Johnson Controls TM9VMP User Manual

EFFICIENCY
RATING
CERTIFIED

ISO 9001

Certified Quality

Management System

RESIDENTIAL GAS FURNACE MODELS

INSTALLATION MANUAL

TM9V*MP

(96% AFUE Two Stage Variable Speed Multi-position)

LIST OF SECTIONS

SAFETY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

DUCTWORK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

FILTERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

GAS PIPING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

ELECTRICAL POWER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

CONDENSATE PIPING AND FURNACE

VENTING CONFIGURATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

LIST OF FIGURES

Duct Attachment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Vertical Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Coil Flange . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Horizontal Right Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Horizontal Left Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

PC Series Upflow Coil Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Horizontal Left or Right application (Right Shown) . . . . . . . . . . . . . . 6

Combustible Floor Base Accessory . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Horizontal Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Typical Attic Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Typical Suspended Furnace / Crawl Space Installation . . . . . . . . . . . 7

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Side Return Cutout Markings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Gas Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Upflow/Downflow Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Horizontal Gas Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Electrical Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Thermostat Chart - Single Stage Air Conditioners

with Two Stage Variable Speed Furnaces . . . . . . . . . . . . . . . . . . . . 12

Thermostat Chart - Single Stage Heat Pump with Two Stage

Variable Speed Furnace (Hot Heat Pump or Conventional) . . . . . . 13

Thermostat Chart - Two Stage AC with

Two Stage Variable Speed Furnace . . . . . . . . . . . . . . . . . . . . . . . . 14

COMBUSTION AIR and VENT SYSTEM . . . . . . . . . . . . . . . . . . . .22

START-UP AND ADJUSTMENTS . . . . . . . . . . . . . . . . . . . . . . . . . .29

SAFETY CONTROLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

REPLACEMENT PARTS LIST . . . . . . . . . . . . . . . . . . . . . . . . . . . .36

REPLACEMENT PART CONTACT INFORMATION . . . . . . . . . . . . 36

WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

Thermostat Chart - Two Stage HP with Two Stage

Variable Speed Furnace (Hot Heat Pump or Conventional) . . . . . . .15

Typical. Condensate drain, vertical installation. . . . . . . . . . . . . . . . .16

Typical. Combustion Pipe Drain Tee. . . . . . . . . . . . . . . . . . . . . . . . .17

Upflow Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18

Downflow Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19

Horizontal Left Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20

Horizontal Right Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21

Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22

Home Layout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24

Termination Configuration - 1 Pipe . . . . . . . . . . . . . . . . . . . . . . . . . .25

Termination Configuration - 2 Pipe . . . . . . . . . . . . . . . . . . . . . . . . . .25

Termination Configuration - 2 Pipe Basement . . . . . . . . . . . . . . . . .25

Double Horizontal Combustion Air Intake and Vent Termination . . .25

Double Vertical Combustion Air Intake and Vent Termination . . . . . 25

Direct Vent Air Intake Connection and Vent Connection . . . . . . . . .26

Combustion Airflow Path Through The Furnace Casing . . . . . . . . .26

Outside and Ambient Combustion Air . . . . . . . . . . . . . . . . . . . . . . . .27

Attic and Crawl Space Combustion Air Termination . . . . . . . . . . . . .28

Gas Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

Reading Gas Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

Furnace Control Board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32

Furnace Control Event Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . .35

Wiring Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

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

Nominal Manifold Pressure - High Fire . . . . . . . . . . . . . . . . . . . . . . 10

Nominal Manifold Pressure - Low Fire . . . . . . . . . . . . . . . . . . . . . . . 10

Ratings & Physical / Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . 11

Maximum Equivalent Pipe Length . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Elbow Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

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 IV listed and may not be common vented with
another gas appliance as allowed by the National Fuel Gas Code.

Equivalent Length of Fittings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Combustion Air Intake and Vent Connection Size at

Furnace (All Models) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23

Estimated Free Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26

Unconfined Space Minimum Area in Square Inch . . . . . . . . . . . . . . 27

Free Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27

Gas Rate (CU FT/HR) at Full Input . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Inlet Gas Pressure Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

Nominal Manifold Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

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 minor or moderate injury.
alert against unsafe practices and hazards involving only property dam­age.

.

.

It is also used to

438335-UIM-B-0509

438335-UIM-B-0509

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 qualified contractor, installer or service agency should

install this product.

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, "COMBUSTION AIR and VENT SYSTEM" 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 Figures 12. 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-Hz 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.

• Buildings with indoor pools

• Chemical exposure

• Commercial buildings

• Furnaces installed in hobby or craft rooms

• Furnaces installed in laundry rooms

• Furnaces installed near chemical storage areas

• Restricted Environments

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.

• Antistatic fabric softeners for clothes dryers

• Carbon tetrachloride

• Cements and glues

• Chlorinated waxes and cleaners

• Chlorine-based swimming pool chemicals

• Cleaning solvents (such as perchloroethylene)

• De-icing salts or chemicals

• Halogen type refrigerants

• Hydrochloric acid

• Masonry acid washing materials

• Permanent wave solutions

• Printing inks, paint removers, varnishes, etc.

• Water softening chemicals

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

438335-UIM-B-0509

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.

Johnson Controls Unitary Products 3

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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 (particularly
when the appliance is not using outdoor combustion air).

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 to provide
proper condensate drainage.

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. Ambient temperatures must not fall below 32°F
(0°C) unless the condensate system is protected from freezing.

Improper installation in an ambient below 32ºF (0.0° C) could create
a hazard, resulting in damage, injury or death.

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.

3. If this furnace is installed in an unconditioned space and an
extended power failure occurs, there will be potential damage to
the internal components. Following a power failure situation, do
not operate the unit until inspection and repairs are performed.

4. Special precautions MUST be made if installing furnace in an area
which may drop below freezing. This can cause improper opera­tion or damage to the equipment. If the furnace is installed in an
area that has the potential of freezing, the drain line must be pro­tected. Use a 3 to 6 watt per foot at 115 vac, 40º F (4.4°C) self-reg­ulating, shielded and waterproof heat tape. Wrap the drain line
outside of the furnace with the heat tape and secure with ties. Fol­low the heat tape manufacturer's recommendations.

Liquid anti-freeze will cause damage to internal plastic parts of this
furnace. DO NOT attempt to winterize the furnace using liqu id

anti-freeze.

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” (46 cm) above the floor, and the furnace must be located or
protected to avoid physical damage by vehicles.

Table 1:

Unit Clearances to Combustibles

Application

Top 1" 0" 0"
Vent 0" 0" 0"
Rear 0" 0" 0"
Side 0" 0" 1"

Front* 0" 0" 0"

Floor Combustible

Closet Yes Yes Yes

Line Contact No No Yes

1. For combustible floors only when used with special sub-base.
* 24" clearance in front and 18" on side recommended for service access.
All furnaces approved for alcove and attic installation.

Upflow Downflow Horizontal

1

Combustible

Combustible

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.

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” (10.2 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” (5.1 cm) minimum spacing may be needed to ensure
against drain pan distortion.

4 Johnson Controls Unitary Products

438335-UIM-B-0509

Factory
installed

For duct attachment,
if needed.

UPFLOW

DOWNFLOW

Furnace

Furnace

ALTERNATE
FLANGE LOCATION
(Used for downflow or
horizontal left installations)

FACTORY

FLANGE

LOCATION

(Used for upflow

or horizontal

right installations)

On all installations without a coil, a removable access panel is recom­mended 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.

The duct system must be properly sized to obtain the correct airflow
for the furnace size that is being installed.

Refer to T able7 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.

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 must remain in the rotated down posi­tion as shipped.

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

On all installations without a coil, a removable access panel is rec­ommended 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.

COIL/FURNACE ASSEMBLY - MC/FC/PC SERIES
COILS

FIGURE 1: Duct Attachment

DUCTWORK INSTALLATION AND SUPPLY PLENUM
CONNECTION - UPFLOW/HORIZONTAL

FLOOR BASE AND DUCTWORK INSTALLATION ­DOWNFLOW

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.

Johnson Controls Unitary Products 5

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.

Installations on combustible material or directly on any
floors must use a combustible floor base shown in Figures

8. 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

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
Figures 2 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 Figures 3.

FIGURE 3: Coil Flange

438335-UIM-B-0509

Furnace

Mounting Plate

Furnace

Mounting Plate

Flexible
Duct Collar

Do not drill
or Screw
this flange

Field
Fabricated
Ductwork

Upflow
Coil

Upflow
Furnace

Secondary

Drain

Primary

Drain

D

C

(Min)

Alternate

Drain Location

Use tie plate
supplied with coil

Air flow

Gas Furnace

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.

FIGURE 4: Horizontal Right Application
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.

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
Figures 6.

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
Figures 6

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 Figures 6

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 6.

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 Figure 6.

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 Figure 6.

6 Johnson Controls Unitary Products

FIGURE 7: Horizontal Left or Right application (Right Shown)

438335-UIM-B-0509

FURNACE

WARM AIR PLENUM
WITH 1” FLANGES

FIBERGLASS
INSULATION

FIBERGLASS TAPE
UNDER FLANGE

COMBUSTIBLE FLOOR
BASE ACCESSORY

Return
Air

Sediment

Trap

Gas Piping

Supply
Air

Vent (Maintain
required
clearances to
combustibles)

Line contact only permissible
between lines formed by the
intersection of furnace top
and two sides and building
joists, studs or framing

12”

30” MIN.
Work Area

Filter rack
must be a minimum
distance
of 18” (45.7 cm)
from the
furnace

12”

Sheet metal in
front of furnace
combustion air
Openings is
Recommended

Support
Rod

Support
Angle (x3)

Maintain 6” minimum
clearance between support
rods and front of furnace

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.

ATTIC INSTALLATION

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 Figures 10.

When a furnace is installed in an attic or other insulated space,
keep all insulating materials at least 12” (30.5 cm) away from fur­nace and burner combustion air openings.

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.

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.

Johnson Controls Unitary Products 7

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.

FIGURE 11: Typical Suspended Furnace / Crawl Space Installation

438335-UIM-B-0509

FRONT

33

A

LEFT SIDE

Combustion Air Inlet

Condensate Drain
(Downflow)

Vent Outlet

Thermostat
Wiring

28.5”

Gas Pipe
Entry

Electrical
Entry

Condensate
Drain

Thermostat
Wiring

RIGHT SIDE

Vent Outlet

Condensate Drain
(Downflow)

14”

1”

1.5”

23”

Combustion Air Inlet

Gas Pipe
Entry

Electrical
Entry

Condensate
Drain

Optional Return Air
Cutout (Either side)

29.5”

(For Cladded door add appoximately an additional .75”)

C

SUPPLY END

.56”

.56”

20”

B

3”

23.8”

.56”

Combustion
Air Inlet

Vent
Outlet

RETURN END

B

24.25”

Front of
Furnace

Corner
Markings

Side of
Furnace

FIGURE 12: Dimensions

Table 3: Cabinet and Duct Dimensions

BTUH (kW)

Input

Nominal

CFM (m

3

/min)

Cabinet

Size

Cabinet Dimensions (Inches)

A (in) A (cm) B (in) B (cm) C (in) C (cm) Lbs (kg)

Approximate

Operating Weights

60 (17.6) 1200 (34.0) B 17 1/2 44.4 16 3/8 41.6 13 1/4 33.7 122 (55.3)
80 (23.4) 1200 (34.0) B 17 1/2 44.4 16 3/8 41.6 14 3/4 37.5 126 (57.1)

80 (23.4) 1600 (45.3) C 21 53.3 19 7/8 50.5 16 1/2 41.9 136 (61.7)
100 (29.3) 1600 (45.3) C 21 53.3 19 7/8 50.5 18 1/4 46.4 142 (64.4)
100 (29.3) 2000 (56.6) C 21 53.3 19 7/8 50.5 18 1/4 46.4 145 (65.8)
120 (35.1) 2000 (56.6) D 24 1/2 62.2 23 3/8 59.4 21 3/4 55.2 156 (70.7)

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.
NOTE: Single side return above 1800 CFM is approved as long as the

filter velocity does not exceed filter manufacturer’s recommendation
and a transition is used to allow use on a 20x25 filter.

Table 4: Recommended Filter Sizes (High Velocity 600 FPM)

NOTES:

CFM

(m³/min)

Cabinet

Size

Side

(in)

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
2000 (56.6) D (2) 16 x 25 22 x 25

1.Air velocity through throwaway type filters may not exceed 300 feet per

2.Do not exceed 1800 CFM using a single side return and a 16x25 filter. For

minute (91.4 m/min). All velocities over this require the use of high velocity
filters.

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.

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 Figures 13.

FIGURE 13: 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 Figures 12.

8 Johnson Controls Unitary Products

HORIZONTAL APPLICATION

INLET

WRENCH
BOSS

INLET
PRESSURE
PORT

ON OFF
SWITCH

LOW STAGE REGULATOR
ADJUSTMENT

OUTLET

OUTLET
PRESSURE
PORT

VENT
PORT

HIGH STAGE REGULATOR
ADJUSTMENT

External Manual
Shutoff Valve

To Gas
Supply

To Gas

Supply

Grounded Joint Union

may be Installed

Inside or Outside Unit.

Drip Leg

Manual
Shut-off
Valve

Gas
Pipe

Gas
Pipe

Drip
Leg

Manual
Shut-off Valve

Gas Valve

Gas Burners

Drip
Leg

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 filter
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

438335-UIM-B-0509

FIGURE 15: Upflow/Downflow Gas Piping

An overpressure protection device, such as a pressure regulator,

FIGURE 16: Horizontal Gas Piping

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 psig [14" w.c. (3.48 kPa)]. Pressures exceed­ing 0.5 psig [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

An accessible manual shutoff valve must be installed upstream of

the furnace gas controls and within 6 feet (1.8 m) of the furnace.
the furnace or some of its components that will result in property
damage and loss of life.

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 0.5 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 octa-

gon 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 knockouts on both sides of the furnace. Refer to

FIGURE 14: Gas Valve

Figures 12.

GAS ORIFICE CONVERSION FOR PROPANE (LP)

This furnace is constructed at the factory for natural gas-fired operation,

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.

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 Figures 15.

Johnson Controls Unitary Products 9

but may be converted to operate on propane (LP) gas by using a
factory-supplied LP conversion kit. Follow the instructions supplied with
the LP kit.

HIGH ALTITUDE GAS ORIFICE CONVERSION

This furnace is constructed at the factory for natural gas-fired operation
at 0 –5,000 feet (0 – 1,524 m) above sea level.

The manifold pressure must be changed in order to maintain proper
and safe operation when the furnace is installed in a location where the
altitude is greater than 5,000 feet (1,524 m) above sea level. Refer to
Table 5 for proper manifold pressure settings.

HIGH ALTITUDE PRESSURE SWITCH CONVERSION

For installation where the altitude is less than 5,000 feet (1,524m), it is
not required that the pressure switch be changed unless you are in an
area subject to low pressure inversions.

438335-UIM-B-0509

Table 5: Nominal Manifold Pressure - High Fire

Manifold Pressures (in. w.c.) Manifold Pressures (kPa)

Altitude (feet) Altitude (m)

0-7999 8000-8999 9000-9999 0-2437 2438-2742 2743-3048
800 3.5 3.5 3.5
850 3.5 3.5 3.5 31.7 0.87 0.87 0.87
900 3.5 3.5 3.5 33.5 0.87 0.87 0.87
950 3.5 3.5 3.3 35.4 0.87 0.87 0.81

1000 3.5 3.2 2.9 37.3 0.87 0.80 0.73

(BTU/cu ft.)

Gas Heating Value

1050 3.5 2.9 2.7 39.1 0.87 0.73 0.67
1100 3.2 2.7 2.4 41.0 0.80 0.66 0.61

2500 (LP) 9.8 8.2 7.5 93.2 (LP) 2.44 2.03 1.86

29.8 0.87 0.87 0.87

(MJ/cu m)

Gas Heating Value

TABLE 6:

Nominal Manifold Pressure - Low Fire

First Stage Manifold Pressures (in. w.c.) First Stage Manifold Pressures (kPa)

Altitude (feet) Altitude (m)

0-7999 8000-8999 9000-9999 0-2437 2438-2742 2743-3048
800 1.7 1.7 1.7
850 1.7 1.7 1.7 31.7 0.42 0.42 0.42
900 1.7 1.7 1.7 33.5 0.42 0.42 0.42
950 1.7 1.7 1.5 35.4 0.42 0.42 0.38

1000 1.6 1.5 1.4 37.3 0.41 0.37 0.34

(BTU/cu ft.)

Gas Heating Value

1050 1.5 1.4 1.3 39.1 0.37 0.34 0.31
1100 1.3 1.2 1.1 41.0 0.34 0.31 0.28

2500 (LP) 4.1 3.8 3.5 93.2 (LP) 1.03 0.95 0.87

(MJ/cu m)

Gas Heating Value

29.8 0.42 0.42 0.42

PROPANE AND HIGH ALTITUDE CONVERSION KITS

It is very important to choose the correct kit and/or gas orifices for the altitude and the type of gas for which the furnace is being installed.
Only use natural gas in furnaces designed for natural gas. Only use propane (LP) gas for furnaces that have been properly converted to use pro-

pane (LP) gas. Do not use this furnace with butane gas.
Incorrect gas orifices or a furnace that has been improperly converted will create an extremely dangerous condition resulting in premature heat

exchanger failure, excessive sooting, high levels of carbon monoxide, personal injury, property damage, a fire hazard and/or death.
High altitude and propane (LP) conversions are required in order for the appliance to satisfactory meet the application.
An authorized distributor or dealer must make all gas conversions.
In Canada, a certified conversion station or other qualified agency, using factory specified and/or approved parts, must perform the conversion.
The installer must take every precaution to insure that the furnace has been converted to the proper gas orifice size when the furnace is installed.
Do not attempt to drill out any orifices to obtain the proper orifice size. Drilling out a gas orifice will cause misalignment of the burner flames,
causing premature heat exchanger burnout, high levels of carbon monoxide, excessive sooting, a fire hazard, personal injury, property damage
and/or death.

SECTION V: ELECTRICAL POWER

ELECTRICAL POWER CONNECTIONS

Field wiring to the unit must be grounded. Electric wires that are field
installed shall conform to the temperature limitation for 63°F (35°C) rise
wire when installed in accordance with instructions. Refer to T able7 in
these instructions for specific furnace electrical data.

Use copper conductors only.

10 Johnson Controls Unitary Products

438335-UIM-B-0509

Electrical Entry

Junction
Box

L1-Hot

Neutral

Connect ground
lead to screw

BLK

WHT

Table 7: Ratings & Physical / Electrical Data

Input

High/Low

MBH kW MBH kW CFM
60/39 18/11 58/3 7 17/11 1200 34 17-1/2 44.4 9 96 35 - 65 1.6 - 18.3 35 - 65 1.6 - 18.3
80/52 23/15 77/5 0 22/14 1200 34 17-1/2 44.4 9 96 35 - 65 1.6 - 18.3 30 - 60 -1 - 15.5
80/52 23/15 77/5 0 22/14 1600 45.3 21 53.3 12 96 35 - 65 1.6 - 18.3 35 - 65 1.6 - 18.3

100/65 29/19 96/62 28/18 1600 45.3 21 53.3 12 96 35 - 65 1.6 - 18.3 30 - 60 -1 - 15.5
100/65 29/19 96/62 28/18 2000 56.6 21 53.3 14 96 35 - 65 1.6 - 18.3 35 - 65 1.6 - 18.3
120/78 35/23 115/75 33/22 2000 56.6 24-1/2 62.2 14 96 35 - 65 1.6 - 18.3 35 - 65 1.6 - 18.3

Input

High/Low

MBH kW °F °C HP Amps in. cm Lbs. Kg.
60/39 18/11 170 76.7 1/2 7 11 x 8 27.9 x 20.3 15 14 122 55.3
80/52 23/15 175 79.4 1/2 7 11 x 8 27.9 x 20.3 15 14 126 57.1
80/52 23/15 175 79.4 3/4 10.2 11 x 10 27.9 x 25.4 15 14 136 61.7

100/65 23/15 175 79.4 3/4 10.2 11 x 10 27.9 x 25.4 15 14 142 64.4
100/65 29/19 175 79.4 1 12.7 11 x 11 27.9 x 27.9 20 12 145 65.7
120/78 35/23 170 76.7 1 12.7 11 x 11 27.9 x 27.9 20 12 156 70.7

Annual Fuel Utilization Efficiency (AFUE) numbers are determined in accordance with DOE test procedures.
Wire size and over current protection must comply with the National Electrical Code (NFPA-70-latest edition) and all local codes.
The furnace shall be installed so that the electrical components are protected from water.

Output

High/Low

Max. Outlet

Air Temp.

Nominal

Airflow

m3/min

Blower Blower Size

Cabinet Width

in. cm % °F °C °F °C

Over-current

Total Unit

Amps

Max.

Protect

AFUE

Min. Wire Size
(awg) @ 75 ft.

One Way

High Fire

Air Temp. Rise

Operating

Weight

Low Fire

Air Temp. Rise

SUPPLY VOLTAGE CONNECTIONS

FIGURE 17: Electrical Wiring

1. Provide a power supply separate from all other circuits. Install

2. Remove the wiring box cover screws. Route all power wiring

3. The furnace's control system requires correct polarity of the power

Johnson Controls Unitary Products 11

overcurrent protection and disconnect switch per local/national
electrical codes. The switch should be close to the unit for conve­nience in servicing. With the disconnect or fused switch in the OFF
position, check all wiring against the unit wiring label. Refer to the
wiring diagram in this instruction.

through a conduit connector or other proper bushing that has been
installed into the unit opening and the junction box. In the junction
box there is a black wire, a white wire and a green ground screw.
Connect the power supply as shown on the unit’s wiring label
located on the inside of the blower compartment door, or the wiring
schematic in this section. Connect the black wire to L1 (hot) from
the power supply. Connect the white wire to neutral. Connect the
ground wire (installer-supplied) to the green (equipment ground)
screw. An alternate wiring method is to use a field-provided 2”
(5.1 cm) x 4” (10.2 cm) box and cover on the outside of the fur­nace. Route the furnace leads into the box using a protective
bushing where the wires pass through the furnace panel. After
making the wiring connections replace the wiring box cover and
screws. Refer to Figures 17.

supply and a proper ground connection. Refer to Figures 17.

The power connection leads and wiring box may be relocated to the
left side of the furnace. Remove the screws and cut wire tie holding
excess wiring. Reposition on the left side of the furnace and fasten
using holes provided.

LOW VOLTAGE CONTROL WIRING CONNECTIONS

Install the field-supplied thermostat by following the instructions that
come with the thermostat. With the thermostat set in the OFF position
and the main electrical source disconnected, connect the thermostat
wiring from the wiring connections on the thermostat to the terminal
board on the ignition module, as shown in Figures 18. Electronic ther­mostats may require the common wire to be connected. Apply strain
relief to thermostat wires passing through cabinet. If air conditioning
equipment is installed, use thermostat wiring to connect the Y and C
terminals on the furnace control board to the proper wir es on the con­densing unit (unit outside).

Set the heat anticipator in the room thermostat to 0.4 amps. Setting
it lower will cause short cycles. Setting it higher will cause the room
temperature to exceed the set points.

Some electronic thermostats do not have adjustable heat anticipa­tors. They should be set to six cycles per hour. Follow the thermo­stat manufacturer's instructions.

The 24-volt, 40 VA transformer is sized for the furnace components
only, and should not be connected to power auxiliary devices such as
humidifiers, air cleaners, etc. The transformer may provide power for an
air conditioning unit contactor.

438335-UIM-B-0509

AC 9A Single Stage Air Conditioner – Two Stage Variable Speed Furnace

Connection of the “C”

terminal, 24-Volt common

is optional when used with

batteries

C

24 – Volt Common

R

24 – Volt Hot

Y

First Stage Compressor

Y2

Second Stage

Compressor

G

Fan

*DN22C00124

THERMOSTAT

W2

Second Stage Heat

C

24 – Volt Common

R

24 – Volt Hot

Y1

First Stage Compressor

Y2

Second Stage

Compressor

G

Fan

*DP22U70124

THERMOSTAT

W2

Second Stage Heat

Step 1 of Thermostat User

Configuration Menu must

be set to MS 2

W

First Stage Heat

E/W1

First Stage Heat

Connection of the “C”

terminal, 24-Volt common

is optional when used with

batteries

Part Number:

S1-2HU16700124

External Humidistat

(Optional)

Open on Humidity Rise

C

24 – Volt Common

Y

Compressor

Y

Compressor Contactor

SINGLE STAGE

AIR

CONDITIONER

Part Numbers:

SAP = Legacy
265904 = 031-09169
449572

1

C

24 – Volt Common

R

24 – Volt Hot

Y1
Single Stage
Compressor

TWO STAGE

VARIABLE SPEED

FURNACE CONTROL

G

Fan

TWO STAGE

VARIABLE SPEED

FURNACE

W/W1

First Stage Heat

Y/Y2

Second or Full

Stage Compressor

W2

Second Stage Heat

O

Reversing Valve

X/L

Malfunction Light

DHUM

Dehumidification

1

Move DHUM

jumper to “YES”

if humidistat is to be used.

PV(8/9)

ID MODELS

(F/L)*(8/9)V
(G/L)*(8/9)V

C

24 – Volt Common

Y

First Stage Compressor

Y2

Second Stage

Compressor

G

Fan

*PP32U70124

THERMOSTAT

W2

Second Stage Heat

R
24 – Volt Hot
(Heat XFMR)

RC
24 – Volt Hot
(Cool XFMR)

Connection of the “C”

terminal, 24-Volt common

is optional when used with

batteries

Thermostat Installer Setup

0170-System Type-must

be set to 9-2 Heat/1 Cool

Multistage Conventional

C

24 – Volt Common

Y

First Stage Compressor

Y2

Second Stage

Compressor

G

Fan

*DN22U00124

THERMOSTAT

W2

Second Stage Heat

R
24 – Volt Hot
(Heat XFMR)

RC
24 – Volt Hot
(Cool XFMR)

W

First Stage Heat

W

First Stage Heat

Connection of the “C”

terminal, 24-volt common

is optional when used with

batteries

Thermostat Installer Setup

1-System Type-must

be set to 7-2 Heat/1 Cool

Multistage Conventional

Thermostat Installer Setup
15-Compressor Protection

-must be set to 5
2

2

TM(8/9)V

For additional connection diagrams for all UPG equipment refer to “Low Voltage System Wiring” document available on-line at www.upgnet.com in
the Product Catalog Section.

FIGURE 18: Thermostat Chart - Single Stage Air Conditioners with Two Stage Variable Speed Furnaces

12 Johnson Controls Unitary Products

Part Numbers:

SAP = Legacy
265904 = 031-09169
449572

2

C

24 – Volt Common

R

24 – Volt Hot

Y1
Single Stage
Compressor

TWO STAGE

VARIABLE SPEED

FURNACE CONTROL

G

Fan

TWO STAGE

VARIABLE SPEED

FURNACE

W/W1

First Stage Heat

Y/Y2

Second or Full

Stage Compressor

W2

Second Stage Heat

O

Reversing Valve

X/L

Malfunction Light

DHUM

Dehumidification

2

Move HEAT PUMP

jumper to “YES”

Move DHUM

jumper to “YES”

if humidistat is to be used.

PV(8/9)

ID MODELS

(F/L)*(8/9)V
(G/L)*(8/9)V

C

24 – Volt Common

R

24 – Volt Hot

Y1

First Stage Compressor

O

Reversing Valve

Energized in Cool

L

Malfunction Light

G

Fan

*DP32H70124

THERMOSTAT

W1

Second Stage

Aux. Heat

E

Emergency Heat

W2

Third Stage Heat

Step 1 of Thermostat

Installer / Configuration

Menu must be set to

Heat Pump 1

C

24 – Volt Common

R

24 – Volt Hot

Y1

First Stage Compressor

O

Reversing Valve

Energized in Cool

L

Malfunction Light

Y2

Second Stage

Compressor

G

Fan

*BP21H50124
*BN21H00124
*DP21H40124
*DN21H00124

THERMOSTAT

E

Emergency Heat

W2

Second Stage Heat

B/O Switch on Thermostat

must be in the O position

24VAC Humidifier

(Optional)

External Humidistat

(Optional)

Open on Humidity Rise

Part Number:

S1-2HU16700124

O

Reversing Valve

Energized in Cool

C

24 – Volt Common

R

24 – Volt Hot

W1 OUT

First Stage Heat

W2 OUT

Second Stage Heat

Y2 OUT

Second Stage

Compressor

Y1
Single Stage
Compressor

X/L

Malfunction Light

Y2

Second Stage

Compressor

W

Auxiliary Heat

BS

Bonnet Sensor

BSG

Bonnet Sensor

YORKGUARD VI

CONTROL

SINGLE STAGE

HEAT PUMP

Change FFuel jumper

on the heat pump control

to “ON”

1

H*3

YMB

YZB

OD MODELS

Part Numbers:

SAP = Legacy

126768 = 031-09137
18395 = 031-01996
340512 = 031-09178

1

Y2

Second Stage

Compressor

HP 15A Single Stage Heat Pump – Two Stage Variable Speed Furnace (Hot Heat Pump or Conventional)

Change Hot Heat Pump

jumper on the heat pump

control to “ON” if Hot Heat

Pump Operation is desired.

C

24 – Volt Common

Y

First Stage Compressor

O/B

Reversing Valve

L

Malfunction Light

G

Fan

*DN22U00124

THERMOSTAT

E

Emergency Heat

AUX

Auxiliary Heat

R
24 – Volt Hot
(Heat XFMR)

RC
24 – Volt Hot
(Cool XFMR)

Thermostat Installer Setup
1-System Type-must be set
to 5 – 2 Heat/1 Heat Pump

Thermostat Installer Setup

2-Changeover Valve-must

be set to 0 – O/B terminal

Energized in Cooling

External Humidistat

(Optional)

Open on Humidity Rise

3

3

3

Bonnet Sensor Kit

(Optional)

S1-37309243000

TM(8/9)V

438335-UIM-B-0509

FIGURE 19: Thermostat Chart - Single Stage Heat Pump with Two Stage Variable Speed Furnace (Hot Heat Pump or Conventional)

Johnson Controls Unitary Products 13

438335-UIM-B-0509

AC 24C Two Stage Air Conditioner – Two Stage Variable Speed Furnace

TWO STAGE

AIR

CONDITIONER

C

24 – Volt Common

R

24 – Volt Hot

Y1

First Stage Compressor

Y2

Second Stage

Compressor

C

24 – Volt Common

Y1

First Stage Compressor

L

Malfunction Light

Y2

Second Stage

Compressor

G

Fan

*PP32U71124
*PP32U72124

THERMOSTAT

R

24 – Volt Hot

W2

Second Stage Heat

DHM

Dehumidification

HM

Humidistat

Step 1 of Thermostat User

Configuration Menu must

be set to MLTISTG

E/W1

First Stage Heat

24VAC Humidifer

(Optional)

Optional Harness

Part Numbers:

SAP = Legacy
265904 = 031-09169
449572

1

C

24 – Volt Common

R

24 – Volt Hot

Y1

Single Stage

Compressor

TWO STAGE

VARIABLE SPEED

FURNACE CONTROL

G

Fan

TWO STAGE

VARIABLE SPEED

FURNACE

W/W1

First Stage Heat

Y/Y2

Second or Full

Stage Compressor

W2

Second Stage Heat

O

Reversing Valve

X/L

Malfunction Light

DHUM

Dehumidification

1

Move DHUM

jumper to “YES”

if humidistat is to be used.

(G/L)*(8/9)V

(F/L)*(8/9)V

PV(8/9)

ID MODELS

Comfort Alert Interface

(two pin connector)

E2/P Switch must be in the

E2 position

TM(8/9)V

FIGURE 20: Thermostat Chart - Two Stage AC with Two Stage Variable Speed Furnace

14 Johnson Controls Unitary Products

O

Reversing Valve

Energized in Cool

C

24 – Volt Common

R

24 – Volt Hot

W1 OUT

First Stage Heat

W2 OUT

Second Stage Heat

Y2 OUT

Second Stage

Compressor

Y1
Single Stage
Compressor

X/L

Malfunction Light

Y2

Second Stage

Compressor

W

Auxiliary Heat

BS

Bonnet Sensor

BSG

Bonnet Sensor

TWO STAGE
HEAT PUMP

C

24 – Volt Common

Y1

First Stage Compressor

L

Malfunction Light

Y2

Second Stage

Compressor

G

Fan

*PP32U71124
*PP32U72124

THERMOSTAT

R

24 – Volt Hot

E/W1

First Stage Aux. Heat

W2

Second Stage

Aux. Heat

DHM

Dehumidistat

HM

Humidistat

O

Reversing Valve

Energized in Cool

Change FFuel jumper

on the heat pump control

to “ON”

Part Numbers:

SAP = Legacy

126768 = 031-09137
18395 = 031-01996
340512 = 031-09178

1

1

Part Numbers:

SAP = Legacy
265904 = 031-09169
449572

2

C

24 – Volt Common

R

24 – Volt Hot

Y1
Single Stage
Compressor

TWO STAGE

VARIABLE SPEED

FURNACE CONTROL

G

Fan

TWO STAGE

VARIABLE SPEED

FURNACE

W/W1

First Stage Heat

Y/Y2

Second or Full

Stage Compressor

W2

Second Stage Heat

O

Reversing Valve

X/L

Malfunction Light

DHUM

Dehumidification

2

Move HEAT PUMP

jumper to “YES”

Move DHUM

jumper to “YES”

if humidistat is to be used.

PV(8/9)

ID MODELS

(F/L)*(8/9)V

YORKGUARD VI

CONTROL

(G/L)*(8/9)V

YZE

OD MODELS

YZH

H*5
H*8

24VAC Humidifier

(Optional)

Step 1 of the Thermostat

Installer Table must be

set to Heat Pump

E2/P Switch must be in the

E2 position

Step 2 of the Thermostat

Installer Table must be

set to 2

HP 24A Two Stage Heat Pump – Two Stage Variable Speed Furnace (Hot Heat Pump or Conventional)

Change Hot Heat Pump

jumper on the heat pump

control to “ON” if Hot Heat

Pump Operation is desired.

Bonnet Sensor Kit

(Optional)

S1-37309243000

TM(8/9)V

438335-UIM-B-0509

FIGURE 21: Thermostat Chart - Two Stage HP with Two Stage Variable Speed Furnace (Hot Heat Pump or Conventional)

Johnson Controls Unitary Products 15

438335-UIM-B-0509

To Open Or
Vented Drain

Tee

5” Min.

Open Stand Pipe

(Anti-siphon air vent)

ACCESSORY CONNECTIONS

The furnace control will allow power-switching control of various
accessories.

ELECTRONIC AIR CLEANER CONNECTION

Two 1/4” (6.4 mm) spade terminals (EAC and NEUTRAL) for electronic
air cleaner connections are located on the control board. The terminals
provide 115 VAC (1.0 amp maximum) during circulating blower
operation.

HUMIDIFIER CONNECTION

Two 1/4” (6.4 mm) spade terminals (HUM and NEUTRAL) for humidifier
connections are located on the control board. The terminals provide
115 VAC (1.0 amp maximum) during heating system operation.

A mounting hole is provided on the control panel next to the furnace
control board for mounting a humidifier transformer if required.

TWINNING

These furnaces are not to be twinned. If more than one furnace is
needed in an application, each furnace must have its own complete
duct system and its own wall thermostat.

SECTION VI: CONDENSATE PIPING AND
FURNACE VENTING CONFIGURATION

CONDENSATE DRAIN LOCATION

As shipped from the factory:

• For all 060, & 080K input furnaces the main drain is plumbed
through the casing right-side opening when viewed from the front
of the furnace.

• For all 100 & 120K input furnaces the main drain is plumbed
through the casing left-side opening when viewed from the front
of the furnace.

NOTE: The Figures 24 - 27 show the condensate drain arrange­ment for the various possible furnace and vent blower positions.

The condensate hoses must slope downwards at all points.

If an external vent tee is being installed, then it must have its own
condensate trap before it is disposed into an open or vented drain.

This is not to be considered as a second trap as referenced
elsewhere in this document.

The furnace condensate pan is self priming and con­tains an internal trap to prevent flue gas leaking. Do
not install an external condensate trap.

When drain hose routing changes are required (shown in Figures 24-

27), be sure to cap all un-used openings.
If rerouting hoses - excess length should be cut off so that no sagging

loops will collect and hold condensate - which will cause the furnace to
not operate.

No hose clamps are needed for connecting to the condensate pan.

The furnace, evaporator coil, and humidifier drains may be com­bined and drained together. The evaporator coil drain must have
an external, field-supplied trap prior to the furnace drain connec­tion. All drain connections (furnace, evaporator coil, or humidifier)
must be terminated into an open or vented drain as close to the
respective equipment as possible.

Condensate must be disposed of properly. Follow local plumbing
or wastewater codes. The drain line must maintain a 1/4" per foot
(21 mm/m) downward slope to the drain.

FIGURE 22: Typical. Condensate drain, vertical installation.
The condensate will flow to the drain better if an open stand pipe is

installed in the drain line. See Figure 23.
If evaporator coil or humidifier drains are combined with the furnace

drain, then the open stand pipe could be raised higher, above the 5”
minimum.

It is possible for condensation to form inside the combustion air
(intake) pipe in the summer months if significant length of combus­tion air pipe passes through conditioned space. This problem can
be averted by the addition of a simple drain tee, or a drain tee with a
drain on the combustion air pipe as close to the furnace as possi­ble, as shown in Figure 24. This is true for all long horizontal vent­ing in any furnace configuration. This will prevent the condensate
from entering the furnace.

16 Johnson Controls Unitary Products

FIGURE 23: Typical. Combustion Pipe Drain Tee.

Connect to Drain

Trap

Combustion Air Pipe

Tee with Drain Trap

Exhaust Pipe

438335-UIM-B-0509

CONDENSATE DRAIN TERMINATION

A condensate sump pump MUST be used if required by local codes, or
if no indoor floor drain is available. The condensate sump pump must
be approved for use with acidic condensate.

DO NOT terminate condensate drain in a chimney, or where the
drain line may freeze. The line must terminate at an inside drain to
prevent freezing of the condensate and possible property damage.

DO NOT trap the drain line at any other location than at the conden­sate drain trap supplied with the furnace.

CONDENSATE DRAIN TRAP AND DRAIN FREEZE
PROTECTION

Special precautions MUST be made if installing furnace in an area
which may drop below freezing. This can cause improper operation or
damage to the equipment. If the furnace is installed in an area that has
the potential of freezing, the drain line must be protected. Use a 3 to 6
Watt per foot at 115 vac, 40ºF (4.4°C) self-regulating, shielded and
waterproof heat tape. Wrap the drain line outside of the furnace with the
heat tape and secure with ties. Follow the heat tape manufacturer's rec­ommendations.

Liquid anti-freeze will cause damage to internal plastic parts of this
furnace. DO NOT attempt to winterize the furnace using liquid

anti-freeze.

Johnson Controls Unitary Products 17

438335-UIM-B-0509

INDUCER ROTATED FOR

LEFT SIDE VENTING

UPFLOW

AS RECEIVED

INDUCER ROTATED FOR

RIGHT SIDE VENTING

When drain hose routing changes are required, be sure to cap all un-used openings.

If rerouting hoses - excess length should be cut off so that no sagging loops will collect

and hold condensate, which will cause the furnace to not operate.

Shorten pressure

switch hose.

Re-route and shorten

pressure switch hose.

Shorten rain

gutter hose.

Move rain gutter

hose to this position.

For 100, 120K input furnaces, the condensate drain is

plumbed toward the left casing outlet from the factory.

For 060 & 080K input furnaces, the condensate drain

is plumbed toward the right casing outlet from the factory.

Condensate drain may exit

cabinet on either side.

1

2

1

2

FIGURE 24: Upflow Configuration

18 Johnson Controls Unitary Products

AIRFLOW

AIRFLOW

Move rain

gutter hose

to this position.

DOWNFLOW - INDUCER ROTATED

FOR LEFT SIDE VENTING

DOWNFLOW - INDUCER ROTATED

FOR RIGHT SIDE VENTING

Move pressure switch

hose to this position.

NOTE: May require

the longer hose that

is provided with

wider cabinets.

Move condensate

drain hose to this

position (may exit

either side of the

cabinet).

Move rain gutter

hose to this position.

When drain hose routing changes are required, be sure to cap all un-used openings.

If rerouting hoses - excess length should be cut off so that no sagging loops will collect

and hold condensate, which will cause the furnace to not operate.

1

2

4

3

438335-UIM-B-0509

FIGURE 25: Downflow Configuration

Johnson Controls Unitary Products 19

438335-UIM-B-0509

HORIZONTAL - LEFT

INDUCER ROTATED

HORIZONTAL - LEFT

INDUCER AS RECEIVED

AIRFLOW

AIRFLOW

Move pressure switch hose

to this position.

NOTE: May require the longer

hose that is provided with

wider cabinets.

Move rain gutter hose to this position

NOTE: May require hose extension

that is provided with wider cabinets.

Move rain gutter

hose to this position.

Move pressure switch

hose to this position.

NOTE: May require the longer

hose that is provided with

wider cabinets.

Change condensate drain

connection to the 90° fitting

provided.

Move condensate

drain hose to this

position.

Move rain gutter hose to this

position NOTE: May require hose

extension that is provided with

wider cabinets.

Move condensate

drain hose to this position.

Change condensate

drain connection to

the 90° fitting provided.

When drain hose routing changes are required, be sure to cap all unused openings.

If rerouting hoses - excess length should be cut off so that no sagging loops will collect

and hold condensate, which will cause the furnace to not operate.

1

2

3

4

5

3

4

2

1

FIGURE 26: Horizontal Left Configuration

20 Johnson Controls Unitary Products

AIRFLOW

HORIZONTAL - RIGHT

INDUCER ROTATED

HORIZONTAL - RIGHT

INDUCER AS RECEIVED

Move rain gutter

hose to this position.

Move pressure

switch hose to

this position.

Change condensate

drain connection to

the 90° fitting

provided.

Move condensate

drain hose to

this position.

Move rain gutter

hose to this position

Change condensate drain

connection to the 90°

fitting provided

Move condensate

drain hose to this position

AIRFLOW

Move pressure

switch hose to

this position.

When drain hose routing changes are required, be sure to cap all un-used openings.

If rerouting hoses - excess length should be cut off so that no sagging loops will collect

and hold condensate, which will cause the furnace to not operate.

2

3

4

1

1

2

3

4

438335-UIM-B-0509

FIGURE 27: Horizontal Right Configuration

Johnson Controls Unitary Products 21

438335-UIM-B-0509

A

A

A

A

STANDARD ELBOW

LONG (SWEEP) ELBOW

SECTION VII: COMBUSTION AIR AND
VENT SYSTEM

COMBUSTION AIR AND VENT SAFETY

This Category IV, dual certified direct vent furnace is designed for resi­dential application. It may be installed without modification to the con­densate system in a basement, garage, equipment room, alcove, attic
or any other indoor location where all required clearance to combusti­bles and other restrictions are met. The combustion air and the venting
system must be installed in accordance with Section 5.3, Air for Com­bustion and Ventilation, of the National Fuel Gas Code Z223.1/NFP A 54
(latest edition), or Sections 7.2, 7.3 or 7.4 of CSA B149.1, National Gas
and Propane Codes (latest edition) or applicable provisions of the local
building code and these instructions.

The VENT SYSTEM must be installed as specified in these instruc­tions for Residential and non-HUD Modular Homes. The direct vent
system is the only configuration that can be installed in a non-HUD
Modular Home.

This furnace may not be common vented with any other appliance,
since it requires separate, properly sized air intake and vent lines.
The furnace shall not be connected to any type of B, BW or L vent
or vent connector, and not connected to any portion of a factory­built or masonry chimney

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

4. All combustion air and vent pipe must conform to American
National Standards Institute (ANSI) and American Society for Test­ing and Materials (ASTM) standards D1785 (Schedule 40 PVC),
D2665 (PVC-DWV), F891 (PVC-DWV Cellular Core), D2261
(ABS-DWV) or F628 (Schedule 40 ABS). Pipe cement and primer
must conform to ASTM Standard D2546 (PVC) or D2235 (ABS). If
ABS pipe is to be used, any joint where ABS pipe is joined to PVC
pipe must be glued with cement that is approved for use with
BOTH materials. Metallic materials must not

be used for venting or

air intake.

5. If a flexible connector is used in the vent system, it must be made
of a material that is resistant to acidic exposure and to at least
225°F (107.2°C) temperature. Flexible connectors are also
allowed in the combustion air pipe.

6. All models are supplied with 2" (5.1 cm) vent connections. When
the pipe must be increased to 3" (7.6 cm) diameter, the transition
from 2" to 3" must be done as close to the furnace as possible. For
upflow models, the transition from 2" to 3" should be done immedi­ately above the furnace. For downflow or horizontal models, the
transition from 2" to 3" pipe should be done immediately after exit­ing the furnace.

7. In Canada, vents shall be certified to ULC S636, Standard for T ype
BH Gas Venting Systems. IPEX System 636 PVC is certified to
this standard.

8. In Canada, the first three feet (91.4 cm) of the vent must be readily
accessible for inspection.

9. For single pipe systems it is recommended to install the combus­tion air coupling provided and install approximately 18” of PVC
pipe on the furnace.

10. Minimum vent length for all models is 5 feet (1.5 m).

TABLE 8:

Maximum Equivalent Pipe Length

When combustion air pipe is installed above a suspended ceiling or
when it passes through a warm and humid space, the pipe must be
insulated with 1/2” Armaflex or other heat resistant type insulation if
two feet or more of pipe is exposed.

Vent piping must be insulated if it will be subjected to freezing tem­peratures such as routing through unheated areas or through an
unused chimney.

COMBUSTION AIR/VENT PIPE SIZING

The size of pipe required will be determined by the furnace model, the
total length of pipe required and the number of elbows required.

Table 8 lists the maximum equivalent length of pipe allowed for each
model of furnace. The equivalent length of elbows is shown in Table 10.
The equivalent length of the vent system is the total length of straight
pipe PLUS the equivalent length of all of the elbows.

The following rules must also be followed:

1. Long radius (sweep) elbows are recommended. Standard elbows
may be used, but since they have a longer equivalent length, they
will reduce the total length of pipe that will be allowed. Short radius
(plumbing vent) elbows are not allowed. The standard dimensions
of the acceptable elbows are shown below.

2. The maximum equivalent length listed in Table 8 is for the vent pip­ing and the air intake piping separately. For example, if the table
allows 65 equivalent feet for a particular model, then the vent can
have 65 equivalent feet of pipe, AND the combustion air intake can
have another 65 equivalent feet of pipe.

3. Three vent terminal elbows (two for the vent and one for the com­bustion air intake) are already accounted for and need not be
included in the equivalent length calculation.

Model Input

BTUH (kW)

Pipe Size

Inches (cm)

length feet (m)

60,000 (17.6) 2 (5.1) 65 (19.8)
60,000 (17.6) 3 (7.6) 90 (27.4)
80,000 (23.4) 2 (5.1) 65 (19.8)

80,000 (23.4) 3 (7.6) 90 (27.4)
100,000 (29.3) 2 (5.1) 30 (9.2)
100,000 (29.3) 3 (7.6) 90 (27.4)
120,000 (35.1) 2 (5.1) 30 (9.2)
120,000 (35.1) 3 (7.6) 90 (27.4)

FIGURE 28:
TABLE 9: Elbow

Dimensions

Dimensions

Elbow "A" Dimension

2" Standard 2-5/16"
3" Standard 3-1/16"
2" Sweep 3-1/4"
3" Sweep 4-1/16"

Dimensions are those required in Standard ASTM D-3311.

Maximum

Equivalent

22 Johnson Controls Unitary Products

438335-UIM-B-0509

TABLE 10:

Example:
An 80,000 BTUH furnace requires 32 feet of pipe and four 90º elbows.

Using 2" pipe and standard elbows, the total equivalent length will be:

32 feet of 2" pipe = 32 equivalent feet
4 - 90º standard 2" elbows = (4x10) = 40 equivalent feet
Total = 72 equivalent feet of 2" pipe

This exceeds the 65 foot maximum equivalent length of 2" pipe allowed
for that model and is thus not

By using sweep elbows, the total equivalent length will be:

32 feet of 2" pipe = 32 equivalent feet
4 - 90º sweep 2" elbows = (4x5) = 20 equivalent feet
Total = 52 equivalent feet of 2" pipe

This is less than the 65 foot maximum equivalent length of 2" pipe
allowed for that model and is thus acceptable.

Alternatively, using 3" pipe and standard elbows, the total equivalent
length will be:

32 feet of 3" pipe = 32 equivalent feet
4 - 90º standard 2" elbows = (4x5) = 40 equivalent feet
Total = 72 equivalent feet of 3" pipe

This is less than the 90 foot maximum equivalent length of 3" pipe
allowed for that model and is thus acceptable.

TABLE 11:

*. Vent pipe size must be increased to 3” diameter after connection to furnace

Equivalent Length of Fittings

Fitting Equivalent Length

2" 90º sweep elbow 5 feet of 2" pipe

2" 45º sweep elbow 2-1/2 feet of 2" pipe
2" 90º standard elbow 10 feet of 2" pipe
2" 45º standard elbow 5 feet of 2" pipe

3" 90º sweep elbow 5 feet of 3" pipe

3" 45º sweep elbow 2-1/2 feet of 3" pipe
3" 90º standard elbow 10 feet of 3" pipe
3" 45º standard elbow 5 feet of 3" pipe

2" corrugated connector 10 feet of 2" pipe
3" corrugated connector 10 feet of 3" pipe

acceptable.

Combustion Air Intake and Vent Connection Size at Furnace

(All Models)

FURNACE VENT CONNECTION SIZES

Furnace Input

Intake Pipe Size 2” (5.1 cm) 3” (7.6 cm)

Vent Pipe Size 2” (5.1 cm) 2” (5.1 cm)

on this model.

40 - 100 MBH

(17.5 - 29.3 kW)

120 - 130 MBH

(35.2 - 39.6 kW)

Accessory concentric vent / intake termination kits 1CT0302 and
1CT0303 are available and approved for use with these furnaces.
Horizontal sidewall vent terminations kits 1HT0901 & 1HT0902 are
also approved for use with these furnaces.

Furnace vent pipe connections are sized for 2” (5.1 cm). pipe. Any
pipe size change must be made outside the furnace casing in a ver­tical pipe section to allow proper drainage of condensate. An offset
using two 45º (degree) elbows will be required for plenum clear­ance when the vent is increased to 3” (7.6 cm).

COMBUSTION AIR AND VENT PIPING ASSEMBLY

The final assembly procedure for the combustion air and vent piping is
as follows:

1. Cut piping to the proper length beginning at the furnace.

2. Deburr the piping inside and outside.

3. Chamfer (bevel) the outer edges of the piping.

4. Dry-fit the vent piping assembly from the furnace to the outside ter­mination checking for proper fit support and slope.

5. Dry-fit the combustion air piping assembly checking for proper fit,
support and slope on the following systems:

a. Sealed combustion air systems from the furnace to the out-

side termination.

b. Ventilated combustion air systems from the furnace to the

attic or crawl space termination.

Solvent cements are flammable and must be used in well-ventilated
areas only. Keep them away from heat, sparks and open flames.
Do not breathe vapors and avoid contact with skin and eyes.

6. Disassemble the combustion air and vent piping, apply cement
primer and the cement per the manufactures instructions. Primer
and cement must conform to ASTM D2564 for PVC, or ASTM
D2235 for ABS piping.

7. All joints must provide a permanent airtight and watertight seal.

8. Support the combustion air and vent piping such that it is angled a
minimum of 1/4” per foot (21 mm/m) so that condensate will flow
back towards the furnace. Piping should be supported with pipe
hangers to prevent sagging.

9. Seal around the openings where the combustion air and / or vent
piping pass through the roof or sidewalls.

COMBUSTION AIR / VENTING

The vent must be installed with the minimum required clearances,
and must comply with local codes and requirements.

Johnson Controls Unitary Products 23

438335-UIM-B-0509

L

E

D

B

V

V

V

X

V

B

V

J

X

B

B

B

V

V

F

V

C

B

X

V

I

V

G

H

A

M

K

OPERABLE

FIXED
CLOSED

VENT TERMINAL

AIR SUPPLY

AREA WHERE TERMINAL IS NOT PERMITTED

FIXED
CLOSED

VENT CLEARANCES

FIGURE 29: Home Layout

Direct Vent Terminal Clearances

A. Clearance above grade, veranda, porch, deck, or

balcony

B. Clearance to window or door that may be opened

Canadian Installations

1,3

US Installation

12” (30.5 cm) 12” (30.5 cm)

12” (30.5 cm) for models 100,000 BTUH (30 kW),
36” (91.4 cm) for models >100,000 BTUH (30 kW).

Two-pipe (direct vent) applic ations: 9” (23 cm) for
models 50,000 BTUH (15 kW), 12” (30.5 cm) for
models >50,000 BTUH (15 kW). ††

2,3

Single-pipe applications: 4 feet (1.2 m).
C. Clearance to permanently closed window 12” (30.5 cm) 12” (30.5 cm)
D. Vertical clearance to ventilated soffit located

above the terminal within a horizontal distance
of 2 feet (61 cm) from the center line of the terminal

E. Clearance to unventilated soffit

F. Clearance to outside corner

12” (30.5 cm) or in accordance with local installation
codes and the requirements of the gas supplier.

12” (30.5 cm) or in accordance with local installation
codes and the requirements of the gas supplier.

12” (30.5 cm) or in accordance with local installation
codes and the requirements of the gas supplier.

12” (30.5 cm) or in accordance with local installation

codes and the requirements of the gas supplier.

12” (30.5 cm) or in accordance with local installation

codes and the requirements of the gas supplier.

12” (30.5 cm) or in accordance with local installation

codes and the requirements of the gas supplier.
G. Clearance to inside corner 3 feet (91.4 cm) 3 feet (91.4 cm)

H. Clearance to each side of center line

extended above meter/regulator assembly

Above a meter/regulator assembly within 3 feet
(91.4 cm) horizontally of the vertical center-line of the
regulator vent outlet to a maximum vertical distance of
15 feet (4.5 m) above the meter/regulator assembly.

I. Clearance to service regulator vent outlet 3 feet (91.4 cm)

J. Clearance to nonmechanical air supply inlet to

building or the combustion air inlet to any other
appliance

12” (30.5 cm) for models 100,000 BTUH (30 kW),
3 feet (91.4 cm) for models >100,000 BTUH (30 kW).

K. Clearance to a mechanical supply inlet 6 feet (1.83 m)
L. Clearance above paved sidewalk or paved

driveway located on public property

7 feet (2.13 m)†

M. Clearance under veranda, porch, deck, or balcony 12” (30.5 cm)‡

1. In accordance with the current CSA B149.1-00, Natural Gas and Propane Installation Code.

2. In accordance with the current ANSI Z223.1 / NFPA 54, National Gas Code.

3. In accordance with the current ANSI Z21.47 * CSA 2.3 American National Standard.

Above a meter/regulator assembly within 3 feet

(91.4 cm) horizontally of the vertical center-line of the

regulator vent outlet to a maximum vertical distance of

15 feet (4.5 m) above the meter/regulator assembly.

3 feet (91.4 cm) or in accordance with local installation

codes and the requirements of the gas supplier.

Two-pipe (direct vent) applic ations: 9” (23 cm) for

models 50,000 BTUH (15 kW), 12” (30.5 cm) for

models >50,000 BTUH (15 kW).

Single-pipe applications: 4 feet (1.2 m).

3 feet (91.4 cm) above if within 10 feet (3 m)

horizontally.

7 feet (2.13 m) or in accordance with local installation

codes and the requirements of the gas supplier.

12” (30.5 cm) or in accordance with local installation

codes and the requirements of the gas supplier

.

† A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.
†† 12” (30.5 cm) up from the bottom edge of the structure for Two-pipe (direct vent) applications per ANSI Z223. 1 / NFPA 54, National Gas Code.
‡ Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor and the distance between the top of the ve nt termina ­tion and the underside of the veranda, porch, or deck is greater than 12” (30 .5 cm) as specified in CSA B149.1-00.
A vent shall not terminate less than 12” (30.5 cm) above a grade level.
Any fresh air or make up inlet for dryer or furnace area is considered to be forced air inlet.
Avoid areas where condensate drippage may cause problems such as above planters, patios, or adjacent to windows where steam may cause fogging.
A terminus of a vent shall be fitted with a cap in accordance with the vent manufacturer’s installation instructions, or in accordance with the installation instructions for a
special venting system.
Responsibility for the provision of proper adequate venting and air supply for application shall rest with the installer.

Vent shall extend high enough above building, or a neighboring obstruction, so that wind from any direction will not create a positive pressure in the vicinity of the vent.

Consideration must be given for degradation of building materials by flue gases. Sidewall termination may require sealing or shielding of building
surfaces with a corrosion resistant material to protect against combustion product corrosion. Consideration must be given to wind direction in
order to prevent flue products and/or condensate from being blown against the building surfaces. If a metal shield is used it must be a stainless
steel material at a minimum dimension of 20” (51 cm). It is recommended that a retaining type collar be used that is attached to the building sur­face to prevent movement of the vent pipe.

24 Johnson Controls Unitary Products

VENT SYSTEM

12” Min.

12” Min.

Maintain 12” minimum clearance
above highest anticipated snow level.
Maximum 24” above roof.

Maintain 12” minimum
clearance above
highest anticipated
snow level.

12” vertical separation
between combustion air
intake and vent.

12” minimum
below overhang

12” minimum
separation between
bottom of
combustion air pipe
and bottom of vent.

Maintain 12”
minimum clearance
above highest
anticipated snow
level or grade,
whichever is higher.

12” MIN.

12” MIN.

OVERHANG

12” Minimum
below overhang

12” Minimum
separation between
bottom of
combustion air
intake and
bottom of vent

Maintain 12”
minimumclearance
above highest
anticipated snow
level or grade,
whichever is higher

VENT

2”
MIN.

COMBUSTION AIR

MIN.
6”

This furnace is certified to be installed with one of two possible vent
configurations.

1. Horizontal vent system. This vent system can be installed com­pletely horizontal or combinations of horizontal, vertical, or offset
using elbows.

2. Vertical vent system. This vent system can be installed completely
vertical or a combination of horizontal, vertical, or offset using
elbows.

VENT APPLICATIONS AND TERMINATION

When selecting the location for a combustion air / vent termination, the
following should be considered:

1. Observe all clearances listed in vent clearances in these instruc­tions.

2. Termination should be positioned where vent vapors will not dam­age plants or shrubs or air conditioning equipment.

3. Termination should be located where it will not be affected by wind
gusts, light snow, airborne leaves or allow recirculation of flue
gases.

4. Termination should be located where it will not be damaged or
exposed to flying stones, balls, etc.

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

6. Horizontal portions of the vent system must slope upwards and be
supported to prevent sagging.

7. Direct vent systems must be installed so the vent and the combus­tion air pipes terminate in the same atmospheric zone. Refer to
Figures 13 or 14.

438335-UIM-B-0509

FIGURE 32: Termination Configuration - 2 Pipe Basement

VENTING MULTIPLE UNITS

Multiple units can be installed in a space or structure as either a single
pipe configuration or a two-pipe configuration.

The combustion air side of the single pipe configuration shown in Figure
29 is referred to in these instructions as ambient combustion air supply.
Follow the instructions for ambient combustion air installations, paying
particular attention to the section on air source from inside the building.
The vent for a single pipe system must be installed as specified in the
venting section of these instructions with the vent terminating as shown
in Figure 29. Each furnace must have a separate vent pipe. Under NO
circumstances can the two vent pipes be tied together.

The combustion air side of the two-pipe configuration shown in Figure
30 can be installed so the combustion air pipe terminates as described
in outdoor combustion air or ventilated combustion air sections in these
instructions. Follow the instructions for outdoor combustion air or venti­lated combustion air and the instructions for installing the vent system
with the vent terminating as shown in Figures 32 or 33. The two-pipe
system must have a separate combustion air pipe and a separate vent
pipe for each furnace. Under NO circumstances can the two combus­tion air or vent pipes be tied together. The combustion air and vent
pipes must terminate in the same atmospheric zone.

FIGURE 30: Termination Configuration - 1 Pipe

FIGURE 31: Termination Configuration - 2 Pipe

Johnson Controls Unitary Products 25

FIGURE 33: Double Horizontal Combustion Air Intake and Vent

Termination

FIGURE 34: Double Vertical Combustion Air Intake and Vent

Termination

438335-UIM-B-0509

Vent pipe cements
into socket just
above top panel

Or vent pipe may be
clamped into outlet
of drain coupling

Connects to
collar on top
of burner box

Vent pipe cements
into socket just
above top panel

Or vent pipe may be
clamped into outlet
of drain coupling

COMBUSTION AIR

COMBUSTION AIR SUPPLY

All installations must comply with Section 5.3, Air for Combustion and
Ventilation of the National Fuel Gas Code, ANSI Z223.1 or Sections

7.2, 7.3 or 7.4 of CAN/CGA B149.1 or .2 Installation Code - latest edi­tions.

This furnace is certified to be installed with one of three possible com­bustion air intake configurations.

1. OUTDOOR COMBUSTION AIR:

This is a direct vent configuration
where the combustion air is supplied through a PVC or ABS pipe
that is connected to the PVC coupling attached to the furnace and
is terminated in the same atmospheric zone as the vent. This type
of installation is approved on all models. Refer to Figure 36.

2. AMBIENT COMBUSTION AIR:

Combustion air is supplied from
the area surrounding the furnace through openings in the furnace
casing. The combustion air and the vent pipes are not terminated
in the same atmospheric zone. Refer to Figure 21 for vent termina­tions. Refer to "Ambient Combustion Air Supply" for proper instal­lation. Refer to Figure 36.

3. VENTILATED COMBUSTION AIR:

Combustion air is supplied
through a PVC or ABS pipe that is connected to the PVC coupling
attached to the burner box and is terminated in a ventilated attic or
crawl space. The combustion air and the vent pipes are not termi­nated in the same atmospheric zone. Refer to Figure 37 for attic
and crawl space termination. Only the combustion air intake may
terminate in the attic. The vent must terminate outside.

Outdoor Combustion Air

Combustion Air Intake/Vent Connections

This installation requires combustion air to be brought in from outdoors.
This requires a properly sized pipe (Shown in Figure 30) that will bring
air in from the outdoors to the furnace combustion air intake collar on
the burner box. The second pipe (Shown in Figure 30) is the furnace
vent pipe.

FIGURE 35: Direct Vent Air Intake Connection and Vent Connection
The combustion air intake pipe should be located either through the

wall (horizontal or side vent) or through the roof (vertical vent). Care
should be taken to locate side vented systems where trees or shrubs
will not block or restrict supply air from entering the terminal.

Also, the terminal assembly should be located as far as possible from a
swimming pool or a location where swimming pool chemicals might be
stored. Be sure the terminal assembly follows the outdoor clearances
listed in Section #1 “Outdoor Air Contaminants.”

Ambient Combustion Air Supply

This type installation will draw the air required for combustion from
within the space surrounding the appliance and from areas or rooms
adjacent to the space surrounding the appliance. This may be from
within the space in a non-confined location or it may be brought into the
furnace area from outdoors through permanent openings or ducts. It is
not piped directly into the furnace. A single, properly sized pipe from the
furnace vent connector to the outdoors must be provided. It is recom­mended that the supplied intake coupling and 18” (46 cm) of pipe be
attached to the furnace to prevent accidental blockage of the combus­tion air intake.

FIGURE 36: Combustion Airflow Path Through The Furnace Casing

This type of installation requires that the supply air to the appli­ance(s) be of a sufficient amount to support all of the appliance(s)
in the area. Operation of a mechanical exhaust, such as an exhaust
fan, kitchen ventilation system, clothes dryer or fireplace may cre­ate conditions requiring special attention to avoid unsatisfactory
operation of gas appliances. A venting problem or a lack of supply
air will result in a hazardous condition, which can cause the appli­ance to soot and generate dangerous levels of CARBON MONOX­IDE, which can lead to serious injury, property damage and / or
death.

3

An unconfined space is not less than 50 cu.ft (1.42 m

) per 1,000 Btu/
hr (0.2928 kW) input rating for all of the appliances installed in that
area.

Rooms communicating directly with the space containing the appli­ances are considered part of the unconfined space, if doors are fur­nished with openings or louvers.

3

A confined space is an area with less than 50 cu.ft (1.42 m

) per 1,000
Btu/hr (0.2928 kW) input rating for all of the appliances installed in that
area. The following must be considered to obtain proper air for combus­tion and ventilation in confined spaces.

Combustion Air Source From Outdoors

The blocking effects of louvers, grilles and screens must be given con­sideration in calculating free area. If the free area of a specific louver or
grille is not known, refer to Table 12, to estimate free area.

Table 12: Estimated Free Area

Wood or Metal

Louvers or Grilles

Screens+

* Do not use less than 1/4” (6.4 mm) mesh
+ Free area of louvers and grille varies widely; the installer should follow

louver or grille manufacturer’s instructions.

Wood 20-25%*
Metal 60-70% *

1/4” (6.4 mm)

mesh or larger 100%

Dampers, Louvers and Grilles (Canada Only)

1. The free area of a supply air opening shall be calculated by sub-

tracting the blockage area of all fixed louvers grilles or screens
from the gross area of the opening.

2. Apertures in a fixed louver, a grille, or screen shall have no dimen-

sion smaller than 1/4” (6.4 mm).

3. A manually operated damper or manually adjustable louvers are

not permitted for use.

4. A automatically operated damper or automatically adjustable lou-

vers shall be interlocked so that the main burner cannot operate
unless either the damper or the louver is in the fully open position.

26 Johnson Controls Unitary Products

When a Category I furnace is removed or replaced, the original

Gable
Vent

Gas
Vent

Soffit
Vent

Ventilated

Attic
Top Above
Insulation

Optional
Inlet (a)

Outlet
Air (a)

Ventilated

Crawl Space

Gas
Water
Heater

Furnace

Soffit
Vent

Gas
Water
Heater

Inlet
Air (a)

Inlet
Air (b)

Furnace

Gas
Vent

Outlet
Air (a)

Outlet
Air (b)

Inlet
Air (a)

Inlet
Air (b)

Gas
Water
Heater

Furnace

Ventilated

Attic

Top Above
Insulation

Gable
Vent

Gas
Vent

venting system may no longer be correctly sized to properly vent
the attached appliances.

An improperly sized vent system can cause CARBON MONOXIDE
to spill into the living space causing personal injury, and or death.

Table 13: Unconfined Space Minimum Area in Square Inch

BTUH Input Rating

60,000

80,000
100,000
120,000

Minimum Free Area in Square Inches

Required for Each Opening

2

60 (387 cm

80 (516 cm
100 (645 cm
120 (742 cm

)

2

)

2

)

2

)

438335-UIM-B-0509

Table 14: Free Area

Minimum Free Area Required for Each Opening

BTUH Input

Rating

60,000

80,000
100,000
120,000

Horizontal Duct

(2,000 BTUH)

2

30 in

(193 cm2) 15 in2 (97 cm2)

2

(258 cm2) 20 in2 (129 cm2)

40 in

2

(322 cm2) 25 in2 (161 cm2)

50 in

2

(387 cm2) 30 in2 (193 cm2)

60 in

EXAMPLE: Determining Free Area.
Appliance 1 Appliance 2 Total Input

100,000 +30,000 = (130,000  4,000) = 32.5 Sq. In. Vertical

Appliance 1 Appliance 2 Total Input

100,000 +30,000 = (130,000  2,000) = 65 Sq. In. Horizontal

Vertical Duct or

Opening to Outside

(4,000 BTUH)

Round Duct

(4,000 BTUH)

5” (13 cm)
5” (13 cm)
6” (15 cm)
7” (18 cm)

FIGURE 37: Outside and Ambient Combustion Air

Air Supply Openings and Ducts

1. An opening may be used in lieu of a duct to provide to provide the
outside air supply to an appliance unless otherwise permitted by
the authority having jurisdiction. The opening shall be located
within 12” (30.5 cm) horizontally from, the burner level of the appli­ance. Refer to “AIR SOURCE FROM OUTDOORS AND VENT
AND SUPPLY AIR SAFETY CHECK” in these instructions for
additional information and safety check procedure.

2. The duct shall be either metal, or a material meeting the class 1
requirements of CAN4-S110 Standard for Air Ducts.

3. The duct shall be least the same cross-sectional area as the free
area of the air supply inlet opening to which it connects.

4. The duct shall terminate within 12” (30.5 cm) above, and within 24”
(61 cm) horizontally from, the burner level of the appliance having
the largest input.

5. A square or rectangular shaped duct shall only be used when the
required free area of the supply opening is 9 in

larger. When a square or rectangular duct is used, its small dimen­sion shall not be less than 3” (7.6 cm).

6. An air inlet supply from outdoors shall be equipped with a means
to prevent the direct entry of rain and wind. Such means shall not
reduce the required free area of the air supply opening.

7. An air supply inlet opening from the outdoors shall be located not
less than 12” (30.5 cm) above the outside grade level.

2

(58.06 cm2) or

Combustion Air Source from Outdoors

1. Two permanent openings, one within 12” (30.5 cm) of the top and
one within 12” (30.5 cm) of bottom of the confined space, Two per­manent openings, shall communicate directly or by means of ducts
with the outdoors, crawl spaces or attic spaces.

2. One permanent openings, commencing within 12” (30.5 cm) of the
top of the enclosure shall be permitted where the equipment has
clearances of at least 1” (2.54 cm) from the sides and back and 6”
(15.2 cm) from the front of the appliance. The opening shall com­municate directly with the outdoors and shall have a minimum free
area of:

3

per 0.879 kW)

a. 1 square in. per 3000 Btu per hour (6.45 cm

of the total input rating of all equipment located in the enclo­sure.

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

space.

3. The duct shall be least the same cross-sectional area as the free
area of the air supply inlet opening to which it connects.

4. The blocking effects of louvers, grilles and screens must be given
consideration in calculating free area. If the free area of a specific
louver or grille is not known. Refer to Table 12.

Johnson Controls Unitary Products 27

438335-UIM-B-0509

12” Min.

12” minimum
between bottom
of air intake and
any material below.

Ventilated Combustion Air

The ventilated attic space or a crawl space from which the combustion
air is taken must comply with the requirements specified in “AIR
SOURCE FROM OUTDOORS” in this instruction or in Section 5.3, Air
for Combustion and Ventilation of the National Fuel Gas Code, ANSI
Z223.1 (latest edition). This type installation requires two properly sized
pipes. One brings combustion air from a properly ventilated attic space
or crawl space and a second pipe that extends from the furnace vent
connection (top right of unit) to the exterior of the building. Refer to
Table 8 for intake pipe sizing, allowable length and elbow usage. Follow
all notes, procedures and required materials in the "COMBUSTION
AIR/VENT PIPE SIZING" section in these instructions when installing
the combustion air pipe from the unit and into a ventilated attic space or
crawl space. DO NOT terminate vent pipe in an Attic or Crawl Space.

CARBON MONOXIDE POISONING HAZARD

Failure to follow the steps outlined below for each appliance connected to the venting system being placed into operation could result in carbon­monxide poisoning or death.

The following steps shall be followed for each appliance connected to the venting system being placed into operation, while all other appliances
connected to the venting system are not in operation:

1. Inspect the venting system for proper size and horizontal pitch. Determine that there is no blockage, restriction, leakage, corrosion or other
deficiencies, which could cause an unsafe condition

2. Close all building doors and windows and all doors.

3. Turn on clothes dryers and TURN ON any exhaust fans, such as range hoods and bathroom exhausts, so they shall operate at maximum
speed. Open the fireplace dampers. Do not operate a summer exhaust fan.

4. Follow the lighting instructions. Place the appliance being inspected in operation. Adjust thermostat so the appliance shall operate contin­uously.

5. Test each appliance (such as a water heater) equipped with a draft hood for spillage (down-draft or no draft) at the draft hood relief opening
after 5 minutes of main burner operation. Appliances that do not have draft hoods need to be checked at the vent pipe as close to the
appliance as possible. Use a combustion analyzer to check the CO

downdraft or inadequate draft condition.

6. After it has been determined that each appliance properly vents when tested as outlined above, return doors, windows, exhaust fans, fire­place dampers and any other gas burning appliance to their normal condition.

7. If improper venting is observed during any of the above tests, a problem exists with either the venting system or the appliance does not
have enough combustion air (Supply Air from outside) to complete combustion. This condition must be corrected before the appliance can
function safely.

NOTE: An unsafe condition exists when the CO reading exceeds 40 ppm and the draft reading is not in excess of - 0.1 in. w.c. (-25 kPa) with all

of the appliance(s) operating at the same time.

8. Any corrections to the venting system and / or to the supply (outside) air system must be in accorda nce with the National Fuel Gas Code
Z223.1 or CAN/CGA B149.1 Natural Gas and Propane Installation Code (latest editions). If the vent system must be resized, follow the
appropriate tables in Appendix G of the above codes or for this appliance.

Ventilated Combustion Air Termination

Refer to Figures 38 for required attic termination for the combustion air
intake pipe. For attic termination, use two 90° elbows with the open end
in a downward position. Be sure to maintain 12” (30.5 cm) clearance
above any insulation, flooring or other material.

A crawl space combustion air installation consists of a straight pipe from
the PVC coupling on the burner box that extends into the crawl space
and terminates with a 1/4” (6.4 mm) mesh screen and no elbows.

and CO levels of each appliance. Use a draft gauge to check for a

2

Specially Engineered Installations

The above requirements shall be permitted to be waived where special
engineering, approved by the authority having jurisdiction, provides an
adequate supply of air for combustion and ventilation.

Be sure to instruct the owner not to block this intake pipe.

VENT BLOWER ROTATION

For ease of venting, the vent blower may be rotated 90° in either direc­tion. For upflow installations the vent may exit through the top or either

FIGURE 38: Attic and Crawl Space Combustion Air Termination

side of the cabinet. For downflow installations, the vent blower must be
rotated so that the vent exits through either side of the cabinet. See Fig­ures 24-27 for details.

28 Johnson Controls Unitary Products

438335-UIM-B-0509

SECTION VIII: START-UP AND
ADJUSTMENTS

The initial start-up of the furnace requires the following additional
procedures:

All electrical connections made in the field and in the factory should
be checked for proper tightness.

When the gas supply is initially connected to the furnace, the gas piping
may be full of air. In order to purge this air, it is recommended that the
ground union be loosened until the odor of gas is detected. When gas is
detected, immediately retighten the union and check for leaks. Allow
five minutes for any gas to dissipate before continuing with the start-up
procedure. Be sure proper ventilation is available to dilute and carry
away any vented gas.

GAS PIPING LEAK CHECK

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 the detection of leaks
to check all connections. A fire or explosion may result causing
property damage, personal injury or loss of life.

Burner ignition may not be satisfactory on first startup due to resid­ual air in the gas line or until gas manifold pressure is adjusted. The
ignition control will make three attempts to light before locking out.

With furnace in operation, check all of the pipe joints, gas valve connec­tions and manual valve connections for leakage using an approved gas
detector, a non-corrosive leak detection fluid or other leak detection
methods. Take appropriate action to stop any leak. If a leak persists,
replace the faulty component.

The furnace and its equipment shutoff valve must be disconnected from
the gas supply during any pressure testing of that system at test pres­sures in excess of 0.5 psig (3.45 kPa).

The furnace must be isolated from the gas supply piping system by
closing the equipment shutoff valve during any pressure testing of the
gas supply system.

IGNITION SYSTEM SEQUENCE

1. Turn the gas supply ON at external valve and main gas valve.

2. Set the thermostat above room temperature to call for heat.

3. System start-up will occur as follows:
a. The induced draft blower motor will start and come up to

speed. Shortly after inducer start-up, the hot surface igniter
will glow for about 17 seconds.

b. After this warm up, the ignition module will energize (open)

the main gas valve.

c. After flame is established, the supply air blower will start in

about 30 seconds.

CALCULATING THE FURNACE INPUT
(NATURAL GAS)

Burner orifices are sized to provide proper input rate using natural gas
with a heating value of 1030 BTU/cu.ft. (38.4 MJ/m
value of your gas is significantly different, it may be necessary to
replace the orifices.

NOTE: DO NOT set manifold pressure less than 3.2” w.c. or more than

3.8” w.c. for natural gas at sea level. If manifold pressure is outside this

range, change main burner orifices.
NOTE: If orifice hole appears damaged or it is suspected to have been

redrilled, check orifice hole with a numbered drill bit of correct size.
Never redrill an orifice. A burr-free and squarely aligned orifice hole is
essential for proper flame characteristics.

DO NOT bottom out gas valve regulator adjusting screw. This can
result in unregulated manifold pressure and result in excess over­fire and heat exchanger failures.

Verify natural gas input rate by clocking meter.

1. Turn off all other gas appliances and pilots.

2. Run furnace for a minimum of 3 minutes in heating operation.

3. Measure time (in sec) for gas meter to complete 1 revolution and
note reading. The 2 cubic feet dial provides a more accurate mea­surement of gas flow.

4. Refer to Table 9 for cubic feet of gas per hour.

5. Multiply cubic feet per hour by heating valve (BTU/cu.ft.) to obtain
input.

If clocked rate does not match the input rate from the unit nameplate.
follow steps in next section to adjust the manifold pressure. Repeat
steps 2 - 5 until correct input is achieved.

3

). If the heating

Be sure to relight any gas appliances that were turned off at the
start of this input check.

Johnson Controls Unitary Products 29

438335-UIM-B-0509

Table 15: Gas Rate (CU FT/HR) at Full Input

Seconds For
1 Revolution

10 360 720 1800 55 65 131 327
11 327 655 1636 56 64 129 321
12 300 600 1500 57 63 126 316
13 277 555 1385 58 62 124 310
14 257 514 1286 59 61 122 305
15 240 480 1200 60 60 120 300
16 225 450 1125 62 58 116 290
17 212 424 1059 64 56 112 281
18 200 400 1000 66 54 109 273
19 189 379 947 68 53 106 265
20 180 360 900 70 51 103 257
21 171 343 857 72 50 100 250
22 164 327 818 74 48 97 243
23 157 313 783 76 47 95 237
24 150 300 750 78 46 92 231
25 144 288 720 80 45 90 225
26 138 277 692 82 44 88 220
27 133 267 667 84 43 86 214
28 129 257 643 86 42 84 209
29 124 248 621 88 41 82 205
30 120 240 600 90 40 80 200
31 116 232 581 92 39 78 196
32 113 225 563 94 38 76 192
33 109 218 545 96 38 75 188
34 106 212 529 98 37 74 184
35 103 206 514 100 36 72 180
36 100 200 500 102 35 71 178

37 97 195 486 104 35 69 173
38 95 189 474 106 34 68 170
39 92 185 462 108 33 67 167
40 90 180 450 110 33 65 164
41 88 176 439 112 32 64 161

42 86 172 429 116 31 62 155
43 84 167 419 120 30 60 150
44 82 164 409 124 29 58 145
45 80 160 400 128 28 56 141
46 78 157 391 133 27 54 135
47 76 153 383 138 26 52 130
48 75 150 375 144 25 50 125
49 73 147 367 150 24 48 120
50 72 144 360 157 23 46 115
51 71 141 355 164 22 44 110
52 69 138 346 171 21 42 105
53 68 136 340 180 20 40 100
54 67 133 333

1 Cu Ft 2 Cu Ft 5 Cu Ft 1 Cu Ft 2 Cu Ft 5 Cu Ft

Size of Test Dial

Seconds For
1 Revolution

Size of Test Dial

30 Johnson Controls Unitary Products

438335-UIM-B-0509

INLET

WRENCH
BOSS

INLET
PRESSURE
PORT

ON OFF
SWITCH

LOW STAGE REGULATOR
ADJUSTMENT

OUTLET

OUTLET
PRESSURE
PORT

VENT
PORT

HIGH STAGE REGULATOR
ADJUSTMENT

U-TUBE
MANOMETER

3.5 IN
WATER
COLUMN
GAS
PRESSURE
SHOWN

GAS
BURNERS

OUTLET
PRESSURE TAP

GAS VALVE

FLAME
SENSOR

1/4” TUBING

MAINIFOLD
PIPE

ADJUSTMENT OF MANIFOLD GAS PRESSURE &
INPUT RATE

Inlet and manifold gas pressure may be measured by connecting the
“U” tube manometer to the gas valve with a piece of tubing. Follow the
appropriate section in the instructions below. Refer to Figures 39 for a
drawing of the locations of the pressure ports on the gas valve.

T urn gas off at the ball valve or gas cock on gas supply line
before the gas valve. Find the pressure ports on the gas
valve marked Out P and In P.

1. The manifold pressure must be taken at the port marked OUT P.

2. The gas line pressure must be taken at the port marked IN P.

3. Using a 3/32” (2.4 mm) Allen wrench, loosen the set screw by turn­ing it 1 turn counter clockwise. DO NOT REMOVE THE SET
SCREW FROM THE PRESSURE PORT.

Read the inlet gas pressure

Connect the positive side of the manometer to the IN P Tap on the gas
valve. Do not connect any tubing to the negative side of the manometer,
as it will reference atmospheric pressure. Refer to Figures 40 for con­nection details.

1. Turn gas and electrical supplies on and follow the operating
instructions to place the unit back in operation.

Table 16: Inlet Gas Pressure Range

INLET GAS PRESSURE RANGE

Natural Gas Propane (LP)

Minimum 4.5” w.c. (1.12 kPa) 8.0” w.c. (1.99 kPa)

Maximum 10.5” w.c. (2.61 kPa) 13.0” w.c. (3.24 kPa)

This gas valve has separate regulator adjustment screws for high fire
and low fire, as shown in Figure 37. The procedure below is used to
adjust either the high fire manifold pressure or the low fire manifold
pressure.

1. Refer to Figures 39 for location of pressure regulator adjustment
cap and adjustment screws on main gas valve.

2. Turn gas and electrical supplies on and follow the operating
instructions to place the unit back in operation.

3. Adjust manifold pressure by adjusting gas valve regulator screw
for the appropriate gas per the following:

Table 17: Nominal Manifold Pressure

NOMINAL MANIFOLD PRESSURE

Natural Gas (High Fire) 3.5" w.c. (0.87 kPa)
Natural Gas (Low Fire) 1.6" w.c. (0.40 kPa)

Propane (LP) Gas (High Fire) 9.8" w.c. (2.488 kPa)

Propane (LP) Gas (Low Fire) 4.0" w.c. (0.99 kPa)

FIGURE 39: Gas Valve

The inlet gas pressure operating range table specifies what the
minimum and maximum gas line pressures must be for the furnace
to operate safely. The gas line pressure MUST BE

• 7” w.c. (1.74 kPA) for Natural Gas

• 11” w.c. (2.74 kPA) for Propane (LP) Gas

in order to obtain the BTU input specified on the rating plate and/or
the nominal manifold pressure specified in these instructions and
on the rating plate.

2. Once the correct gas inlet pressure has been established, see
Table 16, turn the gas valve to OFF and turn the electrical supply
switch to OFF; then remove the flexible tubing from the gas valve
pressure tap and tighten the pressure tap plug using the 3/32” (2.4
mm) Allen wrench.

3. Turn the electrical and gas supplies back on, and with the burners
in operation, check for gas leakage around the gas valve pressure
port for leakage using an approved non-corrosive gas leak detec­tion fluid, or other non-flammable leak detection methods.

Read the manifold gas pressure

Connect the positive side of the manometer to the adapter previously

a minimum of:

If gas valve regulator is turned in (clockwise), manifold pressure is
increased. If screw is turned out (counterclockwise), manifold pres­sure will decrease.

4. After the manifold pressure has been adjusted, re-calculate the
furnace input to make sure you have not exceeded the specified
input on the rating plate. Refer to “CALCULATING THE FURNACE
INPUT (NATURAL GAS)”.

5. Once the correct BTU (kW) input has been established, turn the
gas valve to OFF and turn the electrical supply switch to OFF; then
remove the flexible tubing from the gas valve pressure tap and
tighten the pressure tap plug using the 3/32” (2.4 mm) Allen
wrench.

6. Turn the electrical and gas supplies back on, and with the burners
in operation, check for gas leakage around the gas valve pressure
port for leakage using an approved non-corrosive gas leak detec­tion fluid, or other non-flammable leak detection methods.

MANIFOLD PRESSURE “U” TUBE CONNECTION
installed in the OUT P Tap on the gas valve. Do not connect any tubing
to the negative side of the manometer, as it will reference atmospheric
pressure. Refer to Figures 40 for connection details.

The cap for the pressure regulator must be removed entirely to gain
access to the adjustment screw. Loosening or tightening the cap
does not adjust the flow of gas.

NOTE: The regulated outlet pressure has been calibrated at the factory.
Additional pressure adjustment should not be necessary. If adjustment
is necessary, set to the following specifications. After adjustment, check
for gas leakage.

Johnson Controls Unitary Products 31

FIGURE 40: Reading Gas Pressure

438335-UIM-B-0509

BLOWER OFF

DELAY JUMPER

HI HEAT DELAY

JUMPER

CONTINUOUS FAN

SPEED JUMPER

COOLING PROFILE JUMPER

BLOWER SPEED

JUMPERS

DEHUMIDISTAT JUMPER

HEAT

DELAY

JUMPER

LOW VOLTAGE

TERMINALS

ADJUSTMENT OF TEMPERATURE RISE

The temperature rise, or temperature difference between the return
air and the supply (heated) air from the furnace, must be within the
range shown on the furnace rating plate and within the application
limitations shown in Table 7 “ELECTRICAL AND PERFORMANCE
DATA”.

The supply air temperature cannot exceed the “Maximum Supply
Air Temperature” specified in these instructions and on the fur­nace rating plate. Under NO circumstances can the furnace be
allowed to operate above the Maximum Supply Air Temperature.
Operating the furnace above the Maximum Supply Air Temperature
will cause premature heat exchanger failure, high levels of Carbon
Monoxide, a fire hazard, personal injury, property damage, and/or
death.

After about 5 minutes of operation, determine the furnace temperature
rise. Take readings of both the return air and the heated air in the ducts,
about six feet (1.83 m) from the furnace where they will not be affected
by radiant heat. Increase the blower speed to decrease the temperature
rise; decrease the blower speed to increase the rise.

VARIABLE SPEED MOTORS

The variable speed motor must be configured so the blower will provide
a sufficient airflow so that the furnace operates with in the temperature
rise range on the rating plate and within the application limitations
shown in Table 7 in these Instructions.

ADJUSTMENT OF FAN CONTROL SETTINGS

Heating Indoor Fan Off Delay

This furnace is equipped with a time-on/time-off heating fan control. The
fan on delay is fixed at 30 seconds. The fan off delay has 4 settings (60,
90, 120 and 180 seconds). The fan off delay is factory set to 120 sec­onds. The fan-off setting must be long enough to adequately cool the
furnace, but not so long that cold air is blown into the heated space. The
fan-off timing may be adjusted by positioning the jumper on two of the
four pins as shown in Figure 41.

FIGURE 41: Furnace Control Board

SECTION IX: SAFETY CONTROLS

CONTROL CIRCUIT FUSE

A 3-amp fuse is provided on the control circuit board to pr otect the 24­volt transformer from overload caused by control circuit wiring errors.
This is an ATO 3, automotive type fuse and is located on the control
board.

BLOWER DOOR SAFETY SWITCH

Main power to the unit must still be interrupted at the main power
disconnect switch before any service or repair work is to be done to
the unit. Do not rely upon the interlock switch as a main power dis­connect.

Blower and burner must never be operated without the blower
panel in place.

This unit is equipped with an electrical interlock switch mounted in the
burner compartment. This switch interrupts all power at the unit when
the panel covering the blower compartment is removed.

Electrical supply to this unit is dependent upon the panel that covers the
blower compartment being in place and properly positioned.

ROLLOUT SWITCH CONTROLS

These controls are mounted on the burner assembly. If the temperature
in the area surrounding burner exceeds its set point, the gas valve is
de-energized. The operation of this control indicates a malfunction in
the combustion air blower, heat exchanger or a blocked vent pipe con­nection. Corrective action is required. These are manual reset controls
that must be reset before operation can continue.

PRESSURE SWITCHES

This furnace is supplied with three pressure switches, which monitor the
flow through the combustion air/vent piping and condensate drain sys­tem. These switches de-energize the gas valve if any of the following
conditions are present. Refer to SECTION VI, "CONDENSATE PIPING
AND FURNACE VENTING CONFIGURATION" for tubing connections.

1. Blockage of vent piping or terminal.

2. Failure of combustion air blower motor.

3. Blockage of combustion air piping or terminals.

4. Blockage of condensate drain piping.

32 Johnson Controls Unitary Products

438335-UIM-B-0509

LIMIT CONTROLS

There is a high temperature limit control located on the furnace vesti­bule panel near the gas valve. This is an automatic reset control that
provides over temperature protection due to reduced airflow. This may
be caused by:

1. A dirty filter.

2. If the indoor fan motor should fail.

3. Too many supply or return registers closed or blocked off.
The control module will lockout if the limit trips 5 consecutive times.

If this occurs, control will reset & try ignition again after 1 hour.

SEQUENCE OF OPERATION

Heating and Cooling Airflow

The heating and the cooling airflows are preset at the factory. The heat­ing airflow is set to the maximum CFM. The cooling airflow is set to pro­vide 90 percent of the maximum CFM. The heating and cooling airflows
must be field adjusted to match the HVAC system at installation. See
Table 17 for the HEAT, COOL and ADJ jumper settings to use for spe­cific airflows.

CFM Board - Delay Taps Selection

The set of jumper pins on the control board labeled DELAY are used to
set the delay profiles for the furnace. These can be chosen so as to
maximize the comfort and sound levels for various regions of the coun­try.

Tap A is the default profile. It provides a 30-second ramp-up from zero
airflow to full capacity and a 30-second ramp-down from full capacity
back to zero airflow. Whenever there is a change in airflow mode, such
as from low heat to high heat, the motor will take 30 seconds to ramp
from one speed to the other.

Tap B is the humid profile. This profile is best-suited for installations
where the humidity is frequently very high during cooling season, such
as in the southern part of the country. On a call for cooling, the blower
will ramp up to 50% of full capacity and will stay there for two minutes,
then will ramp up to 82% of full capacity and will stay there for five min­utes, and then will ramp up to full capacity, where it will stay until the
wall thermostat is satisfied. In every case, it will take the motor 30 sec­onds to ramp from one speed to another.

Tap C is the dry profile. This profile is best suited to parts of the country
where excessive humidity is not generally a problem, where the sum­mer months are usually dry. On a call for cooling the motor will ramp up
to full capacity and will stay there until the thermostat is satisfied. At the
end of the cooling cycle, the blower will ramp down to 50% of full capac­ity where it will stay for 60 seconds. Then it will ramp down to zero. In
every case, it will take the motor 30 seconds to ramp from one speed to
another.

Tap D is the normal profile, best suited for most of the country, where
neither excessive humidity nor extremely dry conditions are the norm.
On a call for cooling, the motor will ramp up to 63% of full capacity and
will stay there for 90 seconds, then will ramp up to full capacity. At the
end of the cooling cycle, the motor will ramp down to 63% of full capac­ity and will stay there for 30 seconds, then will ramp down to zero. In
every case, it will take the motor 30 seconds to ramp from one speed to
another.

Continuous Blower Operation

The blower will run continuously whenever the wall thermostat fan
switch is in the ON position. The furnace blower will run at the speed
selected on the FAN SPEED jumpers on the main control board
(HI COOL, LO COOL, HI HEAT or LO HEAT). When the jumper is in the
VS G position, the blower will run at 50% of the high cool speed.

Intermittent Blower Cooling

On cooling/ heating thermostats with a fan switch, when the fan switch
is set in the auto position and the thermostat calls for cooling, a circuit is
completed between the R, Y and G terminals. The motor is energized
through the Y1 cool terminal and runs on the speed selected on the
COOL tap of the control board. The fan off setting is fixed at 60 seconds
for SEER enhancement. The control board can accommodate two­stage cooling. When a two-stage cool thermostat is connected to the Y1
and Y2 terminals on the board, the blower will operate on LOW COOL
speed when Y1 is energized and on HI COOL speed when Y1 and Y2
are energized.

Intermittent Blower Heating

On cooling/ heating thermostats with a fan switch, when the fan switch
is set in the auto position and the thermostat calls for heating, a circuit is
completed between the R and W terminals. The indoor fan motor is
energized through the W1 heat terminal and runs on the speed selected
on the HEAT tap of the control board.

Humidistat

When a humidistat is installed in the system, the “Humidistat Installed?”
jumper on the control board should be moved to the YES position.
The cooling CFM will then be reduced by 15% whenever the humidistat
indicates high humidity.

Heating Cycle

When the thermostat switch is set on HEAT and the fan is set on AUTO,
and there is a call for heat, a circuit is completed between terminals R
and W of the thermostat. When the proper amount of combustion air is
being provided, the pressure switch will close, the ignition control pro­vides a 17-second ignitor warm-up period, the gas valve then opens,
the gas starts to flow, ignition occurs and the flame sensor begins its
sensing function. The blower motor will energize 30 seconds after the
gas valve opens, if a flame is detected. Normal furnace operation will
continue until the thermostat circuit between R and W is opened, which
causes the ignition system and gas valve to de-energize and the burner
flames to be extinguished. The vent motor will operate for 15 seconds
and the blower motor will operate for the amount of time set by the fan­off delay jumper located on the control board. See Figure 36. The heat­ing cycle is now complete, and ready for the start of the next heating
cycle.

If the flame is not detected within 7 seconds of the gas valve opening,
the gas valve is shut off and a retry operation begins. Also, if the flame
is lost for 2 seconds during the 10-second stabilization period, the gas
valve is shut off and a retry operation begins. During a retry operation,
the vent motor starts a 15 second inter-purge and the ignitor warm-up
time is extended to 27 seconds. If the flame is established for more than
10 seconds after ignition during a retry, the control will clear the ignition
attempt (retry) counter. If three retries occur during a call for heat, the
furnace will shut down for one hour. If at the end of the one hour shut
down there is a call for heat, the furnace will initiate a normal start cycle.
If the problem has not been corrected the furnace will again lockout
after three retries.

A momentary loss of gas supply, flame blowout, or a faulty flame probe
circuit will result in a disruption in the flame and be sensed within 1.0
seconds. The gas valve will de-energize and the control will begin a
recycle operation. A normal ignition sequence will begin after a 15 sec­ond inter-purge. If during the five recycles the gas supply does not
return, or the fault condition is not corrected the ignition control will lock­out for 60 minutes.

During burner operation, a momentary loss of power for 50 milliseconds
or longer will de-energize the gas valve. When the power is restored,
the gas valve will remain de-energized and the ignition sequence will
immediately restart.

Johnson Controls Unitary Products 33

438335-UIM-B-0509

Hot Surface Ignition System

HOT SURFACE IGNITION SYSTEM
Do not attempt to light this furnace by hand (with a
match or any other means). There may be a potential
shock hazard from the components of the hot surface
ignition system. The furnace can only be lit automatically
by its hot surface ignition system.

TROUBLESHOOTING

The following visual checks should be made before troubleshooting:

1. Check to see that the power to the furnace and the ignition control
module is ON.

2. The manual shut-off valves in the gas line to the furnace must be
open.

3. Make sure all wiring connections are secure.

4. Review the sequence of operation. Start the system by setting the
thermostat above the room temperature. Observe the system’s
response. Then use the troubleshooting section in this manual to
check the system’s operation.

Never bypass any safety control to allow furnace opera­tion. To do so will allow furnace to operate under poten­tially hazardous conditions.
Do not try to repair controls. Replace defective controls
with UPG Source 1 Parts.

Never adjust pressure switch to allow furnace operation.

FURNACE CONTROL DIAGNOSTICS

The furnace has built-in, self-diagnostic capability. If a system problem
occurs, a blinking LED can flash red, green or amber to indicate various
conditions.

The control continuously monitors its own operation and the operation
of the system. If a failure occurs, the LED will indicate the failure code. If
the failure is internal to the control, the light will stay on continuously. In
this case, the entire control should be replaced, as the control is not
field repairable.

Flash sequence codes 1 through 11 are as follows: LED will turn ON for
1/4 second and OFF for 1/4 second. This pattern will be repeated the
number of times equal to the code. For example, six ON flashes equals
a number 6 fault code. All flash code sequences are broken by a 2 sec­ond OFF period.

SLOW GREEN FLASH: Normal operation.
SLOW AMBER FLASH: Normal operation with call for heat.
RAPID RED FLASH: Twinning error, incorrect 24V phasing. Check

twinning wiring.
RAPID AMBER FLASH: Flame sense current is below 1.5 microamps.

Check and clean flame sensor. Check for proper gas flow. Verify that
current is greater than 1.5 microamps at flame current test pad.

4 AMBER FLASHES: The control is receiving a “Y” signal from the
thermostat without a “G” signal, indicating improper thermostat wiring.

1 RED FLASH: This indicates that flame was sensed when there was
not a call for heat. The control will turn on both the inducer motor and
supply air blower. A gas valve that leaks or is slow closing would typi­cally cause this fault.

2 RED FLASHES: This indicates that the normally open pressure
switch contacts are stuck in the closed position. The control confirms
these contacts are open at the beginning of each heat cycle. This would
indicate a faulty pressure switch or miswiring.

3 RED FLASHES: This indicates the normally open pressure switch
contact did not close after the inducer was energized. This could be
caused by a number of problems: faulty inducer, blocked vent pipe, bro­ken pressure switch hose or faulty pressure switch.

4 RED FLASHES: This indicates that the main limit switch has opened
its normally closed contacts. The control will operate the supply air
blower and inducer. This condition may be caused by: dirty filter,
improperly sized duct system, incorrect blower speed setting, incorrect
firing rate or faulty blower motor. Also, this fault code could be caused
by a blown fuse located on the control board.

5 RED FLASHES: This fault is indicated if the normally closed contacts
in the rollout switch opens. The rollout control is manually reset. If it has
opened, check for proper combustion air, proper inducer operation, and
primary heat exchanger failure or burner problem. Be sure to reset the
switch and cycle power (24 VAC) to the control after correcting the fail­ure condition. Also, this fault code could be caused by a blown fuse
located on the control board.

6 RED FLASHES: This indicates that after the unit was operating, the
pressure switch opened 4 times during the call for heat. If the main
blower is in a “Delay on” mode, it will complete it, and any subsequent
delay off period. The furnace will lock out for one hour and then restart.

7 RED FLASHES: This fault code indicates that the flame could not be
established. This no-light condition occurred 3 times (2 retries) during
the call for heat before locking out. Low gas pressure, faulty gas valve,
dirty or faulty flame sensor, faulty hot surface ignitor or burner problem
may cause this. The furnace will lock out for one hour and then restart.

8 RED FLASHES: This fault is indicated if the flame is lost 5 times (4
recycles) during the heating cycle. This could be caused by low gas
pressure, dirty or faulty flame sensor or faulty gas valve. The furnace
will lock out for one hour and then restart.

9 RED F

problem. Both heating and cooling operations will be affected. Check
polarity at furnace and branch. Check furnace grounding. Check that
flame probe is not shorted to chassis.

10 RED FLASHES: Flame sensed with no call for heat. Check gas
valve and gas valve wiring.

11 RED FLA SHES: This indicates that a primary or auxiliary limit switch
has opened its normally-closed contacts and has remained open for
more than five minutes. This condition is usually caused by a failed
blower motor or blower wheel. Cycle power (24 VAC) to the control to
reset the hard lockout condition after correcting the failure condition.

12 RED FLASHES: This code indicates an open igniter circuit, which
could be a disconnected or loose wire or a cracked or broken igniter.

STEADY ON RED: Control failure. Replace control board.
60-MINUTE AUTOMATIC RESET FROM LOCKOUT: This control

includes a “watchdog” type circuit that will reset from a lockout condition
after 60 minutes. Operational faults 6, 7, 8 will be reset. This provides
protection to an unoccupied structure if a temporary condition exists
causing a furnace malfunction. An example would be a low incoming
gas supply pressure preventing unit operation. When the gas pressure
is restored, at some point the “watchdog” would restart the unit and pro­vide heat for the house.

NOTE: If a flame is detected the control flashes the LED for 1/8 of a
second and then enters a flame stabilization period.

LASHES: Indicates reversed line voltage polarity or grounding

IGNITION CONTROL FLAME SENSE LEVELS

Normal flame sense current is approximately

3.7 microamps DC (µa)

Low flame signal warning starts at 1.5 microamps.

Low flame signal control lockout point is

0.1 microamps DC (µa)

34 Johnson Controls Unitary Products

438335-UIM-B-0509

Thermostat Calling for Heat

Thermostat Satisfied

(Seconds)

THERMOSTAT

INDUCER

IGNITOR

MAIN VALVE

HUMIDIFIER

ELECTRONIC
AIR CLEANER

CIRCULATING
BLOWER

OFF

OFF

OFF

OFF

OFF

OFF

OFF

ON

ON

ON

ON

OFF

OFF

OFF

OFF

ON

ON

ON

OFF

OFF

OFF

OFF

OFF

OFF

OFF

15
Sec.
Post
Purge

Fan on Delay
30 Seconds

0

2

17 22

52

0

60, 90, 120, 180 SEC.
Selectable Fan Off Delay

DIAGNOSTIC FAULT CODE STORAGE AND
RETRIEVAL

The control in this furnace is equipped with memory that will store up to
five error codes to allow a service technician to diagnose problems
more easily. This memory will be retained even if power to the furnace
is lost. This feature should only be used by a qualified service tech-

nician.

If more than five error codes have occurred since the last reset, only the
five most recent will be retained. The furnace control board has a but­ton, labeled LAST ERROR that is used to retrieve error codes. This
function will only work if there are no active thermostat signals. So any
call for heating, cooling or continuous fan must be terminated before
attempting to retrieve error codes.

To retrieve the error codes, push the LAST ERROR button. The LED on
the control will then flash the error codes that are in memory, starting
with the most recent. There will be a two-second pause between each
flash code. After the error codes have all been displayed, the LED will
resume the normal slow green flash after a five second pause. To
repeat the series of error codes, push the button again.

If there are no error codes in memory, the LED will flash two green
flashes. To clear the memory, push the LAST ERROR button and hold it
for more than five seconds. The LED will flash three green flashes when
the memory has been cleared, then will resume the normal slow green
flash after a five-second pause.

FIGURE 42: Furnace Control Event Schedule

Johnson Controls Unitary Products 35

438335-UIM-B-0509

SECTION X: REPLACEMENT PARTS LIST

DESCRIPTION

MOTOR

MOTOR, DIRECT DRIVE BLOWER
BLOWER, COMBUSTION 2-STAGE

ELECTRICAL

CAPACITOR, RUN
SWITCH, LIMIT
CONTROL, FURNACE 2-STAGE VS

IGNITER
SENSOR, FLAME
SWITCHES, PRESSURE
SWITCH, DOOR

TRANSFORMER
VALVE, GAS 2-STAGE
CONTROL, TEMPERATURE

AIR MOVING

HOUSING, BLOWER
WHEEL, BLOWER

FABRICATED PARTS

RESTRICTOR, COMBUSTION BLOWER
BURNER, MAIN GAS
BRACKET, IGNITER
SHELF, BLOWER
RAIL, BLOWER (2 Req’d)
BRACKET, BLOWER TRACK (2 Req’d)
HEAT EXCHANGER ASS’Y

DESCRIPTION

FABRICATED PARTS Continued

MANIFOLD, GAS
PAN, BOTTOM
PANEL, TOP
PANEL, DOOR (2 Req’d)
PANEL, BLOCKOFF

MISCELLANEOUS

ORIFICE, BURNER (Natural #45)
SIGHT GLASS, OVAL (2 Req’d)
GASKET, FOAM (Door) (1.5 ft req’d)
PAN, CONDENSATE
BRACKET, DOOR
HARNESS, WIRING
FERRULE (3 Req’d)
GROMMET (3 Req’d)
MOTOR MOUNT
TUBING, SILICON
HOSE, RAIN GUTTER
HOSE, CONDENSATE
PLUG, SEAL, 7/8”
PLUG, SEAL, 2-3/8”
PLUG, VENT PIPE
BAG, PARTS
KNOB, QUARTER TURN (4 Req’d)
DIAGRAM, WIRING 2-STAGE VS

REPLACEMENT PART CONTACT INFORMATION

This is a generic parts list. To request a complete parts list, refer to the contact information below:

• Visit our website at www.source1parts.com for the following info rmation:

1. Search for a part or browse the catalog.

2. Find a dealer or distributor.

3. Customer Service contact information.
a. Click on the “Brand Links” button

b. Click on the “Customer Service” button

• You can contact us by mail. Just send a written request to:

Johnson Controls Unitary Products

Consumer Relations

5005 York Drive

Norman, OK 73069

36 Johnson Controls Unitary Products

SECTION XI: WIRING DIAGRAM

438335-UIM-B-0509

FIGURE 43: Wiring Diagram

Johnson Controls Unitary Products 37

NOTES

Subject to change without notice. Published in U.S.A 438335-UIM-B-0509
Copyright © 2009 by Johnson Controls, Inc. All rights reserved. Supersedes: 438335-UIM-A-0209

Johnson Controls Unitary Products

5005 York Drive

Norman, OK 73069