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