International comfort products A Series User manual

440 01 4601 01 12/4/2019
INSTALLATION INSTRUCTIONS
Single--Stage, 35--in. Tall
High Efficiency, Condensing, Ultra Low NOx Gas Furnace
N95ESU
(Series A)
NOTE: Read the entire instruction manual before starting the installation.
SECTIONS
SAFETY CONSIDERATIONS 4.........................
INTRODUCTION 5...................................
CODES AND STANDARDS 6...........................
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS 7...
ACCESSORIES 7.....................................
LOCATION 7........................................
AIR FOR COMBUSTION AND VENTILATION 8..........
CONDENSATE TRAP 11...............................
CONDENSATE DRAIN 11.............................
INSTALLATION 12...................................
AIR DUCTS 23.......................................
GAS PIPING 23......................................
ELECTRICAL CONNECTIONS 25.......................
VENTING 29........................................
START--UP, ADJUSTMENT, AND SAFETY CHECK 46......
SERVICE AND MAINTENANCE PROCEDURES 51........
WINTERIZATION 58..................................
SEQUENCE OF OPERATION 58........................
PARTS REPLACEMENT GUIDE 62......................
TABLES
Loose Parts Bag 5.....................................
Minimum Clearances to Combustible Materials 5.............
Minimum Free Area Required 10.........................
Minimum Space Volumes 10.............................
Filter Size Information 21...............................
Opening Dimensions 21................................
Air Delivery CFM 22...................................
Maximum Capacity of Pipe 24...........................
Electrical Data 28......................................
Vent Termination Kit for Direct Vent (2--Pipe) System 30.......
Hangar Spacing 36.....................................
Combustion--Air Vent Pipe, Fitting & Cement Material.. 39.....
Maximum Allowable Exposed Vent Lengths Insulation 40......
Maximum Equivalent Vent Length 40......................
Deductions from Maximum Equivalent Vent Length 40........
Altitude Derate Multiplier for U.S.A. 47....................
Orifice Size and Manifold Pressure 47.....................
Gas Rate 50..........................................
Blower Off Delay Setup Switch 60........................
Approved for installations up to 5,400 feet (1646 meters)
Use of the AHRI Certified TM Mark indicates a
manufacturer’s participation in the program.
For verification of certification for individual
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.

2440 01 4601 01
Specifications subject to change without notice.
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.

440 01 4601 01 3
Specifications subject to change without notice.
A190253
FURNACE SIZE
A
B C D SHIP WT.
LB (KG)
CABINET WIDTH OUTLET WIDTH BOTTOM INLET
WIDTH
A
IR INTAKE
0601716 1 7 --- 1
/
2 (445) 1 5 --- 7
/
8 (403) 16 (406) 8 --- 3
/
4 (222) 149.4 (67.8)
0802120 21 (533) 1 9 --- 3
/
8 (492) 1 9 --- 1
/
2 (495) 1 0 --- 1
/
2 (267) 167.4 (75.9)
1002120 21 (533) 1 9 --- 3
/
8 (492) 1 9 --- 1
/
2 (495) 1 0 --- 1
/
2 (267) 174.4 (79.1)
1002122 21 (533) 1 9 --- 3
/
8 (492) 1 9 --- 1
/
2 (495) 1 0 --- 1
/
2 (267) 175.4 (79.5)
Fig. 1 -- Dimensional Drawing

4440 01 4601 01
Specifications subject to change without notice.
SAFETY CONSIDERATIONS
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. These furnaces are not
approved for installation in recreational vehicles, outdoors or
in manufactured/mobile homes.
!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.
!WARNING
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.
CAUTION
!
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.
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.
CAUTION
!
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 spe-
cified in the “Location” section of these instructions.
3. Provide adequate combustion and ventilation air to the fur-
nace space as specified in “Air for Combustion and Ventila-
tion” section.
4. Combustion products must be discharged outdoors. Con-
nect this furnace to an approved vent system only, as spe-
cified in the “Venting” section of these instructions.
5. Never test for gas leaks with an open flame. Use a commer-
cially available soap solution made specifically for the de-
tection of leaks to check all connections, as specified in the
“Gas Piping” section.
6. Always install furnace to operate within the furnace’s inten-
ded temperature--rise range with a duct system which has an
external static pressure within the allowable range, as spe-
cified 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 contain-
ing the furnace, the return air shall also be handled by
duct(s) sealed to the furnace casing and terminating outside
the space containing the furnace. See “Air Ducts” section.
8. A gas--fired furnace for installation in a residential garage
must be installed as specified in the warning box in the
“Location” section.
9. The furnace is not permitted to be used for heating of build-
ings under construction.
10. These Upflow/Horizontal Gas--Fired Furnaces are CSA
design--certified for use with natural gas (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 and cannot be
converted to propane gas.
11. For required clearances to combustible construction (Table
1). Ensure sufficient clearance for furnace condensate trap
installation. See Location and Condensate Trap sections for
required and recommended clearances (Fig. 6 And Fig. 7).

440 01 4601 01 5
Specifications subject to change without notice.
Table 1 – Minimum Clearances to Combustible Materials for
All Units
POSITION CLEARANCE
REAR 1in.
FRONT
(Combustion air openings in
furnace and in structure)
1in.
Required for service 24 in.*
A
ll Sides of Supply Plenum 1in.
Sides 1in.**
Vent 0
Top of Furnace 1in.
* Consult local building codes.
** Additional clearance is required for condensate trap installation.
NOTE: Furnace edge contact is permissible with combustible
materials unless local codes state otherwise.
12. Maintain a 1--in. (25 mm) clearance from combustible ma-
terials 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.
13. These furnaces SHALL NOT be installed directly on carpet-
ing, combustible tile, or any other combustible material oth-
er than wood flooring. Clearance to combustible construc-
tion information (Table 1).
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.
NOTICE
INTRODUCTION
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 TO THE LEFT
OF THE BURNER SECTION,
AND CONDITIONED AIR IS
DISCHARGED TO THE RIGHT.
NOTE: Downflow not permitted.
A190213
Fig. 2 -- Upflow/Horizontal Orientations
This Upflow/Horizontal Category IV condensing furnace is CSA
design--certified as a direct--vent (2--pipe) furnace using outside air
for combustion. (Fig. 2). It is also certified as a non--direct vent
(1--pipe) furnace using indoor air for combustion or air from a
well--ventilated attic or crawl space, where permitted by local code.
The furnace is factory--shipped for use with natural gas only and
cannot be converted to propane gas.
These furnaces are not approved for installation in recreational
vehicles outdoors, or in manufactured/mobile homes. When
installed on a wood floor, the furnace must be installed on a
factory--supplied accessory combustible floor base or evaporator
coil casing.
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 (Fig. 3).
60
80 / 27˚C
/ 16˚C
SUPPLY AIR
SEE PRODUCT DATA FOR
ACCESSORY CONDENSATE
TRAP HEATER AND CONDENSATE
DRAIN LINE PROTECTION.
A150573
Fig. 3 -- Freeze Protection and Return Air Temperature
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 less than half of the
furnace model’s output capacity. 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 bags, and
literature before operating the furnace. The loose parts bag contains
more parts than needed (Table 2). The Ultra Low NOx condensing
furnaces also contain an additional parts bag for the condensate
trap, see Condensate Trap section.
Table 2 – Loose Parts Bag
DESCRIPTION QTY NOT
NEEDED
A
ir Intake Pipe Flange 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
Gas Line Grommet 1
Junction Bo
x
Cover 1
Junction Bo
x
Base 1
Green Ground Screw 1
Blunt Tip Screws (Junction Box) 3
Thermostat Wire Grommet 1
Pressure Switch Tube 1
X
Rubber Drain Elbow 1spare
Drain Tube Clamps 4
X
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
X

6440 01 4601 01
Specifications subject to change without notice.
BACK POSITIONED
DOWNWARD
AIR RETURN
CUT IN BACK
BACK POSITIONED
UPWARD
Downflow not permitted with any return air configuration.
A190256
Fig. 4 -- Prohibited Installations
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 (Fig. 4).
!WARNING
18-IN. (457.2 mm)
MINIMUM TO BURNERS
A93044
Fig. 5 -- Installation in a Garage
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, follow all codes and standards for the
following:
Safety
SCurrent edition of US: National Fuel Gas Code (NFGC) NFPA
54/ANSI Z223.1 and the Installation Standards, Warm Air
Heating and Air Conditioning Systems ANSI/NFPA 90B
General Installation
SUS: 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
Combustion and Ventilation Air
SUS: Current edition of Section 9.3 of the NFPA54/ANSI Z223.1
Air for Combustion and Ventilation
Duct Systems
SUS: Current edition of Air Conditioning Contractors Association
(ACCA) Manual D, Sheet Metal and Air Conditioning Contractors
National Association (SMACNA), or American Society of Heating,
Refrigeration, and Air Conditioning Engineers (ASHRAE)
Fundamentals Handbook Chapter 35
Acoustical Lining and Fibrous Glass Duct
SUS: 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
SUS: Current edition of NFPA 54/ANSI Z223.1 NFGC; Chapters
5, 6, 7, and 8 and national plumbing codes.
In the state of Massachusetts:
SThis product must be installed by a licensed plumber or gas fitter.
SWhen flexible connectors are used, the maximum length shall
not exceed 36 in. (914 mm).
SWhen lever type gas shutoffs are used they shall be T--handle type.
SThe use of copper tubing for gas piping is not approved by the
state of Massachusetts.
Electrical Connections
SUS: Current edition of National Electrical Code (NEC) NFPA
70
Condensate Drain Connection
SUS: Current edition of National Standard Plumbing Code,
Section 8.7.

440 01 4601 01 7
Specifications subject to change without notice.
ELECTROSTATIC DISCHARGE (ESD)
PRECAUTIONS PROCEDURE
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.
CAUTION
!
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 fur-
nace chassis which is close to the control. Tools held in a
person’s hand during grounding will be satisfactorily dis-
charged.
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 (ungroun-
ded) 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 con-
trol 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 Specification Sheet for a list of accessories for this product.
LOCATION
PERSONAL RELIABILITY HAZARD
Failure to follow this caution may result in unit component
damage.
Furnace may not be used for heating buildings under
construction.
CAUTION
!
IMPORTANT: Clearances for Condensate Trap
Before locating furnace, refer to condensate trap installation
instructions section for required clearances for trap installation.
Representative drawing only, some models may vary.
A190356
Fig. 6 -- 15” Trap Clearance in Horizontal Application
NOTE: Local codes may require a drain pan and condensate
tray when a condensing furnace is installed over a finished
ceiling.
Representative drawing only, some models may vary.
FACTORY SUPPLIED
CONDENSATE
FLOAT SWITCH
FACTORY SUPPLIED
3/4” PVC TEE DRAIN
DRAINTEECANBE
ROTATED FORWARD
FOR NARROW
INSTALLATIONS
TO OPEN DRAIN
A190317
Fig. 7 -- Trap Clearance in Upflow Application
General
These furnaces are shipped with materials to assist in proper
furnace installation. These materials are shipped in the main blower
compartment.
Loose parts bag contents (Table 2).
This furnace must:
Sbe installed so the electrical components are protected from
water.
Snot be installed directly on any combustible material other than
wood flooring (refer to SAFETY CONSIDERATIONS).
Sbe located close to the chimney or vent and attached to an air
distribution system. Refer to Air Ducts section.
Sbe provided ample space for servicing and cleaning. Always
comply with minimum fire protection clearances (Table 1).

8440 01 4601 01
Specifications subject to change without notice.
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.
!WARNING
The following types of furnace installations may require
OUTDOOR AIR for combustion due to chemical exposures:
SCommercial buildings
SBuildings with indoor pools
SLaundry rooms
SHobby or craft rooms
SChemical 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:
SPermanent wave solutions
SChlorinated waxes and cleaners
SChlorine based swimming pool chemicals
SWater softening chemicals
SDe--icing salts or chemicals
SCarbon tetrachloride
SHalogen type refrigerants
SCleaning solvents (such as perchloroethylene)
SPrinting inks, paint removers, varnishes, etc.
SHydrochloric acid
SCements and glues
SAntistatic fabric softeners for clothes dryers
SMasonry 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.
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 (Fig.5).
!WARNING
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. Refer to
Installation of Evaporator Coil section for install requirements for
unshielded coils (Table 6).
AIR FOR COMBUSTION AND
VENTILATION
Introduction
2--pipe Applications
When the furnace is installed as a 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 ensure
that other gas appliances have sufficient air for combustion.
1--pipe Applications
When the furnace is installed as a 1-pipe furnace, it will be
necessary to ensure 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 ensure 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 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 ensure 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 ensure that other gas appliances have sufficient air
for combustion.
Provisions for adequate combustion, ventilation, and dilution air
must be provided in accordance with:
SU.S.A. Installations: Current edition of Section 9.3 of the NFPA
54/ANSI Z223.1 , Air for Combustion and Ventilation and
applicable provisions of the local building codes.
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.
CAUTION
!

440 01 4601 01 9
Specifications subject to change without notice.
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.
!WARNING
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.
SSpaces having less than 50 cubic feet per 1,000 Btuh (4.8 cubic
meters per kW) require the Outdoor Combustion Air Method.
SSpaces 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 hori-
zontal or vertical duct(s) or opening(s) directly communicat-
ing with the outdoors or spaces that freely communicate
with the outdoors.
2. Provide TWO OUTDOOR OPENINGS, one inlet and
one outlet combustion and ventilation air opening, to the
outdoors (Fig. 8).
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 (Fig. 8 and Table 3).
c. TWO HORIZONTAL DUCTS require 1 sq. in. (645 sq.
mm) of free area per 2,000 Btuh (1,100 mm2/kW) of com-
bined input for all gas appliances in the space (Fig. 8 and
Table 3).
d. TWO OPENINGS OR VERTICAL DUCTS require 1
sq. in. (645 sq. mm) of free area per 4,000 Btuh (550
mm2/kW) for combined input of all gas appliances in the
space (Fig. 8 and Table 3).
3. ONE OUTDOOR OPENING requires:
a. 1 sq. in. (645 sq. mm) of free area per 3,000 Btuh (734
mm2/kW) for combined input of all gas appliances in the
space (Fig. 8 and Table 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.
Indoor Combustion AirENFPA & AGA
Standard and Known--Air--Infiltration Rate Methods
Indoor air is permitted for combustion, ventilation, and dilution, if
the Standard or Known--Air--Infiltration Method is used.
CARBON MONOXIDE POISONING HAZARD
Failure to 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.
!WARNING
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 (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 Volumes 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:
Volume
Other
=21ft
3
ACH
I
other
1000 Btu/hr
A04002
2. For fan--assisted appliances such as this furnace:
Volume
Fan
=15ft
3
ACH
I
fan
1000 Btu/hr
A04003
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 free area of at least 1 in.2/1,000 Btuh (2,000 mm2/kW)
of the total input rating of all gas appliances in the space,
but not less than 100 in.2(0.06 m2). One opening shall
commence within 12 in. (300 mm) of the ceiling and the
second opening shall commence within 12 in. (300 mm)
of the floor. The minimum dimension of air openings shall
be at least 3 in. (80 mm). (Fig. 9)
c. Combining space on different floor levels. The volumesof
spaces on different floor levels shall be considered as com-

10 440 01 4601 01
Specifications subject to change without notice.
municating spaces if connected by one or more permanent
openings in doors or floors having free area of at least 2
in.2/1,000 Btuh (4,400 mm2/kW) of total input rating of
all gas appliances.
2. An attic or crawlspace may be considered a space that freely
communicates with the outdoors provided there are ad-
equate permanent ventilation openings directly to outdoors
having free area of at least 1--in.2/4,000 Btuh of total input
rating for all gas appliances in the space.
3. In spaces that use the Indoor Combustion Air Method, in-
filtration 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.
Combination of Indoor and Outdoor Air
1. Indoor openings shall comply with the Indoor Combus-
tion Air Method below and,
2. Outdoor openings shall be located as required in the Out-
door 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 be-
low.
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-
quired in Outdoor Combustion Air Method above multi-
plied by reduction Factor in b. above. The minimum di-
mension of air openingsshall be notless than 3 in. (80 mm).
Table 3 – Minimum Free Area Required for Each Combustion Air Opening or Duct to Outdoors
FURNACE
INPUT
(BTUH)
TWO HORIZONTAL DUCTS
(1 SQ. IN./2,000 BTUH)
(1,100 SQ. MM/KW)
SINGLE DUCT OR OPENING
(1 SQ. IN./3,000 BTUH)
(734 SQ. MM/KW)
TWO OPENINGS OR
VERTICAL DUCTS
(1 SQ. IN./4,000 BTUH)
(550 SQ. MM/KW)
Free Area of
Opening and
Duct
Sq. In (Sq. mm)
Round Duct
In. (mm) Dia
Free
A
rea of
Opening and
Duct
Sq. In (Sq. mm)
Round Duct
In. (mm) Dia
Free Area of
Opening and
Duct
Sq. In (mm)
Round Duct
In. (mm) Dia.
60,000 30 (19355) 6 (152) 20 (13043) 5 (127) 15 (9678) 5 (127)
80,000 40 (25807) 7 (178) 27 (17391) 6 (152) 20 (12904) 5 (127)
100,000 50 (32258) 8 (203) 34 (21739) 7 (178) 25 (16130) 6 (152)
EXAMPLES: Determining Free Area
FURNACE WATER HEATER TOT
A
LINPUT
60,000 + 40,000 = (100,000 divided by 3,000) = 33.3 Sq. In.
f
or each Single Duct or Opening
80,000 + 30,000 = (110,000 divided by 2,000) = 55.0 Sq. In.
f
or each two Horizontal Ducts
100,000 +30,000 =(130,000 divided by 4,000) =32.5 Sq. In.
f
or each two Vertical Ducts or Openings
Table 4 – Minimum Space Volumes for 100% Combustion, Ventilation and Dilution Air from Outdoors
AIR
CHANGES
PER
HOUR
(ACH)
OTHER THAN FAN-ASSISTED
TOTAL
(1,000’S BTUH GAS INPUT
RATE)
F
A
N-
A
SSISTED TOTAL
(1,000’S BTUH GAS INPUT RATE)
30 40 50 26 40 60 80 100 120 140
Space
V
olume Ft
3
(M
3
)
0.60 1,050
(29.7)
1,400
(39.6)
1,750
(49.5) 910 (25.8) 1,400 (39.6)
1,500
(42.5)
2,000
(56.6)
2,500
(70.8)
3,000
(84.9)
3,500
(99.1)
0.50 1,260
(35.6)
1,680
(47.5)
2,100
(59.4)
1092
(30.9)
1,680
(47.5)
1,800
(51.0)
2,400
(67.9)
3,000
(84.9)
3,600
(101.9)
4,200
(118.9)
0.40 1,575
(44.5)
2,100
(59.4)
2,625
(74.3)
1365
(38.7)
2,100
(59.4)
2,250
(63.7)
3,000
(84.9)
3,750
(106.1)
4,500
(127.3)
5,250
(148.6)
0.30 2,100
(59.4)
2,800
(79.2)
3,500
(99.1)
1820
(51.5)
2,800
(79.2)
3,000
(84.9)
4,000
(113.2)
5,000
(141.5)
6,000
(169.8)
7,000
(198.1)
0.20 3,150
(89.1)
4,200
(118.9)
5,250
(148.6)
2730
(77.3)
4,200
(118.9)
4,500
(127.3)
6,000
(169.8)
7,500
(212.2)
9,000
(254.6)
10,500
(297.1)
0.10 6,300
(178.0)
8,400
(237.8)
10,500
(297.3)
5460
(154.6)
8,400
(237.8)
9,000
(254.6)
12,000
(339.5)
15,000
(424.4)
18,000
(509.2)
21,000
(594.1)
0.00 NP NP NP NP NP NP NP NP NP NP
NP = Not Permitted

440 01 4601 01 11
Specifications subject to change without notice.
*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. 8 -- 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.
L12F013
Fig. 9 -- Air for Combustion, Ventilation, and Dilution from
Indoors
CONDENSATE TRAP
Condensate Trap
The condensate trap is a field installed trap. A bag of loose parts
needed to construct the trap is provided with the furnace. The
assembled components of the trap (Fig. 16 and Fig. 17) are shown
with assembly instructions in the Installation section of this
manual. A float switch is included and must be installed in the trap
assembly and connected to the factory--provided wire harness
connections before furnace will operate.
CARBON MONOXIDE POISONING AND
PROPERTY DAMAGE HAZARD
Failure to follow this warning could result in property
damage, personal injury or death.
The condensate trap provided with furnace must be installed
per the furnace installation instructions. Do not modify the
trap beyond what is permitted or substitute a different trap.
!WARNING
The condensate trap extends below the underside of the casing
in the horizontal position. A minimum of 15--in. 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 of slope down.
NOTICE
CONDENSATE DRAIN CONNECTION
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 electric heat tape and/or RV
antifreeze is required for these installations.
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.
CAUTION
!
DO NOT trap condensate water in 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 heat tape kit is required. Refer
to the Accessory section of the Specification for 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) may be used to 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.
An indoor coil condensate drain or humidifier drain can be
connected to the external furnace condensate drain provided:
a. All condensate piping is at least 3/4-in. PVC and there is
a relief tee at the top of condensate drain piping (Fig. 11).
b. Connect the coil condensate drain downstream of the
furnace condensate trap.

12 440 01 4601 01
Specifications subject to change without notice.
FLOATSWITCHMUSTBE
PLUMBED IN THE FACTORY
SUPPLIED LOCATION.
DO NOT CHANGE THE
FACTORY SUPPLIED LOCATION
OF THE FURNACE
CONDENSATE DRAIN.
COIL CONDENSATE DRAIN
SHOULD NOT CONNECT
DIRECTLY TO THE FACTORY
SUPPLIED FURNACE
CONDENSATE TRAP.
A190319
FLOATSWITCHMUSTBE
PLUMBED IN THE FACTORY
SUPPLIED LOCATION.
DO NOT CHANGE THE
FACTORY SUPPLIED LOCATION
OF THE FURNACE
CONDENSATE DRAIN.
COIL CONDENSATE DRAIN
SHOULD NOT CONNECT
DIRECTLY TO THE FACTORY
SUPPLIED FURNACE
CONDENSATE TRAP.
A190320
BLOWER CREATES
POSITIVE PRESSURE
POSITIVE PRESSURE
EXTENDS FROM COIL
DRAIN TO THE FURNACE
CONDENSATE TRAP.
FURNACE CONDENSATE
DOES NOT FLOW
CONSISTENTLY WHEN
DRAIN IS AT POSITIVE
PRESSURE.
A190321
Fig. 10 -- Example of Field Drain Attachment (Not Allowed)
FACTORY
SUPPLIED
CONDENSATE
FLOAT
SWITCH
OPEN STANDPIPE
(OPTIONAL WHEN
COIL DRAIN IS NOT
CONNECTED TO
FURNACE DRAIN.)
A190309
OPEN STANDPIPE
(OPTIONAL WHEN
COIL DRAIN IS NOT
CONNECTED TO
FURNACE DRAIN.)
FACTORY
SUPPLIED
CONDENSATE
FLOAT
SWITCH
A190310
NOTE: Coil may require metal spacer or shield between furnace
and coil. See coil install requirements (Table 6).
NOTE: If condensate and coil drains are joined, must be joined
downstream of the furnace condensate trap float switch tee.
NOTE: Condensate float switch is for furnace draining only and
will not act as float switch for coil drain pan.
Fig. 11 -- Example of Field Drain Attachment
Upflow installations utilizing the right side air return opening
should follow the Upflow Specific Steps -- Offset Installation
to ensure the full opening is available for return ductwork.
NOTICE
INSTALLATION
Preparing the Furnace – Before Setting in Place
1. Remove appropriate knockout based off the installation
orientation.
2. Peel off green gasket from the collector box to allow more
room for hose clamps (Fig. 14).

440 01 4601 01 13
Specifications subject to change without notice.
Table 5 – Condensate Trap Bag Contents
DESCRIPTION QUANTITY
INST
A
LLATION CONFIGURATION
HORIZONT
A
LUPFLOW UPFLOW OFFSET
Trap Assembly 1
x
x
x
Switch with Float 1
x
x
x
Plastic Collar 1
x
x
x
Collar Gasket 1
x
x
x
Screws 8 6 6 8
Rubber Elbow 2
x
x
x
C l a m p --- W o r m D r i v e 4
x
x
x
Tu b e A ( . 5 --- i n .
x
2.75--- in.) 1
x
x
Tu b e B ( . 5 --- i n .
x
2.25--- in.) 1
x
x
Tu b e C ( . 5 --- i n .
x
3 . 5 --- i n . ) 1
x
Tu b e D ( . 5 --- i n .
x
4 . 5 --- i n . ) 1
x
Tu b e E ( . 5 --- i n .
x
13.5--- in.) 2
x
x
x
C P V C E l b o w --- 4 5 ° 2
x
C P V C E l b o w --- 9 0 ° 2
x
x
Upflow Bracket 1
x
x
Adapter Plate 1
x
Bolt 1
x
x
Nut 1
x
x
Pigtail Harness Assembly 1
x
x
x
Grommet 1
x
x
x
Wire Nuts 2
x
x
x
* 3 pieces of Trap Assembly may need to be assembled per Fig. 19.
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.
CAUTION
!
L12F019B
Fig. 12 -- Knockout Removal
IMPORTANT: Whenever sheet metal screws are used, it is
recommended to pre--drill 1/8--in. holes.
3. Cut the two (2) Rubber Elbows (Fig. 13). Each elbow
should only be cut once.
Rubber Elbow 1 Rubber Elbow 2
A190322
Fig. 13 -- Rubber Elbows
4. Remove two of the factory--installed drain plugs from
collector box. Orientation specific drain plugs (Fig. 14).
A190312
Fig. 14 -- Drain Plugs
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in property damage.
Over tightening hose clamps may crack plastic components
which may result in water leaks causing possible water
damage.
CAUTION
!
5. Install and tighten two (2) of the Worm Drive Clamps and
the two cut Rubber Elbows (Fig. 15). Torque the clamps to
hand--tight (15 lb--in.). Over tightening hose clamps may
crack plastic components which may result in water leaks
and possibly water damage.
TIP: It is helpful to use a ratcheting box wrench or a
ratcheting socket wrench to tighten the clamps. The long
end of Rubber Elbow 2 should be pointed towards the
collector box.

14 440 01 4601 01
Specifications subject to change without notice.
A190323
Fig. 15 -- Example of Hose Clamp Installation
6. If trap comes unassembled, the components will require
assembly (Fig. 19) with PVC glue. After assembly, firmly
press the Float Switch into the Trap Assembly.
7. The provided 3/4-in. PVC tube may be replaced with up to
24-in. of 3/4-in. PVC tube to allow for float switch tee to
extend past the furnace casing for easier service.
IMPORTANT: using a longer PVC tube to extend the float
switch is not allowed when the trap itself is installed in the
Remote Trap configuration.
CARBON MONOXIDE POISONING AND
PROPERTY DAMAGE HAZARD
Failure to follow this warning could result in property
damage, personal injury or death.
PVC trap components must be properly glued using PVC
glue. CPVC components must be properly glued using
CPVC glue.
!WARNING
CVPC
Elbows
Plastic Collar
& Gasket
Tube 1
Tube 2
Upflow Drain
Bracket
A190324
Fig. 16 -- Upflow Condensate Drain
CVPC
Elbows
Tube A
Tube 2
Plastic Collar
&Gasket
Upflow Drain
Bracket
Trap Assy
A190325
Fig. 17 -- Upflow -- Offset of Condensate Drain
Upflow Specific Steps – Standard Installation
1. Install and tighten remaining two (2) clamps and short
CPVC tubes (Fig. 15). The longer tube (Tube A) should be
installed in the upper most rubber elbow. Torque the clamps
to hand--tight (15 lb--in.). Over tightening hose clamps may
crack plastic components which may result in water leaks
and possibly water damage.
2. Remove adhesive backing from the Collar Gasket and apply
it to the rear side of the Collar Plate.
3. Place Collar Plate on over condensate drain knockout while
routing the short CPVC tubes through the Collar Plate.
4. Using four (4) of the sheet metal screws, screw the Plastic
Collar to the furnace casing through the four (4) holes in the
middle and top.
5. Install the Upflow Drain Bracket with two (2) sheet metal
screws to the bottom of the Collar Plate.
6. Assemble the two (2) E Tubes and Elbows (90°) to Tubes A
& B (Fig. 16). Ensure the two long tubes are pointed
downward before glue is set.
7. Set the Trap Assembly on the arms of the bracket and tight-
en with the provided bolt and nut. Ensure the bottom of the
large Tee is resting on the bracket (Fig. 18).
Bracket Arms
A190327
Fig. 18 -- Bracket Arms

440 01 4601 01 15
Specifications subject to change without notice.
FURNACE OPERATION HAZARD
Failure to follow this caution may result in furnace damage.
Special precautions MUST be made when installing
furnace. The condensate pipe with the float switch can not
be obstructed or used to directly drain the coil drain pan.
This can cause improper operation or damage to equipment.
The float switch must NOT be obstructed.
CAUTION
!
A190326
Fig. 19 -- Assembly of Main Trap Components with Float Switch
NOTE: PVC pieces must be glued using PVC glue to prevent
leaks.
Upflow Specific Steps – Offset Installation
1. Install short CPVC tubes (Fig. 15 or Fig. 17). The longer
tube (Tube A) should be installed in the upper most rubber
elbow. Torque the clamps to hand--tight (15 lb--in.). Over
tightening hose clamps may crack plastic components
which may result in water leaks and possibly water damage.
2. Remove adhesive backing from the Collar Gasket and apply
it to the rear side of the Collar Plate.
3. Place Collar Plate over condensate drain knockout while
routing the short CPVC tubes through the Collar Plate.
4. Using six (6) of the sheet metal screws, screw the Plastic
Collar to the furnace casing.
5. Remove two (2) blower shelf screws and install the Adapter
Plate. Using two (2) of the sheet metal screws provided,
attach the Upflow Bracket to the Adapter Plate (Fig. 17).
6. Assemble the Tubes (C, D, & E) and Elbows (45°&90°)
using PVC glue and connect to Tubes A & B (Fig. 17).
Ensure the two long tubes are pointed downward before
glue is set.
7. Set the Trap Assembly on the arms of the bracket and
tighten with the provided bolt and nut. Ensure the bottom of
the large Tee is resting on the bracket (Fig. 18).
8. Tighten remaining two (2) clamps connecting Tubes A & B
to the Rubber Elbows (Fig. 15). Torque the clamps to hand--
tight (15 lb--in.). Over tightening hose clamps may crack
plastic components which may result in water leaks and
possibly water damage.
A190382
Fig. 20 -- Horizontal -- Offset of Condensate Drain
Horizontal Specific Steps
1. Install and tighten remaining two (2) clamps and two (2)
long CPVC tubes (Fig. 15 and Fig. 21). Torque the clamps
to hand--tight (15 lb--in.). Over tightening hose clamps may
crack plastic components which may result in water leaks
and possibly water damage.
2. Remove adhesive backing from the Collar Gasket and apply
it to the rear side of the Collar Plate.
3. Slide the Plastic Collar approximately halfway up the tubes
and then slide the Trap Assembly over the long CPVC
tubes. You may need to push the long CPVC tubes towards
the back of the furnace during this step depending on the
clearance below the furnace (Fig. 21).
A190328
Fig. 21 -- Horizontal -- Trap Assembly Aid
4. Using six (6) of the sheet metal screws, screw the Plastic
Collar to the furnace.
5. Insert the Trap Assembly onto the Plastic Collar (Fig. 22).
Using two (2) sheet metal screws, fasten the condensate trap
assembly to the Plastic Collar.
Representative drawing only, some models may vary.
FACTORY SUPPLIED
CONDENSATE
FLOAT SWITCH
FACTORY SUPPLIED
3/4” PVC TEE DRAIN
FIELD SUPPLIED
5--- 3/4”
15”
A190315
Fig. 22 -- 15” Trap Clearance in Horizontal Application
(Note: Drain line can be run horizontally or vertically)
NOTE: Field Supplied Drain can be routed horizontally from
tee at top of the trap, allow at least 1/4--in. per foot of slope
down.
Extra water in transducer pressure tubing may inhibit furnace
operation because of incorrect pressure readings.
NOTICE
6. Remove collector box cap.
7. Remove transducer pressure tubing and trim transducer
pressure tubing length ensuring no traps or loops for extra
water collections. Install on the port where the collector box
cap was removed from (Fig. 14).

16 440 01 4601 01
Specifications subject to change without notice.
It is permissible to run the trap up to 5 ft. away from the furnace to
an area with the required trap clearance provided the following
steps and conditions are followed.
Alternate Horizontal Option --
Remote Trap Installation Specific Steps
1. Glue included 90CPVC elbows to shortest two CPVC
Tubes (A and B) or replace with two field supplied 1/2-in.
CPVC tubes of the desired length (5 ft. or less) to extend
out of the cabinet.
2. Remove adhesive backing from the Collar Gasket and apply
it to the rear side of the Collar Plate.
3. Place Collar Plate over condensate drain knockout and
fasten to cabinet with six (6) of the sheet metal screws.
4. Install elbow and tube assemblies by routing tubes through
collar plate and inserting the ends into the rubber elbows
previously installed on the collector box. Ensure elbows are
pointed toward desired trap location before tightening the
clamps.
5. Torque the clamps to hand--tight (15 lb--in.). Over
tightening hose clamps may crack plastic components
which may result in water leaks and possibly water damage.
6. Attach the field supplied 1/2-in. CPVC tubing for the
remote run to the 90elbows that extend past the casing.
Run the two drain lines up to 5 ft away from where they
exit the furnace casing to reach the remote trap location. All
condensate drain line joints must be glued with CPVC glue.
7. Use provided tubes (Tube E) to extend into the main body
of the trap and CPVC elbows MUST touch the top of the
PVC tube of the main trap.
A190392
Fig. 23 -- Tubes on top of Trap
8. Mount included Upflow Bracket to structure ensuring
condensate drain is sloped 1/4-in. per foot and that the
CPVC elbows rest on top of the PVC tube of the main trap
(Fig. 24).
9. Set the Trap Assembly on the arms of the Upflow Bracket
and tighten with the provided bolt and nut. Ensure the
bottom of the large Tee is resting on the bracket (Fig. 18).
A190393
Fig. 24 -- Alternate Horizontal Option -- Remote Trap
Finishing Installation
1. Route the float switch wires through a Plastic Grommet and
then through a knockout to the blower compartment. Adjust
Plastic Grommet so that it seals the cabinet.
2. Using wire nuts, make connection between Float Switch
and Pigtail Harness Assembly. Lastly, join the 2 pin
receptacle from the Pigtail with the 2 pin receptacle that
originates from the control board 12--pin connector.
Alternate Horizontal Option -- Remote Trap may require
additional field supplied wire to make connection between
float switch and pigtail harness assembly connected to
control board.
3. If the installation is a Direct Vent application, apply silicone
or duct putty around the CPVC tubes passing through the
clearance holes in the Plastic Collar to fully seal the
combustion vestibule.
4. The remaining drain line can be constructed from field sup-
plied 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.
5. 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.
6. 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.
Installation of Evaporator Coils
When installing the evaporator coil, refer to the allowed installation
configurations (Table 6). Some coils require an 8--in. tall sheet
metal spacer between the furnace and the coil or some require a
metal shield between the drain pan of the coil and the discharge
flanges of the furnace. This is to protect the composite drain pan of
the evaporator coil. The coil offset adapter kits in the product
accessory list will require an additional field fabricated adapter to
ensure the 8--in. separation.
FIRE HAZARD
When installing evaporator coils that have composite
(plastic) drain pans and are exposed directly to the furnace
heat exchanger, a sheet metal spacer/transition or drain pan
shield is required.
Failure to protect the coil composite drain pan could result
in fire, personal injury, or death. (Table 6)
!WARNING

440 01 4601 01 17
Specifications subject to change without notice.
Table 6 – Evaporator Coil Spacer or Shield Requirements.
Ty pe o f C o i l Install Flush to
Furnace
Install with
8 --- i n . S p a c e r
Install with
Metal Shield
Furnace Manufacturer’s
NCoil
A
llowed Not Required Not Required
Furnace Manufacturer’s
ACoil Not
A
llowed
A
llowed
(Except 100k
BTU size in
Horizontal Right
--- MUST use
shield)
A
llowed
(See Note 2)
3 r d P a r t y C o i l --- F a c t o r y
Shielded (See Note 1)
A
llowed Not Required Not Required
3 r d P a r t y C o i l ---
Unshielded Not
A
llowed
A
llowed
(Except 100k
BTU size in
Horizontal Right
--- MUST use
shield)
A
llowed
(See Note 3)
NOTE:
1. 3rd Party Coils that are factory--supplied with a metallic
shield over the plastic composite drain pan must completely
shield all plastic composite materials from direct exposure
to any part of the heat exchanger. Consult with 3rd Party
Manufacturer to ensure coil is properly shielded. Coils that
are only partially shielded should be treated as un--shielded
and require a spacer.
2. Field--fabricated metallic shield must completely shield all
plastic composite materials from direct exposure to any part
of the heat exchanger. Coils that are only partially shielded
should be treated as un--shielded and require a spacer.
Dimensional requirements (Fig. 26).
3. For 3rd party unshielded coils, consult manufacturer for
design of a field--fabricated shield that completely shields
all plastic composite materials from direct exposure to any
part of the heat exchanger.
All adapters are field fabricated according to the dimensions for the
metal shield (Fig. 25) and for the 8--in. tall sheet metal spacer (Fig.
26).
Representative drawing only, some models may vary.
A---COIL SHIELD
3-- 3/4
A+7.5
20 --- 1/2
3-- 1/2
1-- 1/2
3-- 3/4
16-- 1/2
3-- 1/2
FRONT
A190295
Representative drawing only, some models may vary.
Furnace
Coil
Furnace
A190296
Cabinet Size Dimension “
A
”
1 7 --- i n . 1 0 --- i n .
2 1 --- i n . 13.5---in.
Fig. 25 -- Dimensions Metal Shield
NOTE: The metal shield in the figure above is only recommended
for use with furnace manufacturer’s A--Coil and may not be
compatible with 3rd party coils. In the event the shield shown
above is incompatible with the desired coil, use a spacer or consult
3rd Party Manufacturer for recommended dimensions and design
of suitable shield.
Representative drawing only, some models may vary.
Coil Spacer
Furnace
Coil
Furnace
20 --- 1/2” B
8
”
A190301
Cabinet Size Dimension “B”
1 7 --- i n . 1 7 --- 1
/
2 --- i n .
2 1 --- i n . 2 1 --- i n .
Fig. 26 -- Dimensions of 8--in. Tall Metal Spacer
NOTE: The allowable use of the 8--in. spacer demonstration
(Table 6 and Fig. 26). The spacer may taper to accommodate
different coil/furnace width combinations but must always keep an
8--in. minimum height if used. Space between the top of the
furnace casing and the bottom of the coil.
NOTE: When the indoor coil is placed in an unconditioned space,
insulation should be applied and wrapped around the outside of
coil casing, 8--in. adapter and supply duct contact point.
1. Create field fabricated adapter (if needed, Table 6).
2. If adapter is needed, place field fabricated adapter on
furnace. Adapter should be tapered to fit coil/furnace
combination when one of them is larger than the other.
3. Set coil on adapter.
4. Ensure coil is level for proper condensate drainage. In
upflow application, do not tip coil toward condensate drain.
In the horizontal application, ensure coil cabinet is level side
to side and front to back. It is allowable to add up to 1/2--in
additional slope over length and depth of coil cabinet in the
direction of drain pan connection.
5. Attach coil casing to furnace using sheet metal screws. If
8--in. spacer is required, attach coil casing to spacer and
attach spacer to furnace using sheet metal screws.
6. Seal joints between coil casing, adapter (if needed, Table 6),
and furnace to create an air tight seal using locally approved
materials.
Upflow Installation
NOTE: The furnace must be pitched for proper condensate
drainage (Fig. 29).
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.

18 440 01 4601 01
Specifications subject to change without notice.
Connect supply--air duct to flanges on furnace supply--air outlet.
Bend flange upward to 90_with wide duct pliers (Fig. 27). 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.
Representative drawing only, some models may vary.
Fig. 27 -- Duct Flanges
Representative drawing only, some models may vary.
A190216
Fig. 27 Duct Flanges (continued)
NOTE: Coil offset kits do not meet the 8---in. separation between the coil
pan and furnace if required (Table 6). Additional metal shield or an
extension to achieve an 8 ---in. total separation is required.
Return Air Connections
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.
!WARNING
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 (Fig. 30 and Fig. 31).
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 (Fig.
34).
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: For allowable side returns in horizontal configurations
(Fig. 31).
Leveling Legs (If Desired)
In upflow position with side return inlet(s), leveling legs may be
used. (Fig. 28). 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 (Fig. 34).
To install leveling legs:
1. Position furnace on its back. Locate and drill a hole in each
bottom corner of furnace.
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 in-
side nut to secure arrangement.
5. Reinstall bottom closure panel if removed.
1
3
/ 4 
1
3
/ 4 
1
3/
4 
1
3/
4 
5/
16 
5
/ 16 
5/
16 
5/
16 
(44mm)
(8mm)
(44mm)
(8mm)
(8mm)
(8mm)
(44mm)
(44mm)
A89014
Fig. 28 -- Leveling Legs
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.
CAUTION
!

440 01 4601 01 19
Specifications subject to change without notice.
Horizontal Installation
NOTE: The furnace must be pitched forward for proper
condensate drainage (Fig. 29).
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.
!WARNING
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.
CAUTION
!
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
UPFLOW OR
DOWNFLOW HORIZONTAL
MIN 1/4-IN. (6 MM) TO
1/2-IN. (13 MM) MAX
A11237
Fig. 29 -- Furnace Pitch Requirements
Platform Furnace Support
Construct working platform at location where all required furnace
clearances are met. (Table 1 and Fig. 32) 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. Condensate Trap section for required and
recommended clearances for trap installation (Fig. 6, Fig 22, and
Fig. 32).
Suspended Furnace Support
The furnace must be supported under the entire length of the
furnace with threaded rod and angle iron (Fig. 33). 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
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.
Upflow installations utilizing the right side air return opening
should follow the Upflow Specific Steps -- Offset Installation
to ensure the full opening is available for return ductwork.
NOTICE
A190214
Fig. 30 -- Upflow Return Air Configurations and Restrictions
A190215
Fig. 31 -- Horizontal Return Air Configurations and
Restrictions

20 440 01 4601 01
Specifications subject to change without notice.
Re
p
resentative drawin
g
onl
y
, some models ma
y
var
y
.
A190318
Fig. 32 -- Working Platform for Attic Installation
NOTE: Furnace shown is a direct vent application. Refer to the
venting section for allowable vent configurations.
NOTE: N Coil only, add 8--in. separation between coil and
furnace for all other unshielded coils. (See evaporator coil spacer or
shield requirements.)
NOTE: Local codes may require a drain pan and condensate trap
when a condensing furnace is installed over a finished ceiling.
Representative drawing only, some models may vary.
15”
15” clearance
needed for trap
height
A190306
Fig. 33 -- Suspended Furnace Installation
NOTE: Furnace shown is a direct vent application. Refer to the
venting section for allowable vent configurations.
NOTE: N Coil only, add 8--in. separation between coil and
furnace for all other unshielded coils. (See evaporator coil spacer or
shield requirements.)
NOTE: Local codes may require a drain pan and condensate trap
when a condensing furnace is installed over a finished ceiling.
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 (Fig. 27). 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 (Fig. 31).
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 (Fig.
34).
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 (Fig. 31). Where required by code, seal bottom closure
to furnace with tape, mastic, or other durable sealing method.
Representative drawing only, some models may vary.
SCREWS
(2)
BOTTOM
CLOSURE
A170123
1 Lay furnace on the back or side
2 Remove the two (2) screws that secure the bottom
closure panel to the furnace casing and remove the
panel
Fig. 34 -- Removing Bottom Closure Panel (2 Screws)