the inside, they may be cleaned by the following procedure:

NOTE: If the heat exchangers get a heavy accumulation of soot
and carbon, both the primary and secondary heat exchangers
should be replaced rather than trying to clean them thoroughly due
to their intricate design. A build--up of soot and carbon indicates
that a problem exists which needs to be corrected, such as improper
adjustment of manifold pressure, insufficient or poor quality
combustion air, improper vent termination, incorrect size or
damaged manifold orifice(s), improper gas, or a restricted heat
exchanger (primary or secondary). Action must be taken to correct
the problem.

1. Turn off gas and electrical supplies to furnace.

!

WARNING

ELECTRICAL SHOCK, FIRE OR EXPLOSION
HAZARD

Failure to follow this warning could result in personal
injury or death, or property damage.

Before installing, modifying, or servicing system, main
electrical disconnect switch must be in the OFF position and
install a lockout tag. There may be more than one
disconnect switch. Lock out and tag switch with a suitable
warning label. Verify proper operation after servicing.
Always reinstall access doors after completing service and
maintenance.

76

!

WARNING

!

WARNING

ELECTRICAL SHOCK AND FIRE HAZARD

Failure to follow this warning could result in personal injury,
death, and/or property damage.

Turn off the gas and electrical supplies to the furnace and
install lockout tag before performing any maintenance or
service. Follow the operating instructions on the label
attached to the furnace.

A11273

Fig. 71 -- Cleaning Heat Exchanger Cell

2. Remove control door.

3. Disconnect wires or connectors to flame rollout switch, gas
valve, igniter, and flame sensor.

4. Using backup wrench, disconnect gas supply pipe from fur­nace gas control valve.

5. Remove two screws attaching top filler plate and rotate up­wards to gain access to screws attaching burner assembly to
cell panel.

6. Remove screws attaching burner assembly to cell panel.
See Fig. 68.

NOTE: Burner cover, manifold, gas valve, and burner assembly
should be removed as one assembly.

7. Clean heat exchanger openings with a vacuum and a soft
brush. See Fig. 71.

NOTE: After cleaning, inspect the heat exchangers to ensure they
are free of all foreign objects that may restrict flow of combustion
products.

8. Reverse items 6 through 1 for reassembly.

9. Refer to furnace wiring diagram and reconnect wires to
flame rollout switch, gas valve, igniter, and flame sensor.

10. Turn on gas and electrical supplies to furnace.

11. Check furnace operation through 2 complete heat operating
cycles. Look at burners. Burner flames should be clear blue,
almost transparent. See Fig. 62.

12. Check for gas leaks.

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in personal injury
death, and/or property damage.

Never purge a gas line into a combustion chamber. Never test
for gas leaks with an open flame. Use a commercially available
soap solution made specifically for the detection of leaks to
check all connections. A fire or explosion may result causing
property damage, personal injury or loss of life.

13. Replace main furnace door.

Secondary Heat Exchangers

The condensing side (inside) of the secondary heat exchanger
CANNOT be serviced or inspected without complete removal of
the heat exchanger assembly. Detailed information on heat
exchanger removal can be obtained from your Distributor.

Wiring Diagrams

See Fig. 73 for the Deluxe 4--Way Multipoise Furnace wiring
diagrams.

WINTERIZA TION

!

CAUTION

UNIT AND PROPERTY DAMAGE HAZARD

Failure to follow this caution may result in unit component or
property damage.

If the furnace is installed in an unconditioned space where the
ambient temperatures may be 32_ F(0_ C) or lower, freeze
protection measures must be taken to prevent minor property
or product damage.

Since the furnace uses a condensing heat exchanger, some water
will accumulate in the unit as a result of the heat transfer process.
Therefore, once it has been operated, it cannot be turned off and
left off for an extended period of time when temperatures will
reach 32_F(0_C) or lower unless winterized. Follow these
procedures to winterize your furnace:

!

CAUTION

UNIT COMPONENT DAMAGE HAZARD

Failure to follow this caution may result in damage to the
furnace and other property damage.

Do not use ethylene glycol (automotive antifreeze coolant or
equivalent). Failure of plastic components may occur.

1. Obtain propylene glycol (RV/swimming pool antifreeze or
equivalent).

2. Turn off gas and electrical supplies to your furnace.

3. Remove furnace control door.

4. Remove the top unused rubber plug from the port on the
collector box opposite the condensate trap. See Fig. 60.

5. Connect a field supplied 3/8--in. (9.5--mm) ID tube to the
open port on the collector box

6. Insert a field supplied funnel into the tube.

7. Pour 1 quart of anti--freeze solution into the funnel/tube.
Antifreeze should run through the inducer housing, overfill
condensate trap and flow to an open drain.

8. Replace the rubber plug in the port on the collector box.

9. Remove the middle unused rubber plug from the port on the
collector box opposite the condensate trap. See Fig. 60.

77

10. Repeat Steps 5 through 8.

11. If a condensate pump is used, check with pump
manufacturer to verify pump is safe for use with antifreeze
used. Allow pump to start and pump anti--freeze to open
drain.

12. Replace main door.

13. When furnace is re--started, flush condensate pump with
clear water to check for proper operation before re--starting
furnace.

14. Propylene glycol need not be removed before re-- starting
furnace.

SEQUENCE OF OPERATION

NOTE: Furnace control must be grounded for proper operation or

else control will lock out. Control is grounded through
green/yellow wire routed to gas valve and burner box screw. Using
the schematic diagram in Fig. 73, follow the sequence of operation
through the different modes. Read and follow the wiring diagram
very carefully.

NOTE: If a power interruption occurs during a call for heat
(W/W1 or W/W1--and-- W2), the control will start a 90-- second
blower--only ON period two seconds after power is restored, if the
thermostat is still calling for gas heating. The rAmber LED light
will flash code 12 during the 90--second period, after which the
LED will be ON continuous, as long as no faults are detected.
After the 90-- second period, the furnace will respond to the
thermostat normally.

The blower door must be installed for power to be conducted
through the blower door interlock switch ILK to the furnace
control CPU, transformer TRAN, inducer motor IDM, blower
motor BLWM, hot--surface igniter HSI, and gas valve GV.

1. Two--Stage Heating (Adaptive Mode) with Single--Stage

Thermostat

See Fig. 40 and 41 for thermostat connections

NOTE: The low--heat only switch SW1--2 selects either the
low--heat only operation mode when ON, (see item 2. below) or
the adaptive heating mode when OFF in response to a call for heat.
See Fig. 65. When the W2 thermostat terminal is energized it will
always cause high--heat operation when the R--to--W circuit is
closed, regardless of the setting of the low--heat only switch. This
furnace can operate as a two--stage furnace with a single--stage
thermostat because the furnace control CPU includes a
programmed adaptive sequence of controlled operation, which
selects low--heat or high--heat operation. This selection is based
upon the stored history of the length of previous gas--heating
periods of the single--stage thermostat.

The furnace will start up in either low-- or high--heat. If the furnace
starts up in low-- heat, the control CPU determines the low-- heat
on--time (from 0 to 16 minutes) which is permitted before
switching to high --heat.

If the power is interrupted, the stored history is erased and the
control CPU will select low--heat for up to 16 minutes and then
switch to high--heat, as long as the thermostat continues to call for
heat. Subsequent selection is based on stored history of the
thermostat cycle times.

The wall thermostat “calls for heat”, closing the R--to--W circuit.
The furnace control performs a self--check, verifies the low--heat
and high--heat pressure switch contacts LPS and HPS are open, and
starts the inducer motor IDM in high--speed.

a. Inducer Prepurge Period

(1.) If the furnace control CPU selects low--heat opera-

tion the inducer motor IDM comes up to speed, the
low--heat pressure switch LPS closes, and the fur­nace control CPU begins a 15-- second prepurge
period. If the low--heat pressure switch LPS fails to
remain closed the inducer motor IDM will remain

running at high--speed. After the low-- heat pressure
switch re--closes the furnace control CPU will be­gin a 15-- second prepurge period, and continue to
run the inducer motor IDM at high--speed.

(2.) If the furnace control CPU selects high--heat opera-

tion, the inducer motor IDM remains running at
high--speed, and the high--heat pressure switch re­lay HPSR is de-- energized to close the NC contact.
When sufficient pressure is available the high--heat
pressure switch HPS closes, and the high--heat gas
valve solenoid GV--HI is energized. The furnace
control CPU begins a 15-- second prepurge period
after the low--heat pressure switch LPS closes. If
the high--heat pressure switch HPS fails to close
and the low--heat pressure switch LPS closes, the
furnace will operate at low-- heat gas flow rate until
the high--heat pressure switch closes for a maxi­mum of 2 minutes after ignition.

b. Igniter Warm--Up --At the end of the prepurge period,the

Hot--Surface Igniter HSI is energized for a 17-- second ig­niter warm--up period.

c. Trial--For--Ignition Sequence --When the igniter warm--

up period is completed the main gas valve relay contact
GVR closes to energize the gas valve solenoid GV--M. The
gas valve solenoid GV--M permits gas flow to the burners
where it is ignited by the HSI. Five seconds after the GVR
closes, a 2--second flame proving period begins. The HSI
igniter will remain energized until the flame is sensed or
until the 2--second flame proving period begins. If the fur­nace control CPU selects high--heat operation, the high-­heat gas valve solenoid GV--HI is also energized.

d. Flame--Proving -- When the burner flame is proved at the

flame--proving sensor electrode FSE, the inducer motor
IDM switches to low--speed unless the furnace is operating
inhigh--heat,and the furnacecontrol CPU beginsthe blow­er--ON delay period and continues to hold the gas valve
GV--M open. If the burner flame is not proved within two
seconds, the control CPU will close the gas valve GV--M,
and the control CPU will repeat the ignition sequence for
up to three more Trials-- For--Ignition before going to Igni­tion--Lockout. Lockout will be reset automatically after
threehours, orby momentarily interrupting 115 vacpower
to the furnace, or by interrupting 24 vac power at SEC1 or
SEC2 tothe furnacecontrolCPU (not at W/W1, G, R,etc.).
If flame is proved when flame should not be present, the
furnace control CPU will lock out of Gas--Heating mode
and operate the inducer motor IDM on high speed until
flame is no longer proved.

e. Blower--On delay -- Ifthe burnerflame is proven the blow-

er--ON delays for low--heat and high--heat are as follows:

Low--heat

openedthe blower motor BLWM is turned ON at low--heat
airflow.
High--heat -- 25 seconds after the gas valve GV--M is
opened the BLWM is turned ON at high--heat airflow. Si­multaneously, the humidifierterminal HUM andelectronic
air cleaner terminal EAC--1 are energized and remain ener­gized throughout the heating cycle.

f. SwitchingfromLow-- to High--Heat -- If the furnacecon-

trolCPU switches from low--heat to high--heat, the furnace
control CPU will switch the inducer motor IDM speed
from low to high. The h igh--heat pressure switch relayHP­SR is de--energized to close the NC contact. When suffi­cient pressure is available the high--heat pressure switch
HPS closes, and the high--heat gas valve solenoid GV--HI
is energized. The blower motor BLWM will transition to

-- 45 seconds after the gas valve GV-- M is

78

high--heat airflow five seconds after the furnace control
CPU switches from low--heat to high--heat.

g. Switching from High-- to Low-- Heat --The furnace con-

trol CPU will not switch from high--heat to low--heat while
the thermostat R-- to--W circuit is closed when using a sin­gle--stage thermostat.

h. Blower--Off Delay --When the thermostat is satisfied, the

R to W circuitis opened, de--energizing the gas valve GV -­M, stopping gas flow to the burners, and de--energizing the
humidifier terminal HUM. The inducer motor IDM will re­main energized for a 15--second post--purge period. The
blower motor BLWM and air cleaner terminal EAC-- 1 will
remain energized at low--heat airflow or transition to low-­heat airflow for 90, 120, 150, or 180 seconds (depending
on selection at blower--OFF delay switches). The furnace
control CPU is factory --set for a 120--second blower-- OFF
delay.

2. Two--Stage Thermostat and Two--Stage Heating
See Fig. 40 and 41 for thermostat connections.

NOTE: In this mode the low--heat only switch SW1-- 2 must be
ON to select the low--heat only operation mode in response to
closing the thermostat R--to--W1 circuit. Closing the thermostat
R--to-- W1--and--W2 circuits always causes high--heat operation,
regardless of the setting of the low--heat only switch.

The wall thermostat “calls for heat”, closing the R--to-- W1 circuit
for low--heat or closing the R--to--W1--and--W2 circuits for
high--heat. The furnace control performs a self-- check, verifies the
low--heat and high --heat pressure switch contacts LPS and HPS are
open, and starts the inducer motor IDM in high--speed.

The start up and shut down functions and delays described in item

1. above apply to the 2 --stage heating mode as well, except for
switching from low-- to high--Heat and vice versa.

a. Switching from Low-- to High-- Heat -- If the thermostat

R--to--W1 circuit is closed and the R--to--W2 circuit closes,
the furnace control CPU will switch the inducer motor
IDM speed from low to high. The high--heat pressure
switch relay HPSR is de--energized to close the NC contact.
When sufficient pressure is available the high-- heat pres­sure switch HPS closes, and the high-- heat gas valve sole­noid GV--HI is energized. The blower motor BLWM will
transition to high--heat airflow five seconds after the
R--to--W2 circuit closes.

b. Switching from High-- to Low-- Heat --If the thermostat

R--to-- W2 circuit opens, and theR--to --W1 circuit remains
closed, the furnace control CPU will switch the inducer
motor IDM speed from high to low. The high -- heat pres­sure switch relay HPSR is energized to open the NC contact
and de--energize the high--heat gasvalve solenoid GV -- HI.
When the inducer motor IDM reduces pressure sufficient­ly, the high--heat pressure switch HPS will open. The gas
valvesolenoid GV-- M will remain energized aslong as the
low--heat pressure switch LPS remains closed. The blower
motor BLWM will transition to low--heat airflow five sec­onds after the R-- to -- W2 circuit opens.

3. Cooling mode
The thermostat “calls for cooling”.

a. Single--Speed Cooling--

See Fig. 40 and 41 for thermostat connections
The thermostat closes the R--to--G--and--Y circuits. The
R--to-- Y circuit starts the outdoor unit, and the R--to-­G--and-- Y/Y2 circuits start the furnace blower motor
BLWM on cooling airflow. Cooling airflow is based on the
A/C selection shown in Fig. 65. The electronic air cleaner
terminal EAC--1 is energized with 115 vac when the blow­er motor BLWM is operating.
When the thermostat is satisfied, the R--to--G-- and--Y cir­cuits are opened. The outdoor unit will stop, and the fur-

nace blower motor BLWM will continue operating at cool­ing airflow for an additional 90 seconds. Jumper Y/Y2 to
DHUM to reduce the cooling off--delay to 5 seconds. See
Fig. 40.

b. Single--Stage Thermostat and Two--Speed Cooling

(Adaptive Mode) -­See Fig. 40 and 41 for thermostat connections.
This furnace can operate a two --speed cooling unit with a
single--stage thermostat because the furnace control CPU
includes a programmed adaptive sequence of controlled
operation, which selects low--cooling or high-- cooling op­eration. This selection is based upon the stored history of
the length of previous cooling period of the single--stage
thermostat.

NOTE: The air conditioning relay disable jumper ACRDJ must
be connected to enable the adaptive cooling mode in response to a
call for cooling. See Fig. 40. When ACRDJ is in place the furnace
control CPU can turn on the air conditioning relay ACR to
energize the Y/Y2 terminal and switch the outdoor unit to
high--cooling.
The furnace control CPU can start up the cooling unit in either
low-- or high--cooling. If starting up in low--cooling, the furnace
control CPU determines the low--cooling on--time (from 0 to 20
minutes) which is permitted before switching to high--cooling. If
the power is interrupted, the stored history is erased and the furnace
control CPU will select low--cooling for up to 20 minutes and then
energize the air conditioning relay ACR to energize the Y/Y2
terminal and switch the outdoor unit to high--cooling, as long as
the thermostat continues to call for cooling. Subsequent selection is
based on stored history of the thermostat cycle times.
The wall thermostat “calls for cooling”, closing the
R--to-- G --and--Y circuits. The R-- to--Y1 circuit starts the outdoor
unit on low--cooling speed, and the R--to--G--and-- Y1 circuits starts
the furnace blower motor BLWM at low--cooling airflow which is
the true on--board CF selection as shown in Fig. 65.
If the furnace control CPU switches from low--cooling to
high--cooling, the furnace control CPU will energize the air
conditioning relay ACR. When the air conditioning relay ACR is
energized the R--to--Y1--and--Y2 circuits switch the outdoor unit to
high--cooling speed, and the R--to--G--and--Y1--and--Y/Y2 circuits
transition the furnace blower motor BLWM to high--cooling
airflow. High--cooling airflow is based on the A/C selection shown
in Fig. 40.

NOTE: When transitioning from low-- cooling to high--cooling the
outdoor unit compressor will shut down for 1 minute while the
furnace blower motor BLWM transitions to run at high--cooling
airflow.
The electronic air cleaner terminal EAC-- 1 is energized with 115
vac whenever the blower motor BLWM is operating.
When the thermostat is satisfied, the R--to--G--and--Y circuit are
opened. The outdoor unit stops, and the furnace blower BLWM
and electronic air cleaner terminal EAC-- 1 will remain energized
for an additional 90 seconds. Jumper Y1 to DHUM to reduce the
cooling off--delay to 5 seconds. See Fig. 40.

c. Two-- Stage Thermostat and Two--Speed Cooling

See Fig. 40 and 41 for thermostat connections

NOTE: The air conditioning relay disable jumper ACRDJ must
be disconnected to allow thermostat control of the outdoor unit
staging. See Fig. 40.

The thermostat closes the R--to--G--and--Y1 circuits for
low--cooling or closes the R--to--G--and--Y1--and--Y2 circuits for
high--cooling. The R--to--Y1 circuit starts the outdoor unit on
low--cooling speed, and the R--to --G--and--Y1 circuit starts the
furnace blower motor BLWM at low--cooling airflow which is the
true on--board CF (continuous fan) selection as shown in Fig. 69.
The R--to--Y1 --and--Y2 circuits start the outdoor unit on

79

high--cooling speed, and the R--to-- G--and -- Y/Y2 circuits start the
furnace blower motor BLWM at high--cooling airflow.
High--cooling airflow is based on the A/C (air conditioning)
selectionshowninFig.65.
The electronic air cleaner terminal EAC-- 1 is energized with 115
vac whenever the blower motor BLWM is operating.
When the thermostat is satisfied, the R--to--G--and-- Y1 or R--to-­G--and-- Y1 --and--Y2 circuits are opened. The outdoor unit stops,
and the furnace blower BLWM and electronic air cleaner terminal
EAC--1 will remain energized for an additional 90 seconds. Jumper
Y1 to DHUM to reduce the cooling off--delay to 5 seconds. See
Fig. 40.

4. Dehumidification Mode
See Fig. 40 and 41 for thermostat connections.
The dehumidification output, D or DHUM on the Ther­midistat should be connected to the furnace control thermo­stat terminal DHUM. When there is a dehumidify demand,
the DHUM input is activated, which means 24 vac signal is
removed from the DHUM input terminal. In other words,
the DHUM input logic is reversed. The DHUM input is
turned ON when no dehumidify demand exists. Once 24
vac is detected by the furnace control on the DHUM input,
dehumidification capability is activated. If the DHUM input
is removed for more than 48 hours, the furnace control re­verts back to non --dehumidification mode.
The cooling operation described in item 3 above also ap­plies to operation with a dehumidification thermostat . The
exceptions are listed below:

a. Low cooling-- W h e n t h e R -- t o -- G -- a n d -- Y 1 c i r c u i t i s c l o s e d

and there is a demand for dehumidification, the low cool­ing airflow demand is reduced by 10 percent.

b. High cooling-- W h e n t h e R -- t o -- G -- a n d Y / Y 2 c i r c u i t i s

closed and there is a demand for dehumidification, high
cooling airflow demand is reduced by 10 percent.

c. Cooling off--delay-- When the “call for cooling” is satisfied

and there is a demand for dehumidification, the cooling
blower--off delay is decreased from 90 seconds to 5 sec­onds.

5. Continuous Blower Mode
When the R--to --G circuit is closed by the thermostat, the
blower motor BLWM will operate at continuous blower air­flow. Continuous blower airflow selection is initially based
on the CF (continuous fan) selection shown in Fig. 65. Fac­tory default is shown in Fig. 65. Terminal EAC --1 is ener­gized as long as the blower motor BLWM is energized.
During a call for heat, the furnace control CPU will transi­tion the blower motor BLWM to continuous blower airflow
or low--heat airflow whichever is lowest. The blower motor
BLWM will remain ON until the main burners ignite then
shut OFF and remain OFF for the blower--ON delay (45
seconds in low--heat, and 25 seconds in high-- heat), allow­ing the furnace heat exchangers to heat up more quickly,
then restarts at the end of the blower--ON delay period at
low--heat or high--heat airflow, respectively.
The blower motor BLWM will revert to continuous--blower
airflow after the heating cycle is completed. In high-- heat,
the furnace control CPU will drop the blower motor BLWM
to low--heat airflow during the selected blower--OFF delay
period before transitioning to continuous--blower airflow.
When the thermostat “calls for low--cooling”, the blower
motor BLWM will switch to operate at low-- cooling airflow.

When the thermostat is satisfied, the blower motor BLWM
will operate an additional 90 seconds at low-- cooling air­flow before transitioning back to continuous--blower air­flow.
When the thermostat “calls for high--cooling”, the blower
motor BLWM will operate at high cooling airflow. When
the thermostat is satisfied, the blower motor BLWM will op­erate an additional 90 seconds at high--cooling airflow be­fore transitioning back to continuous--blower airflow. When
the R-- to--G circuit is opened, the blower motor BLWM will
continue operating for an additional 5 seconds, if no other
function requires blower motor BLWM operation.

Continuous Blower Speed Selection from Thermostat To
select different continuous-- blower airflow from the room
thermostat, momentarily turn off the FAN switch or push
button on the room thermostat for 1--3 seconds after the
blower motor BLWM is operating. The furnace control
CPU will shift the continuous--blower airflow from the
factory setting to the next highest CF selection airflow as
shown in Fig. 65. Momentarily turning off the FAN switch
again at the thermostat will shift the continuous-- blower
airflow up one more increment. If you repeat this procedure
enough you will eventually shift the continuous--blower
airflow to the lowest CF selection as shown in Fig. 65. The
selection can be changed as many times as desired and is
stored in the memory to be automatically used following a
power interruption.

NOTE: If the blower-- off delay is set to the maximum, the
adjustable continuous--fan feature is locked (i.e., fan speed cannot
be changed from its current setting).

6. Heat pump
See Fig. 40 and 41 for thermostat connections.
When installed with a heat pump, the furnace control auto­matically changes the timing sequence to avoid long blower
off times during demand defrost cycles. Whenever W/W1 is
energized along with Y1 or Y/Y2, the furnace control CPU
will transition to or bring on the blower motor BLWM at
cooling airflow or low--heat airflow whichever is lowest.
The blower motor BLWM will remain on until the main
burners ignite then shut OFF and remain OFF for 25 sec­onds before coming back on at heating airflow. When the
W/W1 input signal disappears, the furnace control begins a
normal inducer post--purge period while changing the blow­er airflow. If Y/Y2 input is still energized the furnace con­trol CPU will transition the blower motor BLWM airflow to
cooling airflow. If Y/Y2 input signal disappears and the Y1
input is still energized the furnace control CPU will transi­tion the blower motor BLWM to low--cooling airflow. If
both the Y1 and Y/Y2 signals disappear at the same time,
the blower motor BLWM will remain on at low-- heat air­flow for the selected blower--OFF delay period. At the end
of the blower-- OFF delay, the blower motor BLWM will
shut OFF unless G is still energized, in which case the blow­er motor BLWM will operate at continuous blower airflow.

7. Component self--test
The furnace features a component test system to help diag­nose a system problem in the case of a component failure.
To initiate the component test procedure, ensure that there
are no thermostat inputs to the control and all time delays
have expired. Turn on setup switch SW1--6. See Fig. 40.)
Refer to Page 71 for instructions.

80

NO

g

SEYSEYSEY

NO

YES

NO

Guide

Troubleshootin

NO

Is door switch closed?

Is door switch closed?

Is circuit breaker closed?

NO

YES

Is there 115V going to switch?

NO

Check for continuity in wire from circuit

breaker to furnace.

Close circuit breaker a nd go back to

START.

Is 24V present at W /W1, W2, Y1, Y/Y2 or

G thermostat terminals on the furnace

Check room thermostat or

interconnecting cable.

control?

Disconnect all the thermostat wires from

the furnace control.

Does the problem repeat when using a

jumper wire?

The thermostat is not c ompatible with the

furnace control. Eithe r install a ballast

resistor, connect the Com24V thermostat

terminal to the thermostat, or replace the

thermostat.

YES

YES

Replace door switch.

Replace transformer.

Does the control respond to W/W1, W2,

Y1, Y/Y2, and G (24V) thermostat

signals?

Run system through a lo w-heat, high-

heat, or cooling cycle to c heck operation.

Status codes are erased after 72 hours

or can be manually erased by putting

setup switch SW1-1 in the ON posi tion

and jumpering R, W /W1, and Y/Y2

simultaneously until status code #11 is

flashed.

Replace furnace control.

ONON

YES

Is the re 115V at L1 and L 2?

ONON

Is there 24V at SEC-1 and SEC-2?

YES

Replace furnace control.

Check for correct line volt age polarity. If

units are twinned, check for proper low-

voltage (24V) transformer phasing.

YES

NO

To recall previous status codes disconnect the R

NO

thermostat connection, res et power, and put setup

switch SW1-1 in the ON position. The AMBER LED

will flash the status codes in the order of occurrence.

Record status codes until status code #11 flashes (1

short and 1 long flash). After status c ode #11

flashes the status codes will repeat. Status codes

are erased after 72 hours or can be manually erased

by putting setup switch SW1-1 in the ON position

and jumpering R, W/W1, and Y/Y2 simultaneously

until status code #11 is flas hed. When don e put

setup switch SW1-1 in the O FF position.

Was there a previous status code other

than #11?

YES

and prove flame in 4 attem pts. Control will aut o-reset

after 72 hours or can be manually erased by putting

setupswitchSW1-1intheONposition andjumpering

R, W/W1, and Y/Y2 simultaneo usly until status code

#11 is flashed. Run system through a low-heat, hi gh-

heat, or cooling cycle t o check system.

– Normal operation. Blower runs for 90 seconds, if

unit is powered up during a call for heat (R-W/W1

closed) or when (R-W/W 1 opens) during the blower

on-delay period.

limit or flame rollout switch is open longer than 3

minutes or 10 successive limit trips occurred during

high-heat. Cont rol will auto-reset after 3 hours. See

code 33.

11 NO PREV IOUS CODE – Status codes are erased

12 BLOWER ON AFTER POWER UP – (115V OR 24V)

13 L IMIT CIRCUIT LOCKOUT – Lockout occurs if the

after 3 hours. See status code 34.

14 IGN ITION LOCKOUT – System failed to ignite gas

YES

START

Is AMBER LED status light on?

Is AMBER LED status light blinking

rapidly without a paus e?

Is AMBER LED status light blinking

ON/OFF slowly with a combination of

short and long flashes?

Determine status code. The status code

is a 2 digit number with the first digit

determined by the number of short

flashes and the second digit by the

number of long flashes ?

Go to section below for the status code

that was flashed.

A113325A

Fig. 72 -- Troubleshooting Guide

81

Troubleshooting Guide (Continued)

82

A190262

Fig. 73 -- Wiring Diagram

83

344605--- 2 REV C

A190259

PARTS REPLACEMENT INFORMATION GUIDE

Casing Group

Blower door
Bottom plate

Control door
Door knob assembly

Top filler plate

Electrical Group

3--Amp fuse

Circuit board
Control box

Door switch
Junction box
Limit switch(es)

Transformer

Blower Group

Blower housing

Blower motor
Blower wheel

Cut--off plate
Power choke (where used)

Filter Group

Filter(s)
Media Cabinet (when used)

Gas Control Group

Burner
Flame sensor

Gas valve
Hot surface igniter

Manifold
Orifice

Heat Exchanger Group

Containment plate
Coupling Box

Heat exchanger assembly
Primary HX cell panel
Secondary HX assembly

Tubing gaskets

Inducer Group

Collector box

Condensate trap
Condensate trap elbow

Gaskets
Inducer

Inducer assembly
Inducer motor capacitor (when used)
Inducer motor module (when used)

Pressure switch(es)

TO OBTAIN INFORMATION ON PARTS: Consult your installing dealer or classified section of your local telephone directory under
“Heating Equipment” or “Air Conditioning Contractors and Systems” headings for dealer listing by brand name or contact:

BRYANT HEATING & COOLING SYSTEMS

Consumer Relations Department

P.O. Box 4952

Syracuse, New York 13221--4952

1--800 --428--4326

Have available the model number, series number, and serial number located on the unit rating plate to ensure correct replacement part.

MODEL NOMENCLATURE

MODEL

926TB 66 120 V 24 A -- A

FIRE, EXPLOSION, ELECTRICAL SHOCK AND CARBON MONOXIDE POISONING HAZARD

Failure to follow this warning could result in dangerous operation, personal injury, death or property damage.

Improper installation, adjustment, alteration, service, or maintenance can cause personal injury, property damage, or death. Consult a
qualified installer, service agency, or your local gas supplier for information or assistance. The qualified installer or service agency
must use only factory--authorized replacement parts, kits, or accessories when modifying this product.

COOLING

CAPACITY

HEATING

CAPACITY

!

MOTOR WIDTH VO LTA G E

WARNING

FEATURES/

MINOR
SERIES

E2019 Bryant Heating & Cooling Systems D 7310 W. Morris St. D Indianapolis, IN 46231 Edition Date 07/19

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

84

Catalog No. II926TB--- 02

Replaces: II926TB--- 01