Carrier Minor 2 Series Guide

Installation, Start-up, Operating and Service and Maintenance
Instructions
NOTE: Read the entire instruction manual before starting the
installation.
Approved for installations up to 5,400 feet (1646 meters)
TABLE OF CONTENTS
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Table 1 – Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
CODES AND STANDARDS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS PROCE-
DURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
LOCATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Table 2 – Minimum Free Area Required for Each Combustion Air
Opening or Duct to Outdoors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Table 3 – Minimum Space volumes for 100% combustion, Ventila-
tion, and Dilution from Indoors . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
AIR FOR COMBUSTION AND VENTILATION . . . . . . . . . . . . . . 6
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Table 4 – Opening Dimensions - In. (mm) . . . . . . . . . . . . . . . . . 10
Table 5 – Air Delivery - CFM (with filter) . . . . . . . . . . . . . . . . . 12
GAS PIPING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Table 6 – Maximum Capacity of Pipe* . . . . . . . . . . . . . . . . . . . . 13
Table 7 – Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Table 8 – Combined Appliance Maximum Input Rating in Thousands
of BTUH per Hour . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Table 9 – Minimum Allowable Input Rating of Space-Heating Appli-
ance in Thousands of BTUH per Hour . . . . . . . . . . . . . . . . . . . . 18
START-UP, ADJUSTMENT, AND SAFETY CHECK . . . . . . . . . 20
Table 10 – Altitude Derate Multiplier for U.S.A. . . . . . . . . . . . . 21
Table 11 – Gas Rate (Cu Ft./Hr.) . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 12 – Gas Valve Outlet Pressure for Gas Heat Values at Altitude
- 40,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 13 – Gas Valve Outlet Pressure for Gas Heat Values at Altitude
- 60,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Table 14 – Gas Valve Outlet Pressure for Gas Heat Values at Altitude
- 80,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 15 – Gas Valve Outlet Pressure for Gas Heat Values at Altitude
- 100,000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
SERVICE AND MAINTENANCE
PROCEDURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Table 16 – Filter Size Information (In. / mm) . . . . . . . . . . . . . . . 27
SERVICE GUIDE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
PARTS REPLACEMENT INFORMATION GUIDE . . . . . . . . . . . 34
EXAMPLE OF MODEL NUMBER . . . . . . . . . . . . . . . . . . . . . . . . 34
A200103
Most states in the USA and jurisdictions in Canada have laws that
require the use of Carbon Monoxide (CO) alarms with fuel burning
products. Examples of fuel burning products are furnaces, boilers, space
heaters, generators, water heaters, stoves/ranges, clothes dryers,
fireplaces, incinerators, automobiles, and other internal combustion
engines. Even if there are no laws in your jurisdiction requiring a CO
Alarm, it’s highly recommended that whenever any fuel burning product
is used in or around the home or business that the dwelling be equipped
with a CO Alarm(s). The Consumer Product Safety Commission
recommends the use of CO Alarm(s). The CO Alarm(s) must be
installed, operated, and maintained according to the CO Alarm
manufacturer’s instructions. For more information about Carbon
Monoxide, local laws, or to purchase a CO Alarm online, please visit the
following website. https://www.kidde.com.
Portions of the text and tables are reprinted from current edition of 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.
58SU0A
80% AFUE, Single Stage, ECM Motor, Ultra Low NOx,
4-Way Multipoise, Non-Condensing, Gas Furnace
(Minor Series 2 & 3)
WARNING
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury and/or
death.
Carbon Monoxide (CO) is a colorless, odorless, and tasteless poisonous
gas that can be fatal when inhaled. Follow all installation, maintenance,
and service instructions. See additional information below regarding
the installation of a CO Alarm.
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 .

58SU0A: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
2
SAFETY CONSIDERATIONS
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.
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 include in literature and
attached to the unit. Consult local building codes, the current editions of
the current edition of National Fuel Gas Code (NFGC) NFPA 54/ANSI
Z223.1 and the current edition of National Electrical Code (NEC) NFPA
70.
Recognize safety information. This is the safety-alert symbol . When
you see this symbol on the unit 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 hazards which could result in personal
injury or death. CAUTION is used to identify unsafe practices which
may result in minor personal injury or product and property damage.
NOTE is used to highlight suggestions which will result in enhanced
installation, reliability, or operation.
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.
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.
8. A gas-fired furnace for installation in a residential garage must be
installed as specified in the warning box in the “Location” section,
see Fig. 5.
9. The furnace is not permitted to be used for heating of buildings
under construction.
10. These Multipoise Gas-Fired Furnaces are CSA (formerly A.G.A.
and C.G.A). design-certified for use with natural 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. See Fig. 2 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 inches (914 mm)
horizontally from the furnace. See current edition of NFPA 90B or
local code for further requirements.
13. These furnaces SHALL NOT be installed directly on carpeting, tile,
or any other combustible material other than wood flooring. In
downflow installations, factory accessory floor base MUST be used
when installed on combustible materials and wood flooring. Special
base is not required when this furnace is installed on manufacturer’s
approved coil assembly or a manufacturer’s coil casing box is used.
See Fig. 2 for clearance to combustible construction.
INTRODUCTION
This 4-way multipoise Category I fan-assisted furnace is CSA
design-certified. A Category I fan-assisted furnace is an appliance
equipped with an integral mechanical means to either draw or force
products of combustion through the combustion chamber and/or heat
exchanger. The furnace is factory-shipped for use with natural gas.
This furnace is not approved for installation in mobile homes,
recreational vehicles, or outdoors. The furnace is not permitted to be
used for heating of buildings under construction. This furnace is
designed for minimum continuous return-air temperature of 60°°F
(16°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. 3.
For accessory installation details, refer to the applicable instruction
literature.
NOTE: Remove all shipping brackets and materials before operating the
furnace.
WARNING
!
FIRE, EXPLOSION, ELECTRICAL SHOCK, AND
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in dangerous operation,
serious injury, death, or property damage.
Improper installation, adjustment, alteration, service, maintenance, or
use could 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.
CAUTION
!
FURNACE RELIABILITY HAZARD
Improper installation or misapplication of furnace may require
excessive servicing or cause premature component failure.
Application of this furnace should be indoors with special attention
given to vent sizing and material, gas input rate, air temperature rise,
unit leveling, and unit sizing.

58SU0A: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
3
A190257
Fig. 1 – Dimensional Drawing
Table 1 – Dimensions
FURNACE SIZE
A
CABINET
WIDTH
IN. (MM)
B
OUTLET
WIDTH
IN. (MM)
C
TOP FLUE
COLLAR ONLY
IN. (MM)
D
BOTTOM
INLET WIDTH
IN. (MM)
VENT
CONNECTIO
N
IN. (MM) SIZE
SHIP WT.
LB. (KG)
ACCESSORY
FILTER
MEDIA
CABINET SIZE
IN. (MM)
040E17--12 17-1/2 (445) 15-7/8 (403) 11-9/16 (294) 16 (406) 4 (102) 118 (54) 16 (406)
060E17--16 17-1/2 (445) 15-7/8 (403) 11-9/16 (294) 16 (406) 4 (102) 126 (57) 16 (406)
080E21--20 21 (533) 19-3/8 (492) 13-5/16 (338) 19-1/2 (495) 4 (102) 140 (64) 20 (508)
100E21--20 21 (533) 19-3/8 (492) 13-5/16 (338) 19-1/2 (495) 4 (102) 150 (68) 20 (508)
NOTE: ALL DIMENSIONS IN INCH (MM) U.S. ECCN: Not Subject to Regulation (N.S.R.)
SD5507- 4 ULN 80 REV. B

58SU0A: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
4
A190402
Fig. 2 – Clearances to Combustibles
A02055
Fig. 3 – Return Air Temperature
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
• USA: 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
General Installation
• Current edition of the NFGC and the NFPA 90B. For copies, contact
the National Fire Protection Association Inc., Batterymarch Park,
Quincy, MA 02269; (www.NFPA.org) or for only the NFGC, contact
the American Gas Association, 400 N. Capitol Street, N.W.,
Washington, DC 20001 (www.AGA.org).
Combustion and Ventilation Air
• Current edition of NFGC NFPA54/ANSI Z223.1 Section 9.3, Air for
Combustion and Ventilation.
Duct Systems
• 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) 2005 Fundamentals Handbook
Chapter 35 or 2004 HVAC Systems and Equipment Handbook
Chapters 9 and 16.
Acoustical Lining and Fibrous Glass Duct
• Current edition of SMACNA and NFPA 90B as tested by UL Standard
181 for Class I Rigid Air Ducts
Gas Piping and Gas Pipe Pressure Testing
• Current edition of NFGC NFPA54/ANSI Z223.1; chapters 5, 6, 7, and
8 and National Plumbing Codes.
Electrical Connections
• Current edition of National Electrical Code (NEC) NFPA 70.
Venting
• Current edition of NFGC NFPA 54 / ANSI Z223.1; Chapters 12 and
13.
ELECTROSTATIC DISCHARGE (ESD)
PRECAUTIONS PROCEDURE
1. Disconnect all power to the furnace. Multiple disconnects maybe
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. 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.
Min 60ºF / 16ºC
Max 85ºF/ 29ºC
CAUTION
!
FURNACE RELIABILITY HAZARD
Improper installation or service of furnace may cause premature
furnace component failure.
Electrostatic discharge can affect electronic components. Follow the
Electrostatic Discharge Precautions Procedure listed below 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.

58SU0A: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
5
7. An ESD service kit (available from commercial sources) may also
be used to prevent ESD damage.
A02097
Fig. 4 – Multipoise Orientations
LOCATION
GENERAL
This multipoise furnace is shipped in packaged configuration. Some
assembly and modifications are required when used in any of the four
applications shown in Fig. 4.
This furnace must:
• be installed so the electrical components are protected from water.
• not be installed directly on any combustible mateial other than wood
flooring for upflow applications. Downflow installations require use
of a factory-approved floor base or coil assembly when installed on
combustible materials or wood flooring (refer to SAFETY
CONSIDERATIONS).
• be located close to the chimney or vent and attached to an air
distribution system. Refer to Air Ducts section.
• be provided ample space for servicing and cleaning. Always comply
with minimum fire protection clearances shown on the furnace
clearance to combustible label.
The following types of furnace installations may require OUTDOOR
AIR for combustion due to chemical exposures:
• Commercial buildings
• Buildings with indoor pools
• Laundry rooms
• Hobby or craft rooms, and
• Chemical storage areas
If air is exposed to the following substances, it should not be used for
combustion air, and outdoor air may be required for combustion:
• Permanent wave solutions
• Chlorinated waxes and cleaners
• Chlorine based swimming pool chemicals
• Water softening chemicals
• De-icing salts or chemicals
• Carbon tetrachloride
• Halogen type refrigerants
• Cleaning solvents (such as perchloroethylene)
• Printing inks, paint removers, varnishes, etc.
• Hydrochloric acid
• Cements and glues
• Antistatic fabric softeners for clothes dryers
• Masonry acid washing materials
All fuel-burning equipment must be supplied with air for fuel
combustion. Sufficient air must be provided to avoid negative pressure
in the equipment room or space. A positive seal must be made between
the furnace cabinet and the return-air duct to prevent pulling air from the
burner area and from draft safeguard opening.
A93044
Fig. 5 – Installation in a Garage
WARNING
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal injury or death,
and unit component damage.
Corrosive or contaminated air may cause failure of parts containing flue
gas, which could leak into the living space. Air for combustion must not
be contaminated by halogen compounds, which include fluoride,
chloride, bromide, and iodide. These elements can corrode heat
exchangers and shorten furnace life. Air contaminants are found in
aerosol sprays, detergents, bleaches, cleaning solvents, salts, air
fresheners, and other household products. Do not install furnace in a
corrosive or contaminated atmosphere. Make sure all combustion and
circulating air requirements are met, in addition to all local codes and
ordinances.
THE BLOWER IS LOCATED
TO THE RIGHT OF THE
BURNER SECTION, AND
AIR CONDITIONED AIR IS
DISCHARGED TO THE LEFT.
THE BLOWER IS
LOCATED BELOW THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED UPWARD.
THE BLOWER IS
LOCATED ABOVE THE
BURNER SECTION, AND
CONDITIONED AIR IS
DISCHARGED DOWNWARD
THE BLOWER IS
LOCATED TO THE LEFT
OF THE BURNER SECTION,
AND CONDITIONED AIR IS
DISCHARGED TO THE RIGHT.
CAUTION
!
PERSONAL INJURY AND/OR PROPERTY DAMAGE
Improper use or installation of this furnace may cause premature
furnace component failure.
This furnace is not permitted to be used for heating of buildings under
construction.
WARNING
!
FIRE 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
ignition sources must be located at least 18 inches above the floor, see
Fig. 5. The furnace must be located or protected to avoid damage by
vehicles. When the furnace is installed in a public garage, airplane
hangar, or other building having a hazardous atmosphere, the furnace
must be installed in accordance with the NFGC.
18-IN. (457.2 mm)
MINIMUM TO BURNERS

58SU0A: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
6
Table 2 – Minimum Free Area Required for Each Combustion Air Opening or Duct to Outdoors
EXAMPLE: Determining Free Area
Table 3 – Minimum Space volumes for 100% combustion, Ventilation, and Dilution from Indoors
A02054
Fig. 6 – Prohibit Installation on Back
LOCATION RELATIVE TO COOLING EQUIPMENT
The cooling coil must be installed parallel with, or on the downstream
side of the unit to avoid condensation in the heat exchangers. When
installed parallel with the furnace, dampers or other flow control must
prevent chilled air from entering the furnace. If the dampers are
manually operated, they must be equipped with means to prevent
operation of either unit unless the damper is in the full-heat or full-cool
position.
AIR FOR COMBUSTION AND VENTILATION
Provisions for adequate combustion, ventilation, and dilution air must be
provided in accordance with:
• U.S. installations: Section 9.3 of the current edition of NFGC
NFPA54/ANSI Z223.1, Air for Combustion and Ventilation, and
applicable provisions of the local building codes.
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.
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 Area 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.
40,000 20 (12904) 5 (127) 14 (8696) 5 (127) 10 (6452) 4 (102)
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)
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 each Single Duct or Opening
80,000 + 30,000 = (110,000 divided by 2,000) = 55.0 Sq. In. for each two Horizontal Ducts
ACH*
*. Air Changes/Hour
OTHER THAN FAN-ASSISTED TOTAL
(1,000’S BTUH GAS INPUT RATE
FAN-ASSISTED TOTAL
(1,000’S BTUH GAS INPUT RATE)
30 40 50 40 60 80 100
Space Volume (ft.3)
0.60 1,050 1,400 1,750 1,000 1,500 2,000 3,300
0.50 1,260 1,680 2,100 1,200 1,800 2,400 3,960
0.40 1,575 2,100 2,625 1,500 2,250 3,000 4,950
0.30 2,100 2,800 3,500 2,000 3,000 4,000 6,600
0.20 3,150 4,200 5,250 3,000 4,500 6,000 9,900
0.10 6,300 8,400 10,500 6,000 9,000 12,000 19,800
0.00 NP NP NP NP NP NP NP
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. 6.
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
Carbon Monoxide Poisoning Hazard warning in venting section of
these instructions to determine if an adequate amount of make-up air is
available.

58SU0A: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
7
• Spaces having less than 50 cubic feet per 1,000 Btuh require the
OUTDOOR COMBUSTION AIR METHOD.
• Spaces having at least 50 cubic feet per 1,000 Btuh may use the
INDOOR COMBUSTION AIR, STANDARD or KNOWN AIR
INFILTRATION METHOD.
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. 7 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. 7 and Table 2.
*Minimum dimensions of 3 in. (76 mm).
NOTE: Use any of the following combinations of openings:
A&B, C&D, D&E, F&G
A03174
Fig. 7 – Air for Combustion, Ventilation, and Dilution from
Outdoors
c. TWO HORIZONTAL DUCTS require 1 square inch of free area
per 2,000 Btuh (1,100 mm2/kW) of combined input for all gas
appliances in the space per Fig. 7 and Table 2.
d. TWO OPENINGS OR VERTICAL DUCTS require 1 square
inch of free area per 4,000 Btuh (550 mm2/kW) for combined
input of all gas appliances in the space per Fig. 7 and Table 2.
3. ONE OUTDOOR OPENING requires:
a. 1 square inch of free area per 3,000 Btuh (734 mm2/kW) for
combined input of all gas appliances in the space per Table 2 and
b. Not less than the sum of the areas of all vent connectors in the
space.
The opening shall commence within 12” (300 mm) of the ceiling.
Appliances in the space shall have clearances of at least 1” (25 mm)
from the sides and back and 6” (150 mm) from the front. The opening
shall directly communicate with the outdoors or shall communicate
through a vertical or horizontal duct to the outdoors or spaces (crawl or
attic) that freely communicate with the outdoors.
Indoor Combustion Air - NFPA & AGA
Standard and Known-Air-Infiltration Rate Methods
Indoor air is permitted for combustion, ventilation, and dilution, if the
Standard or Known-Air-Infiltration Method is used.
*Minimum opening size is 100 in.2 with minimum dimensions of 3 in. (76 mm).
*Minimum of 3 in. (76 mm), when type -B1 vent is used.
A03175
Fig. 8 – Air for Combustion, Ventilation, and Dilution from Indoors
The Standard Method:
1. The space has no less volume than 50 cubic feet per 1,000 Btuh of
the maximum input ratings for all gas appliances installed in the
space and
2. The air infiltration rate is not known to be less than 0.40 air changes
per hour (ACH).
The Known Air Infiltration Rate Method shall be used, if the infiltration
rate is known to be:
1. Less than 0.40 ACH and
2. Equal to or greater than 0.10 ACH
Infiltration rates greater than 0.60 ACH shall not be used. The minimum
required volume of the space varies with the number of ACH and shall
be determined per Table 3 or Equations 1 and 2. Determine the minimum
required volume for each appliance in the space and add the volumes
together to get the total minimum required volume for the space.
Table 3 - Minimum Space Volumes were determined by using the
following equations from the current edition of 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:
A04002
2. For fan-assisted appliances such as this furnace:
A004003
1 SQ IN.
PER
4000
BTUH*
DUCTS
TO
OUTDOORS
1 SQ IN.
PER 4000
BTUH*
CIRCULATING
AIR DUCTS
VENT
THROUGH
ROOF
D
B
A
C
E
1 SQ IN.
PER 4000
BTUH*
DUCT
TO
OUTDOORS
CIRCULATING AIR DUCTS
1 SQ IN.
PER 2000
BTUH*
1 SQ IN.
PER 2000
BTUH*
DUCTS
TO
OUTDOORS
12″MAX
12″MAX
12″MAX
12″
MAX
12″
MAX
OUTDOORS
1 SQ IN.
PER
4000
BTUH*
F
G
CLEARANCE IN FRONT
OF COMBUSTION AIR
OPENINGS SHALL BE
AT LEAST 3 IN.
(305mm)
(305mm)
(305mm)
(305mm)
(305mm)
(76mm)
WARNING
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in death and/or personal
injury.
Many homes require air to be supplied from outdoors for furnace
combustion, ventilation, and dilution of flue gases. The furnace
combustion air supply must be provided in accordance with this
instruction manual.
CIRCULATING AIR
DUCTS
6" MIN
(FRONT)
Ü
CIRCULATING AIR DUCTS
VENT THROUGH ROOF
1 SQ IN.
PER 1000
BTUH* IN DOOR
ORWALL
12" MAX
1 SQ IN.
PER 1000
BTUH* IN DOOR
ORWALL
12" MAX
UNCONFINED
SPACE
INTERIOR
HEATED
SPACE
CLEARANCE IN FRONT OF COMBUSTION AIR
OPENINGS SHALL BE AT LEAST3 IN.
(305mm)
(152mm)
(305mm
)
Volume
Other
=21ft
3
ACH
I
other
1000 Btu/hr
Volume
Fan
=15ft
3
ACH
I
fan
1000 Btu/hr

58SU0A: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
8
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” (300 mm) of the ceiling and the second opening shall
commence within 12” (300 mm) of the floor. The minimum
dimension of air openings shall be at least 3 in. (80 mm), see
Fig. 8.
c. Combining space on different floor levels. The volumes of
spaces on different floor levels shall be considered as
communicating spaces if connected by one or more 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 adequate
permanent ventilation openings directly to outdoors having free
area of at least 1-in.2/4,000 Btuh of total input rating for all gas
appliances in the space.
3. In spaces that use the Indoor Combustion Air Method, infiltration
should be adequate to provide air for combustion, permanent
ventilation and dilution of flue gases. However, in buildings with
unusually tight construction, additional air MUST be provided
using the methods described in the Outdoor Combustion Air
Method section.
Unusually tight construction is defined as construction with:
a. Walls and ceilings exposed to the outdoors have a continuous,
sealed vapor barrier. Openings are gasketed or sealed and
b. Doors and openable windows are weatherstripped and
c. Other openings are caulked or sealed. These include joints
around window and door frames, between sole plates and floors,
between wall-ceiling joints, between wall panels, at penetrations
for plumbing, electrical and gas lines, etc.
Combination of Indoor and Outdoor Air
1. Indoor openings shall comply with the Indoor Combustion Air
Method below and,
2. Outdoor openings shall be located as required in the Outdoor
Combustion Air Method mentioned previously and,
3. Outdoor openings shall be sized as follows:
a. Calculate the Ratio of all Indoor Space volume divided by
required volume for Indoor Combustion Air Method below.
b. Outdoor opening size reduction Factor is 1 minus the Ratio in a.
above.
c. Minimum size of Outdoor openings shall be the size required in
Outdoor Combustion Air Method above multiplied by reduction
Factor in b. above. The minimum dimension of air openings shall
be not less than 3 in. (80 mm).
INSTALLATION
UPFLOW INSTALLATION
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in bottom
return-air opening. Remove and discard this panel when bottom return
air is used. To remove bottom closure panel, perform the following:
1. Tilt or raise furnace and remove two screws holding bottom filler
panel, see Fig. 9.
A10273
Fig. 9 – Removing Bottom Closure Panel
2. Rotate bottom filler panel downward to release holding tabs.
3. Remove bottom closure panel.
4. Reinstall bottom filler panel and screws.
Side Return Air Inlet
These furnaces are shipped with bottom closure panel installed in bottom
return-air opening. This panel MUST be in place when only side return
air is used.
NOTE: Side return-air openings can be used in UPFLOW and most
HORIZONTAL configurations. Do not use side return-air openings in
DOWNFLOW configuration.
Leveling Legs (If Desired)
In upflow position with side return inlet(s), leveling legs may be used,
see Fig. 10. Install field-supplied, 5/16 x 1-1/2 in. (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 Item 1. in Bottom
Return Air Inlet section.
To install leveling legs:
1. Position furnace on its back. Locate and drill a hole in each bottom
corner of furnace, see Fig. 10.
A89014
Fig. 10 – Leveling Legs
2. For each leg, install nut on bolt and then install bolt and nut in hole. (Install flat washer if desired.)
Bottom
Closure Panel
Bottom Filler Panel
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)

58SU0A: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
9
3. Install another nut on other side of furnace base. (Install flat washer
if desired.)
4. Adjust outside nut to provide desired height, and tighten inside nut
to secure arrangement.
5. Reinstall bottom closure panel if removed.
DOWNFLOW INSTALLATION
NOTE: For downflow applications, this furnace is approved for use on
combustible flooring when any one of the following 3 accessories are
used:
• Downflow combustible floor subbase
• Manufacturer’s approved Cased Coil
• Manufacturer’s approved Coil Casing
1. Determine application being installed from Table 4.
2. Construct hole in floor per Table 4 and Fig. 11.
3. Construct plenum to dimensions specified in Table 4 and Fig. 11.
4. If downflow subbase is used, install as shown in Fig. 12. If Coil or
Coil Casing, install as shown in Fig. 13.
NOTE: It is required that the perforated supply-air duct flanges be
completely folded over or removed from furnace when installing the
furnace on a factory-supplied cased coil or coil box. To remove the
supply-air duct flange, use wide duct pliers or hand seamers to bend
flange back and forth until it breaks off. Be careful of sharp edges, see
Fig. 14.
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in bottom
return-air opening. Remove and discard this panel when bottom return
air is used. To remove bottom closure panel, perform the following:
1. Tilt or raise furnace and remove two screws holding bottom filler
panel, see Fig. 9.
2. Rotate bottom filler panel downward to release holding tabs.
3. Remove bottom closure panel.
4. Reinstall bottom filler panel and screws
A96283
Fig. 11 – Floor and Plenum Opening Dimensions
A96285
Fig. 12 – Furnace, Plenum, and Subbase Installed
on a Combustible Floor
A08556
Fig. 13 – Furnace, Plenum, and Coil Assembly or
Coil Box Installed on a Combustible Floor
HORIZONTAL INSTALLATION
The furnace can be installed horizontally in an attic or crawl space on
either the left-hand (LH) or right-hand (RH) side. The furnace can be
hung from floor joists, rafters or trusses or installed on a
non-combustible platform, blocks, bricks or pad.
Suspended Furnace Support
The furnace may be supported under each end with threaded rod, angle
iron or metal plumber’s strap as shown, see Fig. 15 and Fig. 16. Secure
angle iron to bottom of furnace as shown. Heavy-gauge sheet metal
straps (plumber’s straps) may be used to suspend the furnace from each
bottom corner. To prevent screws from pulling out, use 2 #8 x 3/4-in. (19
mm) screws into the side and 2 #8 x 3/4-in. (19 mm) screws in the
bottom of the furnace casing for each strap, see Fig. 15 and Fig. 16. If
the screws are attached to ONLY the furnace sides and not the bottom,
the straps must be vertical against the furnace sides and not pull away
from the furnace sides, so that the strap attachment screws are not in
tension (are loaded in shear) for reliable support.
PLENUM
OPENING
C
A
BD
FLOOR
OPENING
WARNING
!
FIRE, EXPLOSION, AND CARBON MONOXIDE
POISONING 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.
DOWNFLOW
SUBBASE
SHEET METAL
PLENUM
FLOOR
OPENING
FURNACE
(OR COIL CASING
WHEN USED)
COMBUSTIBLE
FLOORING
APPROVED
COIL ASSEMBLY
OR
COIL BOX
FURNACE
SHEET METAL
PLENUM
FLOOR
OPENING
COMBUSTIBLE
FLOORING

58SU0A: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
10
Table 4 – Opening Dimensions - In. (mm)
Platform Furnace Support
Construct working platform at location where all required furnace
clearances are met, see Fig. 2 and Fig. 17. For furnaces with 1-in. (25
mm) clearance requirement on side, set furnace on noncombustible
blocks, bricks or angle iron. For crawl space 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.
Roll-Out Protection
Provide a minimum 17-3/4 in. x 22 in. (451 mm x 559 mm) piece of
sheet metal for flame roll-out protection in front of burner area for
furnaces closer than 12 inches (305 mm) above the combustible deck or
suspended furnaces closer than 12 inches (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. 17 for proper orientation of
roll-out shield.
Bottom Return Air Inlet
These furnaces are shipped with bottom closure panel installed in bottom
return-air opening. Remove and discard this panel when bottom return
air is used. To remove bottom closure panel, perform the following:
1. Tilt or raise furnace and remove two screws holding bottom filler
panel, see Fig. 9.
2. Rotate bottom filler panel downward to release holding tabs.
3. Remove bottom closure panel.
4. Reinstall bottom filler panel and screws. Side Return Air Inlet
Side Return Air Inlet
These furnaces are shipped with bottom closure panel installed in bottom
return-air opening. This panel MUST be in place when side return air
inlet(s) is used without a bottom return air inlet.
FILTER ARRANGEMENT
There are no provisions for an internal filter rack in these furnaces.
A field-supplied accessory external filter is required.
Refer to the instructions supplied with the external filter rack for
assembly and installation options.
AIR DUCTS
General Requirements
The duct system should be designed and sized according to accepted
national standards such as those published by: Air Conditioning
Contractors Association (ACCA), Sheet Metal and Air Conditioning
Contractors National Association (SMACNA) or American Society of
Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) or
consult The Air Systems Design Guidelines reference tables available
from your local distributor. The duct system should be sized to handle
the required system design CFM at the design external static pressure.
The furnace airflow rates are provided in Table 5 - AIR
DELIVERY-CFM (with filter).
When a furnace is installed so that the supply ducts carry air circulated
by the furnace to areas outside the space containing the furnace, the
return air shall also be handled by duct(s) sealed to the furnace casing
and terminating outside the space containing the furnace.
Secure ductwork with proper fasteners for type of ductwork used. Seal
supply- and return-duct connections to furnace with code approved tape
or duct sealer.
NOTE: Flexible connections should be used between ductwork and
furnace to prevent transmission of vibration. Ductwork passing through
unconditioned space should be insulated and sealed to enhance system
performance. When air conditioning is used, a vapor barrier is
recommended.
Maintain a 1-in. (25 mm) clearance from combustible materials to
supply air ductwork for a distance of 36 in. (914 mm) horizontally from
the furnace. See NFPA 90B or local code for further requirements.
Ductwork Acoustical Treatment
NOTE: Metal duct systems that do not have a 90 degree elbow and 10
ft. (3 M) of main duct to the first branch take-off may require internal
acoustical lining. As an alternative, fibrous ductwork may be used if
constructed and installed in accordance with the latest edition of
SMACNA construction standard on fibrous glass ducts. Both acoustical
lining and fibrous ductwork shall comply with NFPA 90B as tested by
UL Standard 181 for Class 1 Rigid air ducts.
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 airstream. The
cover attachment shall prevent leaks.
FURNACE
CASING
WIDTH
APPLICATION
PLENUM OPENING FLOOR OPENING
A B C D
17–1/2
(445)
Upflow Applications on Combustible or Noncombustible Flooring
(subbase not required)
16
(406)
21-5/8
(549)
16-5/8
(422)
22-1/4
(565)
Downflow Applications on Noncombustible Flooring (subbase not
required)
15-7/8
(403)
19
(483)
16-1/2
(419)
19-5/8
(498)
Downflow applications on combustible flooring (subbase required) 15-1/8
(384)
19
(483)
16-3/4
(425)
20-5/8
(600)
Downflow Applications on Combustible Flooring with Coil Assembly or
coil box (subbase not required)
15-1/2
(394)
19
(483)
16-1/2
(419)
20
(508)
21
(533)
Upflow Applications on Combustible or Noncombustible Flooring
(subbase not required)
19-1/2
(495)
21-5/8
(549)
20-1/8
(511)
22-1/4
(565)
Downflow Applications on Noncombustible Flooring (subbase not
required)
19-3/8
(492)
19
(483)
20
(508)
19-5/8
(498)
Downflow applications on combustible flooring subbase required) 18-5/8
(473)
19
(483)
20-1/4
(514)
20-5/8
(600)
Downflow Applications on Combustible Flooring with Coil Assembly or
coil box (subbase not required)
19
(483)
19
(483)
20
(508)
20
(508)
WARNING
!
CARBON MONOXIDE AND POISONING
HAZARD
Failure to follow this warning could result in personal injury, or death.
Never operate a furnace without a filter or with filter access door
removed.