YM8M-YMLM-MP
INSTALLATION MANUAL
RESIDENTIAL GAS FURNACE
WITH PSC MOTOR
MODELS:
TM8M/TMLM*MP, YM8M/YMLM*MP,
CM8M/CMLM*MP, LM8M/LMLM*MP
(80% Modulating Multi-position / Low NOx)
LIST OF SECTIONS
SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
DUCTWORK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
GAS PIPING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
ELECTRICAL POWER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
TWINNING AND STAGING . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
VENT SYSTEM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
LIST OF FIGURES
Duct Attachment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Vertical Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Coil Flange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Horizontal Right Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Horizontal Left Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
PC Series Upflow Coil Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Horizontal Left or Right application (Right Shown) . . . . . . . . . . . . . . 8
Combustible Floor Base Accessory . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Horizontal Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Typical Attic Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Typical Suspended Furnace / Crawl Space Installation . . . . . . . . . . . 9
Downflow Venting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Downflow Installation - Gas Valve Rotation . . . . . . . . . . . . . . . . . . . . 9
Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Side Return Cutout Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Gas Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Upflow/Downflow Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Horizontal Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Electrical Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
LIST OF TABLES
Unit Clearances to Combustibles . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Coil Projection Dimensions - PC Series Coils . . . . . . . . . . . . . . . . . . 6
Cabinet and Duct Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Recommended Filter Sizes (High Velocity 600 FPM) . . . . . . . . . . . . 8
High Altitude Orifices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Ratings & Physical / Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . 10
Estimated Free Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
START-UP AND ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . 20
SAFETY CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
NORMAL OPERATION AND DIAGNOSTICS . . . . . . . . . . . . . 25
REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . 27
REPLACEMENT PART CONTACT INFORMATION . . . . . . . . 27
WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Thermostat Chart - Single Stage Air Conditioner –
Variable Speed or PSC Modulating Furnace . . . . . . . . . . . . . . . . . .14
Thermostat Chart - Two Stage Air Conditioner –
Variable Speed or PSC Modulating Furnace . . . . . . . . . . . . . . . . . .15
Thermostat Chart - Two Stage Air Conditioner with Single Stage
Thermostat – Variable Speed or PSC Modulating Furnace . . . . . . .16
Thermostat Chart - Single Stage Heat Pump –
Variable Speed or PSC Modulating Furnace . . . . . . . . . . . . . . . . . .17
Thermostat Chart - Single Stage Heat Pump –
Variable Speed or PSC Modulating Furnace . . . . . . . . . . . . . . . . . .18
Thermostat Chart - Two Stage Heat Pump –
Variable Speed or PSC Modulating Furnace . . . . . . . . . . . . . . . . . .19
Combustion Air Inducer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Combustion Airflow Path Through The Furnace
Casing to the Burner Compartment . . . . . . . . . . . . . . . . . . . . . . . . .20
Outside and Ambient Combustion Air . . . . . . . . . . . . . . . . . . . . . . . .21
Gas Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Furnace Control Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Unconfined Space Minimum Area in Square Inch . . . . . . . . . . . . . .19
Free Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Gas Rate (CU FT/HR) at Full Input . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Inlet Gas Pressure Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Nominal Manifold Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Cooling Airflow - A/C Capacity in Tons . . . . . . . . . . . . . . . . . . . . . . .24
EFFICIENCY
RATING
CERTIFIED
ISO 9001
Certified Quality
Management System
These high efficiency, compact units employ induced combustion, reliable hot surface ignition and high heat transfer aluminized tubular heat
exchangers. The units are factory shipped for installation in upflow or
horizontal applications and may be converted for downflow applications.
These furnaces are designed for residential installation in a basement,
closet, alcove, attic, recreation room or garage and are also ideal fo r
commercial applications. All units are factory assembled, wired and
tested to assure safe dependable and economical installation and operation.
These units are Category I listed and may be common vented with
another gas appliance as allowed by the National Fuel Gas Code.
SECTION I: SAFETY
This is a safety alert symbol. When you see this symbol on
labels or in manuals, be alert to the potential for personal
injury.
Understand and pay particular attention to the signal words DANGER,
WARNING, or CAUTION.
DANGER indicates an imminently hazardous situation, which, if not
avoided, will result in death or serious injury
WARNING indicates a potentially hazardous situation, which, if not
avoided, could result in death or serious injury
CAUTION indicates a potentially hazardous situation, which, if not
avoided may result in m inor or moderate injury.
alert against unsafe practices and hazards involving only property damage.
Improper installation may create a condition where the operation of
the product could cause personal injury or property damage.
Improper installation, adjustment, alteration, service or maintenance can cause injury or property damage. Failure to carefully
read and follow all instructions in this manual can result in furnace malfunction, death, personal injury and/or property damage. Only a qualifie d contractor, installer or service agency should
install this product.
.
.
It is also used to
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368261-UIM-A-0508
SPECIFIC SAFETY RULES AND PRECAUTIONS
1. Only Natural gas or Propane (LP) gas are approved for use with
this furnace.
2. Install this furnace only in a location and position as specified in
these instructions.
3. A gas-fired furnace for installation in a residential garage must be
installed as specified in these instructions.
4. Provide adequate combustion and ventilation air to the furnace
space as specified in these instructions.
5. Combustion products must be discharged outdoors. Connect this
furnace to an approved vent system only, as specified in SECTION VII of these instructions.
6. Test for gas leaks as specified in these instructions.
FIRE OR EXPLOSION HAZARD
Failure to follow the safety warnings exactly could result in serious
injury, death or property damage.
Never test for gas leaks with an open flame. Use a commercially
available soap solution made specifically for detection of leaks to
check all connections. A fire or explosion may result causing property damage, personal injury or loss of life.
7. Always install the furnace to operate within the furnace’s intended
temperature rise range. Only connect the furnace to a duct system
which has an external static pressure within the allowable range,
as specified on the furnace rating plate.
8. 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.
9. It is permitted to use the furnace for heating of buildings or structures under construction where the application and use must comply with all manufacturer’s installation instructions including:
• Proper vent installation;
• Furnace operating under thermostatic control;
• Return air duct sealed to the furnace;
• Air filters in place;
• Set furnace input rate and temperature rise per rating plate
marking;
• Means for providing outdoor air required for combustion;
• Return air temperature maintained between 55ºF (13ºC) and
80ºF (27ºC);
• The air filter must be replaced upon substantial completion of
the construction process;
• Clean furnace, duct work and components upon substantial
completion of the construction process, and verify furnaceoperating conditions including ignition, input rate, temperature
rise and venting, according to the manufacturer’s instructions.
10. When installed in a Non-HUD-Approved Modular Home or building
constructed on-site, combustion air shall not be supplied from
occupied spaces.
11. The size of the unit should be based on an acceptable heat loss
calculation for the structure. ACCA, Manual J or other approved
methods may be used.
SAFETY REQUIREMENTS
This product must be installed in strict compliance with the installation instructions and any applicable local, state, and national codes
including, but not limited to building, electrical, and mechanical
codes.
• Refer to the unit rating plate for the furnace model number, and
then see the dimensions page of this instruction for return air plenum dimensions in Figure 14, "Dimensions". The plenum must be
installed according to the instructions.
• Provide clearances from combustible materials as listed under
Clearances to Combustibles.
• Provide clearances for servicing ensuring that service access is
allowed for both the burners and blower.
• These models ARE NOT
into a HUD Approved Modular Home
(Mobile) Home.
• This furnace is not approved for installation in trailers or recreational vehicles.
• Furnaces for installation on combustible flooring shall not be
installed directly on carpeting, tile or other combustible material
other than wood flooring.
• Check the rating plate and power supply to be sure that the electrical characteristics match. All models use nominal 115 VAC, 1
Phase, 60-Hertz power supply. DO NOT CONNECT THIS APPLIANCE TO A 50 HZ POWER SUPPLY OR A VOLTAGE ABOVE
130 VOLTS.
• Furnace shall be installed so the electrical components are protected from water.
• Installing and servicing heating equipment can be hazardous due
to the electrical components and the gas fired components. Only
trained and qualified personnel should install, repair, or service
gas heating equipment. Untrained service personnel can perform
basic maintenance functions such as cleaning and replacing the
air filters. When working on heating equipment, observe precautions in the manuals and on the labels attached to the unit and
other safety precautions that may apply.
CSA listed or approved for installation
or a Manufactured
COMBUSTION AIR QUALITY
(LIST OF CONTAMINANTS)
The furnace requires OUTDOOR AIR for combustion when the furnace
is located in any of the following environments.
• Restricted Environments
• Commercial buildings
• Buildings with indoor pools
• Furnaces installed in laundry rooms
• Furnaces installed in hobby or craft rooms
• Furnaces installed near chemical storage areas
• Chemical exposure
The furnace requires OUTDOOR AIR for combustion when the furnace
is located in an area where the furnace is being exposed to the following substances and / or chemicals.
• 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
When outdoor air is used for combustion, the combustion air intake duct
system termination must be located external to the building and in an
area where there will be no exposure to the substances listed above.
2 Johnson Controls Unitary Products
The furnace area must not be used as a broom closet or for any
other storage purposes, as a fire hazard may be created. Never
store items such as the following on, near or in contact with the furnace.
1. Spray or aerosol cans, rags, brooms, dust mops, vacuum
cleaners or other cleaning tools.
2. Soap powders, bleaches, waxes or other cleaning compounds; plastic items or containers; gasoline, kerosene, cigarette lighter fluid, dry cleaning fluids or other volatile fluid.
3. Paint thinners and other painting compounds.
4. Paper bags, boxes or other paper products
Never operate the furnace with the blower door removed. To
do so could result in serious personal injury and/or equipment
damage.
CODES AND STANDARDS
Follow all national, local codes and standards in addition to this installation manual. The installation must comply with regulations of the serving gas supplier, local building, heating, plumbing, and other codes. In
absence of local codes, the installation must comply with the national
codes listed below and all authorities having jurisdiction.
In the United States and Canada, follow all codes and standards for the
following, using the latest edition available:
STEP 1 -Safety
• 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
• CANADA: CAN/CGA-B149.1 National Standard of Canada. Natural Gas and Propane Installation Codes (NSCNGPIC)
STEP 2 -General Installation
• US: Current edition of the NFGC and 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. Capital, N.W.
Washington DC 20001
or www.NFPA.org
• CANADA: NSCNGPIC. For a copy contact:
Standard Sales, CSA International
178 Rexdale Boulevard
Etobicoke, (Toronto) Ontario Canada M9W 1RS
STEP 3 -Combustion and Ventilation Air
• US: Section 5.3 of the NFGC, air for Combustion and Ventilation
• CANADA: Part 7 of NSCNGPIC, Venting Systems and Air Supply
for Appliances
STEP 4 -Duct Systems
• US and CANADA: Air Conditioning Contractors Association
(ACCA) Manual D, Sheet Metal and Air Conditioning Contractors
Association National Association (SMACNA), or American Society of Heating, Refrigeration, and Air Conditioning Engineers
(ASHRAE) 1997 Fundamentals Handbook Chapter 32.
STEP 5 -Acoustical Lining and Fibrous Glass Duct
• US and CANADA: Current edition of SMACNA and NFPA 90B as
tested by UL Standard 181 for Class I Rigid Air Ducts
STEP 6 -Gas Piping and Gas Pipe Pressure Testing
• US: NFGC; chapters 2, 3, 4, & 9 and National Plumbing Codes
• CANADA: NSCNGPIC Part 5
STEP 7 -Electrical Connections
• US: National Electrical Code (NEC) ANSI/NFPA 70
• CANADA: Canadian Electrical Code CSA C22.1
368261-UIM-A-0508
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 who have not kept up with changing residential and non-HUD
modular home construction practices. These instructions are required
as a minimum for a safe installation.
FOR FURNACES INSTALLED IN THE COMMONWEALTH OF MASSACHUSETTS ONLY
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 lo cal 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.
INSPECTION
As soon as a unit is received, it should be inspected for possib le damage during transit. If damage is evident, the extent of the damage
should be noted on the carrier’s freight bill. A separate request for
inspection by the carrier’s agent should be made in writing. Also, before
installation, the unit should be checked for screws or bolts which may
have loosened in transit. There are no shipping or spacer brackets
which need to be removed from the interior of this unit.
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368261-UIM-A-0508
FURNACE LOCATION AND CLEARANCES
The furnace shall be located using the following guidelines:
1. Where a minimum amount of air intake/vent piping and elbows will
be required.
2. As centralized with the air distribution as possible.
3. Where adequate combustion air will be available.
4. Where it will not interfere with proper air circulation in the confined
space.
5. Where the outdoor vent terminal will not be blocked or restricted.
Refer to “VENT CLEARANCES” located in SECTION VII of these
instructions. These minimum clearances must be maintained in
the installation.
6. Where the unit will be installed in a level position with no more than
1/4” (6.4 mm) slope side-to-side and front-to-back.
Installation in freezing temperatures:
1. Furnace shall be installed in an area where ventilation facilities
provide for safe limits of ambient temperature under normal operating conditions.
Table 1: Unit Clearances to Combustibles (All Dimensions in Inches, and All Surfaces Identified with the Unit in an Upflow Configuration)
Application
Upflow B-Vent 1 (2.5) 3 (7.6) 0 (0.0) 0 (0.0) 0 (0.0) 1 (2.5) Combustible Yes Yes Yes No
Downflow B-Vent 1 (2.5) 3 (7.6) 0 (0.0) 0 (0.0) 0 (0.0) 1 (2.5)
Horizontal B-Vent 1 (2.5) 3 (7.6) 0 (0.0) 0 (0.0) 0 (0.0) 1 (2.5) Combustible No Yes Yes
1.Special floor base or air conditioning coil required for use on combustible floor.
2.Line contact only permitted between lines formed by the intersection of the rear panel and side panel (top in horizontal position) of the furnace jacket and building
joists, studs or framing.
Top Front Rear Left Side Right Side Flue
In. (cm) In. (cm) In. (cm) In. (cm) In. (cm) In. (cm)
SECTION II: DUCTWORK
DUCTWORK GENERAL INFORMATION
The duct system’s design and installation must:
1. Handle an air volume appropriate for the served space and within
the operating parameters of the furnace specifications.
2. Be installed in accordance of National Fire Protection Association
as outlined in NFPA standard 90B (latest editions) or applicable
national, provincial, state, and local fire and safety codes.
3. Create a closed duct system. For residential and Non-HUD Modular Home installations, when a furnace is installed so that the supply ducts carry air circulated by the furnace to areas outside the
space containing the furnace, the return air shall also be handled
by a duct(s) sealed to the furnace casing and terminating outside
the space containing the furnace.
4. Complete a path for heated or cooled air to circulate through the
air conditioning and heating equipment and to and from the conditioned space.
The cooling coil must be installed in the supply air duct, downstream of the furnace. Cooled air may not be passed over the heat
exchanger.
When the furnace is used with a cooling coil, the coil must be installed
parallel with, or in the supply air side of the furnace to avoid condensation in the primary heat exchanger. When a parallel flow arrangement is
used, dampers or other means used to control airflow must be adequate to prevent chilled air from entering the furnace. If manually operated, the damper must be equipped with means to prevent the furnace
or the air conditioner from operating unless the damper is in full heat or
cool position.
2. Do not allow return air temperature to be below 55º F (13° C) for
extended periods. To do so may cause condensation to occur in
the main heat exchanger, leading to premature heat exchanger
failure.
Clearances for access/service:
Ample clearances should be provided to permit easy access to the unit.
The following minimum clearances are recommended:
1. Twenty-four (24) inches (61 cm) between the front of the furnace
and an adjacent wall or another appliance, when access is
required for servicing and cleaning.
2. Eighteen (18) inches (46 cm) at the side where access is required
for passage to the front when servicing or for inspection or replacement of flue/vent connections.
In all cases, accessibility clearances shall take precedence over clearances for combustible materials where accessibility clearances are
greater.
Installation in a residential garage:
A gas-fired furnace for installation in a residential garage must be
installed so the burner(s) and the ignition source are located not less
than 18 inches (46 cm) above the floor, and the furnace must be located
or protected to avoid physical damage by vehicles.
Floor/
Bottom
1 (25.4)
When replacing an existing furnace, if the existing plenum is not the
same size as the new furnace then the existing plenum must be
removed and a new plenum installed that is the proper size for the new
furnace. If the plenum is shorter than 12” (30.5 cm) the turbulent air flow
may cause the limit controls not to operate as designed, or the limit controls may not operate at all.
The duct system is a very important part of the installation. If the duct
system is improperly sized the furnace will not operate properly.
The ducts attached to the furnace plenum, should be of sufficient size
so that the furnace operates at the specified external static pressure
and within the air temperature rise specified on the nameplate.
The minimum plenum height is 12” (30.5 cm). The furnace will not
operate properly on a shorter plenum height. The minimum recommended rectangular duct height is 4 inches (10 cm) attached to the
plenum.
If a matching cooling coil is used, it may be placed directly on the furnace outlet and sealed to prevent leakage. If thermoplastic evaporator
‘A’ coil drain pans are to be installed in the upflow/horizontal configuration, then extra 2” minimum spacing may be needed to ensure against
drain pan distortion.
The duct system must be properly sized to obtain the correct airflow
for the furnace size that is being installed.
Refer to Table6, "Ratings & Physical / Electrical Data" or the furnace rating plate for the correct rise range and static pressures.
If the ducts are undersized, the result will be high duct static pressures and/or high temperature rises which can result in a heat
exchanger OVERHEATING CONDITION. This condition can result
in premature heat exchanger failure, which can result in personal
injury, property damage, or death.
Closet Alcove Attic
1
Yes Yes Yes No
Line
Contact
Yes
2
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368261-UIM-A-0508
DUCT FLANGES
Four flanges are provided to attach ductwork to the furnace. These
flanges are rotated down for shipment. In order to use the flanges,
remove the screw holding an individual flange, rotate the flange so it is
in the upward position and reinstall the screw then repeat this for all 4
flanges.
If the flanges are not used, they should remain in the rotated down position as shipped.
For duct attachment,
if needed.
Factory
installed
FIGURE 1: Duct Attachment
DUCTWORK INSTALLATION AND SUPPLY PLENUM
CONNECTION - UPFLOW/HORIZONTAL
Attach the supply plenum to the furnace outlet. The use of
an approved flexible duct connector is recommended on all
installations. This connection should be sealed to prevent
air leakage. The sheet metal should be crosshatched to
eliminate any popping of the sheet metal when the indoor
fan is energized.
FLOOR BASE AND DUCTWORK INSTALLATION DOWNFLOW
Installations on combustible material or directly on any
floors must use a combustible floor base shown in Figure 8,
"Combustible Floor Base Accessory". Follow the instructions supplied with the combustible floor base accessory.
This combustible floor base can be replaced with a matching cooling coil, properly sealed to prevent leaks. Follow the
instructions supplied with the cooling coil cabinet for installing the cabinet to the duct connector. Plug intake and vent
pipe holes in bottom panel and move grommet to desired
vent side exit.
Downflow Air Conditioning Coil Cabinet
The furnace should be installed with coil cabinet part number specifically intended for downflow application. If a matching cooling coil is
used, it may be placed directly on the furnace outlet and sealed to prevent leakage. For details of the coil cabinet dimensions and installation
requirements, refer to the installation instructions supplied with the coil
cabinet.
Attach the air conditioning coil cabinet to the duct connector, and then
position the furnace on top of the coil cabinet. The connection to the furnace, air conditioning coil cabinet, duct connector, and supply air duct
must be sealed to prevent air leakage.
COIL INSTALLATION
COIL/FURNACE ASSEMBLY - MC/FC/PC SERIES
COILS
Furnace
Furnace
UPFLOW
DOWNFLOW
FIGURE 2: Vertical Applications
FURNACE ASSEMBLY - MC & FC SERIES COILS
These coils are factory shipped for installation in either upflow or downflow applications with no conversion.
Position the coil casing over or under the furnace opening as shown in
Figure 2, "Vertical Applications" after configuring coil flanges as
required see “Coil Flange” section below.
COIL FLANGE INSTALLATION
The coils include removable flanges to allow proper fit up with furnaces
having various inlet and outlet flange configurations. The two flanges
are attached to the top of the coil in the factory during production. For
proper configuration of flanges refer to Figure 3, "Coil Flange".
FACTORY
FLANGE
LOCATION
(Used for upflow
or horizontal
ALTERNATE
FLANGE LOCATION
(Used for downflow or
horizontal left installations)
right installations)
FIGURE 3: Coil Flange
FURNACE ASSEMBLY - MC SERIES COILS ONLY
MC coils are supplied ready to be installed in a horizontal position. A
horizontal pan is factory installed. MC coils should be installed in all horizontal applications with the horizontal drain pan side down.
On all installations without a coil, a removable access panel is rec-
Mounting Plate
ommended in the outlet duct such that smoke or reflected light
would be observable inside the casing to indicate the presence of
leaks in the heat exchanger. This access cover shall be attached in
such a manner as to prevent leaks.
Furnace
FIGURE 4: Horizontal Right Application
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368261-UIM-A-0508
For horizontal left hand applications no conversion is required to an MC
coil when used with a downflow/horizontal furnace. A mounting plate,
supplied with every coil should always be installed on the side designated as top side. See Figures 4 & 5.
Mounting Plate
Furnace
FIGURE 5: Horizontal Left Application
FURNACE ASSEMBLY - PC SERIES COILS
These upflow coils are designed for installation on top of upflow furnaces only.
If the coil is used with a furnace of a different size, use a 45° transition
to allow proper air distribution through the coil.
1. Position the coil casing over the furnace opening as shown in Figure 6, "PC Series Upflow Coil Installation".
2. Place the ductwork over the coil casing flange and secure.
3. Check for air leakage between the furnace and coil casing and
seal appropriately.
Do not drill any holes or drive any screws into the front duct
flange on the coil in order to prevent damaging coil tubing. See
Figure 6, "PC Series Upflow Coil Installation"
C
(Min)
D
CRITICAL COIL PROJECTION
The coil assembly must be located in the duct such that a minimum distance is maintained between the top of the coil and the top of the duct.
Refer to Table 2, "Coil Projection Dimensions - PC Series Coils".
COIL / FURNACE ASSEMBLY - HC SERIES COILS
These coils are supplied ready to be installed in a right hand position or
a left hand position. When used in conjunction with a horizontal furnace
(blow through) application, the coil should be oriented with the opening
of the “A” coil closest to the furnace. See Figures 7.
NOTE: Each coil is shipped with an external tie plate that should be
used to secure the coil to the furnace. It should be installed on the back
side of the coil using the dimpled pilot holes. See Figures 7.
Use tie plate
supplied with coil
Gas Furnace
Air flow
FIGURE 7: Horizontal Left or Right application (Right Shown)
DOWNFLOW DUCT CONNECTORS
All downflow installations must use a suitable duct connector approved
by the furnace manufacturer for use with this furnace. The duct connectors are designed to be connected to the rectangular duct under the
floor and sealed. Refer to the instructions supplied with the duct connector for proper installation. Refer to the separate accessory parts list
at the end of these instructions for the approved accessory duct connectors.
Flexible
Duct Collar
Field
Fabricated
Ductwork
Upflow
Coil
Upflow
Furnace
Primary
Drain
Secondary
Drain
Do not drill
or Screw
this flange
Alternate
Drain Location
FIGURE 6: PC Series Upflow Coil Installation
Table 2: Coil Projection Dimensions - PC Series Coils
COIL SIZE DIMENSION “C” INCH
PC18 3-1/2
PC24 4-1/2
PC30, PC32, PC35 4-1/2
PC42, PC43, PC36, PC37 5-1/2
PC48 6-1/2
PC60 9
NOTE: Dimension “C” should be at least 2/3 of dimension “D”. See Figure 6, "PC Series Upflow Coil Installation"
FURNACE
WARM AIR PLENUM
WITH 1” FLANGES
FIBERGLASS
INSULATION
FIBERGLASS TAPE
UNDER FLANGE
COMBUSTIBLE FLOOR
BASE ACCESSORY
FIGURE 8: Combustible Floor Base Accessory
RESIDENTIAL AND MODULAR HOME UPFLOW
RETURN PLENUM CONNECTION
Return air may enter the furnace through the side(s) or bottom depending on the type of application. Return air may not be connected into the
rear panel of the unit.
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BOTTOM RETURN AND ATTIC INSTALLATIONS
Bottom return applications normally pull return air through a base platform or return air plenum. Be sure the return platform structure or return
air plenum is suitable to support the weight of the furnace.
The internal bottom panel must be removed for this application.
Attic installations must meet all minimum clearances to combustibles
and have floor support with required service accessibility.
HORIZONTAL APPLICATION
FIGURE 9: Horizontal Application
This furnace may be installed in a horizontal position on either side
as shown above. It must not be installed on its back.
368261-UIM-A-0508
When a furnace is installed in an attic or other insulated space,
keep all insulating materials at least 12 inches (30.5 cm) away from
furnace and burner combustion air openings.
SUSPENDED FURNACE / CRAWL SPACE
INSTALLATION
The furnace can be hung from floor joists or installed on suitable blocks
or pad. Blocks or pad installations shall provide adequate height to
ensure the unit will not be subject to water damage. Units may also be
suspended from rafters or floor joists using rods, pipe angle supports or
straps. Angle supports should be placed at the supply air end and near
the blower deck. Do not support at return air end of unit. All four suspension points must be level to ensure quite furnace operation. When
suspending the furnace use a secure platform constructed of plywood
or other building material secured to the floor joists. Refer to for typical
crawl space installation.
ATTIC INSTALLATION
Line contact only permissible
between lines formed by the
intersection of furnace top
and two sides and building
joists, studs or framing
Filter rack
must be a minimum
distance
of 18” (45.7 cm)
from the
furnace
Return
Air
Gas Piping
Sediment
Trap
30” MIN.
Work Area
FIGURE 10: Typical Attic Installation
This appliance is certified for line contact when the furnace is installed
in the horizontal left or right position. The line contact is only permissible
between lines that are formed by the intersection of the top and two
sides of the furnace and the building joists, studs or framing. This line
may be in contact with combustible material. Refer to Figure 10, "Typical Attic Installation".
12”
12”
Supply
Air
Vent (Maintain
required
clearances to
combustibles)
Sheet metal in
front of furnace
combustion air
Openings is
Recommended
Angle Iron
Bracket
6” Min. Between
Rod & Front of Furnace
1” Max. Between
Rod & Back of Furnace
Support
Bracket
FIGURE 11: Typical Suspended Furnace / Crawl Space Installation
DOWNFLOW APPLICATION
To apply the furnace in a downflow position, it will be necessary to
rotate the vent blower 90° left or right so that the vent pipe passes
through the side of the furnace casing rather than the end. See Figure
12, "Downflow Venting".
For modulating furnaces to be used in the downflow position, it is
necessary to rotate the gas valve so that it is upright when the furnace is installed. Loosen the pipe union between the gas valve and
manifold, rotate the valve as far upward as it will go, and tighten the
union. See Figure 13, "Downflow Installation - Gas Valve Rotation".
For downflow
installation,rotate
Rotate vent
blower 90°
gas valve upwards,
as shown
either way
LEFT SIDE VENT
RIGHT SIDE VENT
FIGURE 12: Downflow Venting FIGURE 13: Downflow Installation - Gas Valve Rotation
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LEFT SIDE
(For Cladded door add
appoximately an additional .75”)
.5”
B
.5”
24.38”
SUPPLY END
20”
28.5”
29.5”
Vent
Outlet
Electrical
Entry
Gas Pipe
Entry
Thermostat
Wiring
Vent
Outlet
C
FRONT
A
33”
Electrical
Entry
Vent Outlet
Gas Pipe
Entry
Thermostat
Wiring
B
RIGHT SIDE
23”
24.25”
RETURN END
FIGURE 14: Dimensions
Table 3: Cabinet and Duct Dimensions
BTUH (kW)
Input
Nominal
CFM (m
3
/min)
Cabinet
Size
AA (cm)BB (cm)CC (cm) Lbs
Cabinet Dimensions (Inches)
60 (17.6) 1200 (34.0) A 14 1/2 36.8 13 1/2 34.3 10.3 26.2 94
80 (23.4) 1200 (34.0) B 17 1/2 44.4 16 1/2 41.9 11.8 29.9 103
80 (23.4) 1600 (45.3) C 21 53.3 20 50.8 13.6 34.5 114
100 (29.3) 1600 (45.3) C 21 53.3 20 50.8 13.6 34.5 118
100 (29.3) 2000 (56.6) C 21 53.3 20 50.8 13.6 34.5 122
120 (35.1) 2000 (56.6) C 21 53.3 20 50.8 15.8 40.1 129
14”
1.5”
.5”
1”
.5”
Approximate
Operating Weights
SECTION III: FILTERS
FILTER INSTALLATION
All applications require the use of a field installed filter. All filters and
mounting provision must be field supplied.
Filters must be installed external to the furnace cabinet. DO NOT
attempt to install filters inside the furnace.
Table 4: Recommended Filter Sizes (High Velocity 600 FPM)
CFM
(m³/min)
1200 (34.0) A 16 x 25 14 x 25
1200 (34.0) B 16 x 25 16 x 25
1600 (45.3) C 16 x 25 20 x 25
2000 (56.6) C (2) 16 x 25 20 x 25
NOTES:
1.Air velocity through throwaway type filters may not exceed 300 feet per
minute (91.4 m/min). All velocities over this require the use of high velocity
filters.
2.Do not exceed 1800 CFM using a single side return and a 16x25 filter. For
CFM greater than 1800, you may use two side returns or one side and the
bottom or one side return with a transition to allow use of a 20x25 filter.
Cabinet
Size
Side
(in)
Bottom
(in)
SIDE RETURN
Locate the “L” shaped corner locators. These indicate the size of the cutout to be made in the furnace side panel. Refer to Figure 15, "Side
Return Cutout Markings".
Front of
Furnace
Side of
Furnace
Corner
Markings
FIGURE 15: Side Return Cutout Markings
Install the side filter rack following the instructions provided with that
accessory. If a filter(s) is provided at another location in the return air
system, the ductwork may be directly attached to the furnace side
panel.
Some accessories such as electronic air cleaners and pleated
media may require a larger side opening. Follow the instructions
supplied with that accessory for side opening requirements. Do not
cut the opening larger than the dimensions shown in Figure 14,
"Dimensions".
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368261-UIM-A-0508
HORIZONTAL APPLICATION
Horizontal Filters
All filters and mounting provision must be field supplied. All installations must have a filter installed.
Any branch duct (rectangular or round duct) attached to the plenum
must attach to the vertical plenum before the filter. The use of straps
and / or supports is required to support the weight of the external filte r
box.
Downflow Filters
Downflow furnaces typically are installed with the filters located above
the furnace, extending into the return air plenum or duct. Any branch
duct (rectangular or round duct) attached to the plenum must attach to
the vertical plenum above the filter height.
Filter(s) may be located in the duct system external to the furnace using
an external duct filter box attached to the furnace plenum or at the end
of the duct in a return filter grille(s). The use of straps and/or supports is
required to support the weight of the external filter box.
SECTION IV: GAS PIPING
GAS SAFETY
An overpressure protection device, such as a pressure regulator,
must be installed in the gas piping system upstream of the furnace
and must act to limit the downstream pressure to the gas valve so it
does not exceed 0.5 PSI (14" w.c. (3.48 kPa). Pressures exceeding
0.5 PSI (14” w.c. (3.48 kPa) at the gas valve will cause damage to
the gas valve, resulting in a fire or explosion or cause damage to
the furnace or some of its components that will result in property
damage and loss of life.
External Manual
Shutoff Valve
To Gas
Supply
Drip Leg
FIGURE 17: Upflow/Downflow Gas Piping
FIGURE 18: Horizontal Gas Piping
An accessible manual shutoff valve must be installed upstream of
the furnace gas controls and within 6 feet (1.8 m) of the furnace.
Grounded Joint Union
may be Installed
Inside or Outside Unit.
Manual
Shut-off
Valve
Gas
Pipe
Gas
Pipe
Drip
Leg
To Gas
Supply
Drip
Leg
Gas Burners
Gas Valve
Manual
Shut-off Valve
On/Off
Knob
Inlet
Pressure
Tap
FIGURE 16: Gas Valve
Plan your gas supply before determining the correct gas pipe entry.
Use 90-degree service elbow(s), or short nipples and conventional
90-degree elbow(s) to enter through the cabinet access holes.
Main
Regulator
Adjustment
Outlet
Pressure
Tap
GAS PIPING INSTALLATION
Properly sized wrought iron, approved flexible or steel pipe must be
used when making gas connections to the unit. If local codes allow the
use of a flexible gas appliance connection, always use a new listed connector. Do not use a connector that has previously serviced another gas
appliance.
Some utility companies or local codes require pipe sizes larger than the
minimum sizes listed in these instructions and in the codes. The furnace
rating plate and the instructions in this section specify the type of gas
approved for this furnace - only use those approved gases. The installation of a drip leg and ground union is required. Refer to Figure 17,
"Upflow/Downflow Gas Piping".
The furnace must be isolated from the gas supply piping system by
closing its individual external manual shutoff valve during any pressure
testing of the gas supply piping system at pressures equal to or less
than 1/2 psig (3.5 kPa).
The gas valve body is a very thin casting that cannot take any
external pressure. Never apply a pipe wrench to the body of the gas
valve when installing piping. A wrench must be placed on the octagon hub located on the gas inlet side of the valve. Placing a wrench
to the body of the gas valve will damage the valve causing improper
operation and/or the valve to leak.
Gas piping may be connected from either side of the furnace using any
of the gas pipe entry on both sides of the furnace. Refer to Figure 14,
"Dimensions".
GAS CONVERSION FOR PROPANE (LP)
This furnace is constructed at the factory for natural gas-fired operation,
but may be converted to operate on propane (LP) gas by using a factory-supplied LP conversion kit which includes a LP gas valve. Follow
the instructions supplied with the LP kit.
LoNOx furnaces requiring propane (LP) gas must have the LoNOx
screens removed prior to installation and operation. See propane
instructions.
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