Trane UD2B060ACV32A Series Assembly instructions

Variable Speed, 2-Stage Communicating or 24V
Upflow/ Horizontal and Downflow / Horizontal,
Gas-Fired Furnaces, “Fan Assisted
Combustion System”
A341789P11
Installer’s Guide
Downflow / Horizontal 2
Upflow / Horizontal 1
For VENT SIZING INFORMATION see:
USA —
National Fuel Gas Code........... ANSI Z223.1/NFPA 54 (latest version)
CANADA —
Natural Gas Installation Code ........CAN/CGA-B149.1 (latest version)
Propane Installation Code...............CAN/CGA-B149.2 (latest version)
USA/CANADA ALTERNATE —
Category I Venting Guide ...........Pub. No. 18-CH23D1 (latest version)
1Horizontal Conversion for these furnaces may be left or right side rotation.
2Horizontal Conversion for these furnaces may be left or right side rotation (Important: See venting applications, page 8).
ALL phases of this installation must comply with NATIONAL, STATE AND LOCAL CODES
IMPORTANT — This Document is customer property and is to remain with this unit.
Please return to service information pack upon completion of work.
*First letter may be “A” or “T”
*UD2B060ACV32A
*UD2B080ACV32A
*UD2C080ACV42A
*UD2B100ACV32A
*UD2C100ACV52A
*UD2D120ACV52A
*UD2D140ACV52A
*DD2B060ACV32A
*DD2B080ACV32A
*DD2C100ACV52A
*DD2D120ACV52A
*DD2-ACV
*UD2-ACV
Left Right
18- CD32D1- 3
18- CD32D1- 3

© 2011 Trane All Rights Reserved 18-CD32D1-3
Installer’s Guide
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 carbon monoxide
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. Seal any unused openings in the venting system.
2. Inspect the venting system for proper size and
horizontal pitch, as required in the National Fuel Gas
Code, ANSI Z223.1/NFPA 54 or the CAN/CGA B149
Installation Codes and these instructions. Determine
that there is no blockage or restriction, leakage,
corrosion and other deficiencies which could cause an
unsafe condition.
3. As far as practical, close all building doors and
windows and all doors between the space in which the
appliance(s) connected to the venting system are
located and other deficiencies which could cause an
unsafe condition.
4. Close fireplace dampers.
5. Turn on clothes dryers and any appliance not
connected to the venting system. Turn on any exhaust
fans, such as range hoods and bathroom exhausts, so
they are operating at maximum speed. Do not operate
a summer exhaust fan.
6. Follow the lighting instructions. Place the appliance
being inspected into operation. Adjust the thermostat
so appliance is operating continuously.
7. If improper venting is observed during any of the above
tests, the venting system must be corrected in
accordance with the National Fuel Gas Code,
ANSI Z221.1/NFPA 54 and/or CAN/CGA B149
Installation Codes.
8. After it has been determined that each appliance
connected to the venting system properly vents where
tested as outlined above, return doors, windows,
exhaust fans, fireplace dampers and any other gas-fired
burning appliance to their previous conditions of use.
▲
WARNING
!
Failure to follow safety warnings exactly, could result
in a fire or explosion causing property damage,
personal injury or loss of life.
— Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any
other appliance.
— WHAT TO DO IF YOU SMELL GAS
•Do not try to light any appliance.
•Do not touch any electrical switch;
do not use any phone in your building.
•Immediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s
instructions.
•If you cannot reach your gas supplier,
call the fire department.
— Installation and service must be performed by
a qualified installer, service agency or the gas
supplier.
▲WARNING
!
The following warning complies with State of California law, Proposition 65.
Hazardous Gases!
Exposure to fuel substances or by-products of incomplete
fuel combustion is believed by the state of California to
cause cancer, birth defects, or other reproductive harm.
▲
WARNING
!
▲WARNING
!
EXPLOSION HAZARD
Propane gas is heavier than air and may collect in
any low areas or confined spaces. In addition, odor-
ant fade may make the gas undetectable except with
a warning device. If the gas furnace is installed in a
basement, an excavated area or a confined space, it
is strongly recommended to contact a gas supplier
to install a gas detection warning device in case of a
gas leak. Failure to follow this warning could result in
property damage, personal injury or death.
NOTE: The manufacturer of your furnace does NOT test
any detectors and makes no representations regarding
any brand or type of detector.
▲WARNING
!
SAFETY HAZARD
This information is intended for use by individuals
posessing adequate backgrounds of electrical and
mechanical experience. Any attempt to repair a cen-
tral air conditioning product may result in property
damage, personal injury, or death. The manufacturer
or seller cannot be responsible for the interpretation
of this information, not can it assume any liability in
connection with its use. Failure to follow this warn-
ing could result in property damage, personal injury
or death.
▲CAUTION
!
Sharp Edge Hazard. Be careful of sharp edges on
equipment or any cuts made on sheet metal while
installing or servicing. Personal injury may result.
Safety signal words are used to designate a degree or level
of seriousness associated with a particular hazard. The sig-
nal words for safety markings are WARNING and CAUTION.
a. WARNING indicates a potentially hazardous situation
which, if not avoided, could result in death or serious
injury.
b. CAUTION indicates a potentially hazardous situation
which, if not avoided, may result in minor or moderate
injury. It is also used to alert against unsafe practices
and hazards involving only property damage.

18-CD32D1-3 3
Installer’s Guide
Safety Section 2
Installation Instructions 4
General Installation Instructions 4
Location and Clearances 4
Outline Drawing 5-6
Upflow Installation 7
Downflow Installation 7
Horizontal Installation 7
Air for Combustion and Ventilation 9
Duct Connections 10
Return Air Filters 12
General Venting Instructions 15
Venting into a Masonry Chimney 15
Electrical Connections 17
Field Wiring Diagrams 17-20
Gas Piping 22
Combustion and Input Check 22
Gas Valve Adjustment 23
High Altitude Derate 24
Start Up and Adjustment 25
Preliminary Inspections 25
Lighting Instructions 25
User Interface menu - Communicating Mode 27
User Interface menu - 24 VAC Mode 28
Sequence Of Operation 29
Control and Safety Switch Adjustment 32
Conditions Affecting Furnace Operation 33
Furnace Alert Codes 35
Contents
The following safety practices and precautions must be
followed during the installation, servicing, and operation of
this furnace.
1. Use only with the type of gas approved for this furnace.
Refer to the furnace rating plate.
2. Install this furnace only in a location and position as
specified in “Location and Clearances” (page 4), of these
instructions.
3. Provide adequate combustion and ventilation air to the
furnace space as specified in “Air for Combustion and
Ventilation” (pages 9), of these instructions.
4. Combustion products must be discharged outdoors.
Connect this furnace to an approved vent system only,
as specified in the “Venting” section (pages 15-16), of
these instructions.
5. Never test for gas leaks with an open flame. Use a
commercially available soap solution made specifically
for the detection of leaks to check all connections, as
specified in “Gas Piping” (page 22) of these instruc-
tions.
6. Always install the furnace to operate within the fur-
nace’s intended temperature-rise range with a duct sys-
tem which has an external static pressure within the
allowable range, as specified on the unit rating plate.
Airflow with temperature rise for cfm versus static is
shown in the Service Facts accompanying this furnace.
7. When a furnace is installed so that supply ducts carry
air circulated by the furnace to areas outside the space
containing the furnace, the return air shall also be
handled by a duct(s) sealed to the furnace casing and
terminating outside the space containing the furnace.
8. A gas-fired furnace for installation in a residential
garage must be installed as specified in “Location and
Clearances” section (page 4) of these instructions.
▲CAUTION
!
Do not install the furnace in a corrosive or contaminated
atmosphere.
▲WARNING
!
SAFETY HAZARD
Do not install the furnace directly on carpeting, tile or
other combustible material other than wood flooring.
For vertical downflow application, subbase (BAY-
BASE205) must be used between the furnace and
combustible flooring. When the downflow furnace is
installed vertically with a cased coil, a subbase is not
required. Failure to follow this warning could result
in property damage, personal injury or death.
▲CAUTION
!
LABELING WIRES!
Label all wires prior to disconnection when servicing con-
trols. Wiring errors can cause improper and dangerous
operation. Verify Proper Operation after servicing.
▲CAUTION
!
To prevent shortening its service life, the Furnace
should NOT be used as a “Construction Heater”
during the finishing phases of construction until the
requirements listed in item 9, a-i of the safety sec-
tion of this publication have been met. Condensate
in the presence of chlorides and fluorides from paint,
varnish, stains, adhesives, cleaning compounds,
and cement create a corrosive condition which may
cause rapid deterioration of the heat exchanger.
▲WARNING
!
SAFETY HAZARD
DO NOT USE SEMI-RIGID METALLIC GAS CONNEC-
TORS (flexible GAS lines) within the Furnace cabinet.
Failure to follow this warning could result in property
damage, personal injury or death.
▲WARNING
!
EXPLOSION HAZARD
NEVER USE AN OPEN FLAME TO DETECT GAS
LEAKS. EXPLOSIVE CONDITIONS MAY OCCUR.
USE A LEAK TEST SOLUTION OR OTHER AP-
PROVED METHODS FOR LEAK TESTING. FAIL-
URE TO FOLLOW THIS WARNING COULD RESULT
IN PROPERTY DAMAGE, PERSONAL INJURY OR
DEATH.

4 18-CD32D1-3
Installer’s Guide
9. The furnace may be used for temporary heating of
buildings or structures under construction only when
the following conditions have been met:
a. The furnace venting system must be complete and
installed per manufacturer’s instructions.
b. The furnace is controlled only by a room thermostat
(no field jumpers).
c. The furnace return air duct must be complete and
sealed to the furnace and clean air filters are in
place.
d. The furnace input rate and temperature rise must
be verified to be within nameplate marking.
e. 100% of the furnace combustion air require-
ment must come from outside the structure.
f. The furnace return air temperature range is be-
tween 55 and 80 degrees Fahrenheit.
g. Clean the furnace, duct work, and components upon
substantial completion of the construction process,
and verify furnace operating conditions including
ignition, input rate, temperature rise and venting,
according to the manufacturer’s instructions.
10. This product must be gas piped by a Licensed Plumber
or Gas Fitter in the Commonwealth of Massachusetts.
▲WARNING
!
FIRE OR EXPLOSION HAZARD
Failure to follow the safety warnings exactly could result
in serious injury, death or property damage. Improper ser-
vicing could result in dangerous operation, serious injury,
death, or property damage.
GENERAL INSTALLATION INSTRUCTIONS
The manufacturer assumes no responsibility for equipment
installed in violation of any code or regulation.
This furnace can be configured for Communicating
or 24 VAC modes. Using fully Communicating or 24
VAC modes, the furnace can support single or multi
stage heat pump, AC, or heating only applications.
Combined with a communicating Comfort Control
only, the furnace will support a single stage 24 VAC
cooling outdoor unit only.
It is recommended that Manual J of the Air Conditioning
Contractors Association (ACCA) or A.R.I. 230 be followed
in estimating heating requirements. When estimating
heating requirements for installation at Altitudes above
2000 ft., remember the gas input must be reduced (See GAS
INPUT ADJUSTMENT).
Material in this shipment has been inspected at the
factory and released to the transportation agency
without known damage. Inspect exterior of carton
for evidence of rough handling in shipment. Unpack
carefully after moving equipment to approximate
location. If damage to contents is found, report the
damage immediately to the delivering agency.
Codes and local utility requirements governing the instal-
lation of gas fired equipment, wiring, plumbing, and flue
connections must be adhered to. In the absence of local
codes, the installation must conform with latest edition of
the National Fuel Gas Code ANSI Z223.1 • National Instal-
lation Code, CAN/CGA B149.1. The latest code may be
obtained from the American Gas Association Laboratories,
400 N. Capitol St. NW, Washington D.C. 20001.
1-800-699-9277 or www.aga.org
These furnaces have been classified as Fan Assisted Com-
bustion system CATEGORY I furnaces as required by
ANSI Z21.47 “latest edition” and CAN/CGA 2.3. Therefore
they do not require any special provisions for venting other
than what is indicated in these instructions. (Category I
defined on page 15).
▲WARNING
!
SAFETY HAZARD
These furnaces are not approved or intended for installa-
tion in manufactured (mobile) housing, trailers, or rec-
reational vehicles. Failure to follow this warning could
result in property damage, personal injury, or death.
LOCATION AND CLEARANCES
The location of the furnace is normally selected by the
architect, the builder, or the installer. However, before the
furnace is moved into place, be sure to consider the follow-
ing requirements:
1. Is the location selected as near the chimney or vent and
as centralized for heat distribution as practical?
2. Do all clearances between the furnace and enclosure
equal or exceed the minimums stated in Clearance
Table on the Outline Drawings.
3. Is there sufficient space for servicing the furnace and
other equipment? A minimum of 24 inches front acces-
sibility to the furnace must be provided. Any access
door or panel must permit removal of the largest com-
ponent.
4. Are there at least 3 inches of clearance between the
furnace combustion air openings in the front panel and
any closed panel or door provided?
5. Are the ventilation and combustion air openings large
enough and will they remain unobstructed? If outside
air is used, are the openings set above the highest snow
accumulation level? (See the Air for Combustion and
Ventilation section.)
6. Allow sufficient height in supply plenum above the
furnace to provide for cooling coil installation, if the
cooling coil is not installed at the time of this furnace
installation.
7. A furnace shall be installed so electrical components
are protected from water.
8. If the furnace is installed in a residential garage, it
must be installed so that the burners, and the ignition
source are located not less than 18 inches above the
floor and the furnace must be located or protected to
avoid physical damage from vehicles.

18-CD32D1-3 5
Installer’s Guide
*UD2B060ACV32A *UD2B080ACV32A *UD2B100ACV32A *UD2C080ACV42A *UD2C100ACV52A
*UD2D120ACV52A *UD2D140ACV52A
From Dwg. C341699 Rev. 9
*UD-ACV OUTLINE DRAWING
(ALL DIMENSIONS ARE IN INCHES)

6 18-CD32D1-3
Installer’s Guide
From Dwg. C341700 Rev. 5
*DD2-ACV OUTLINE DRAWING
(ALL DIMENSIONS ARE IN INCHES)
MODEL A B C D
*DD2B060ACV32A *DD2B080ACV32A 17-1/2" 9-5/8" 16-1/4" 16"
*DD2C100ACV52A 21" 13-1/16" 19-3/4" 19-1/2" *DD2D120ACV52A 24-1/2" 15-5/16" 23-1/4" 23"
* - The First Letter May Be "A" or "T"

18-CD32D1-3 7
Installer’s Guide
FURNACE
FRONT
A (width)
B (depth)
C
D
3
UPFLOW
FURNACE
CASED
COIL
SCREWS
(BOTH SIDES)
STANDOFFS
(BOTH SIDES)
STANDOFFS (4) DRILL SCREWS (4)
FOR VERTICAL
INSTALLATIONS:
1
2
UPFLOW INSTALLATION
Standoffs and screws (See Figure 1) are included with the
cased coils for attachment to the furnace. There are clear-
ance alignment holes near the bottom of the coil wrapper.
Drill screws are used to engage the furnace top flanges.
The standoff is inserted into the cabinet alignment hole.
The drill screws are inserted through the standoffs then
screwed into the furnace flange. The coil is always placed
downstream of the furnace airflow. The above instructions
apply only if the coil is on top of an upflow furnace.
DOWNFLOW INSTALLATION
▲WARNING
!
FIRE HAZARD
Do not install the furnace directly on carpeting, tile or
other combustible material other than wood flooring.
For vertical downflow application, subbase (BAY-
BASE205) must be used between the furnace and
combustible flooring. When the downflow furnace is
installed vertically with a cased coil, a subbase is not
required. Failure to follow this warning could result
in property damage, personal injury or death.
REQUIRED FLOOR OPENING: (DOWNFLOW)
See Figure 3 and Table 1
TABLE 1
CABINET
WIDTH
RETURN
DUCT WIDTH
FLOOR OPENING PLENUM OPENING
"A" "B" "C" "D"
17-1/2" 16-1/4" 16-5/8" 20-1/8" 15-5/8" 19-3/8"
21" 19-3/4" 20-1/8" 20-1/8" 19-1/8" 19-3/8"
24-1/2" 23-1/4" 23-5/8" 20-1/8" 22-5/8" 19-3/8"
HORIZONTAL INSTALLATION
The coil and furnace must be fully supported when used in
the horizontal.
Three brackets (with screws) are included with downflow
furnaces for installation to stabilize and secure the furnace
and TXC cased coil in the horizontal position. See Fig-
ure 4.
IMPORTANT:
The 2/4TXC cased coil must be placed downstream in the
supply air of the furnace. In horizontal installations, the
apex of the coil may point either toward or away from the
furnace. See the 2/4TXC coil Installer's Guide for more
details.
The cased coil is secured to the furnace and both the fur-
nace and the cased coil must be properly supported. The
brackets mount using the rear screws on the coil case and
use the screws provided to secure the bracket to the fur-
nace. The remaining bracket is placed as close to center as
possible (horizontally) between the coil case front and the
furnace bottom channel (for downflow/horizontal furnace).
Use four of the screws provided to secure the bracket.
This furnace may be installed in an attic or crawl space in
the horizontal position by placing the furnace on the left or
right side (as viewed from the front in the upright posi-
tion). The horizontal furnace installation in an attic should
be on a service platform large enough to allow for proper
clearances on all sides and service access to the front of
the furnace (See Clearance Table on Outline Drawings and
Figure 5).
If the furnace is suspended using perforated steel strap
(plumber’s strap), it must be supported at all four corners
and in the middle at the front of the furnace. The forward
most screw on the side of the furnace may be used to con-
nect the strapping (See Figure 7). Line contact is only per-
missible between lines formed by the intersection of the top
and two sides of the furnace casing and the building joists,
studs, or framing.
CASED COIL CONNECTION
BRACKET FOR DOWNFLOW FUR-
NACE IN HORIZONTAL
4
5
Typical Upflow/Horizontal Attic Installation

8 18-CD32D1-3
Installer’s Guide
6
Airflow
Airflow
Airflow
Airflow
Airflow Airflow Airflow
Downflow-Horizontal Furnace Vent Applications
Horizontal
Vertical
NOT APPROVED
NOT APPROVED
APPROVED
APPROVED
APPROVED
APPROVED
APPROVED

18-CD32D1-3 9
Installer’s Guide
7
50 CU. FT. OR MORE
PER 1000 BTU/HR. INPUT
ALL EQUIP. INSTALLED
UNCONFINED
8
CONFINED
LESS THAN 50 CU. FT.
PER 1000 BTU/HR. INPUT
ALL EQUIP INSTALLED
9
Typical Suspended Upflow/Horizontal Furnace
IMPORTANT:
Limited Warranty is conditional upon proper furnace and
vent system application and installation. Downflow fur-
naces installed in the vertical or horizontal position may
be vented through top or right side of the furnace cabinet
only (see figure 6 for defined top, left and right). A 90 de-
gree elbow may be installed inside the cabinet and rotated
so the vent pipe entering through the right side furnace
cabinet cutout can be connected to the elbow. Right side
venting may be used to provide access if an electronic
air cleaner is installed. Left side venting must use a 90
degree elbow outside the cabinet (Figure 6).
AIR FOR COMBUSTION AND VENTILATION
Adequate flow of combustion and ventilating air must not
be obstructed from reaching the furnace. Air openings
provided in the furnace casing must be free of obstructions
which restrict the flow of air. Airflow restrictions affect
the efficiency and safe operation of the furnace. Keep this
in mind should you choose to remodel or change the area
which contains your furnace. Furnaces must have a free
flow of air for proper performance.
Provisions for combustion and ventilation air shall be
made in accordance with “latest edition” of 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 Installation Codes, and applicable provisions of the
local building codes. Special conditions created by mechani-
cal exhausting of air and fireplaces must be considered to
avoid unsatisfactory furnace operation.
Furnace locations may be in “confined space” or “unconfined
space”. Unconfined space is defined in Table 2 and Figure
8. These spaces may have adequate air by infiltration to
provide air for combustion, ventilation, and dilution of
flue gases. Buildings with tight construction (for example,
weather stripping, heavily insulated, caulked, vapor bar-
rier, etc.), may need additional air provided as described for
confined space.
Confined spaces are installations with less than 50 cu. ft. of
space per 1000 BTU/hr input from all equipment installed.
Air for combustion and ventilation requirements can be
supplied from inside the building as in Figure 9 or from the
outdoors, as in Figure 10.
1. All air from inside the building as in Figure 9: The
confined space shall be provided with two permanent
openings connected directly to an additional room(s)
of sufficient volume so that the combined volume of all
spaces meets the criteria for an unconfined space. The
total input of all gas utilization equipment installed in
the combined space shall be considered in making this
determination. Refer to Table 3, for minimum open
areas required.
2. All air from outdoors as in Figure 11: The confined
space shall be provided with two permanent open-
ings, one commencing within 12 inches of the top and
one commencing within 12 inches of the bottom of the
enclosure.
The openings shall be connected directly, or by ducts,
with the outdoors or spaces (crawl or attic) that freely
connect to the outdoors. Refer to Table 3, for minimum
open areas required.
3. The following types of installations will require use
of OUTDOOR AIR for combustion, due to chemical
exposures:
* Commercial buildings
* Buildings with indoor pools
* Furnaces installed in commercial laundry rooms
* Furnaces installed in hobby or craft rooms
* Furnaces installed near chemical storage areas.
Exposure to the following substances in the combustion
air supply will also require OUTDOOR AIR for combus-
tion:
* Permanent wave solutions
* Chlorinated waxes and cleaners
* Chlorine based swimming pool chemicals
* Water softening chemicals
* Deicing salts or chemicals
* Carbon Tetrachloride
* Halogen type refrigerants
* Cleaning solvents (such as perchloroethylene)
* Printing inks, paint removers, varnish, etc.
* Hydrochloric acid
* Cements and glues
* Antistatic fabric softeners for clothes dryers
* Masonry acid washing materials

10 18-CD32D1-3
Installer’s Guide
q
0
TABLE 2
MINIMUM AREA IN SQUARE FEET
FOR UNCONFINED SPACE INSTALLATIONS
FURNACE
MAXIMUM BTUH
INPUT RATING
WITH 8 FT. CEILING
MINIMUM AREA IN SQUARE
FEET OF UNCONFINED SPACE
60,000
80,000
100,000
120,000
140,000
375
500
625
750
875
TABLE 3
MINIMUM FREE AREA IN SQUARE INCHES
EACH OPENING (FURNACE ONLY)
Furnace
Maximum
BTUH/INPUT
Rating
Air
From
Inside
Air From Outside
Vertical
Duct
Horizontal
Duct
60,000
80,000
100,000
120,000
140,000
100
100
100
120
140
15
20
25
30
35
30
40
50
60
70
DUCT CONNECTIONS
Air duct systems should be installed in accordance with
standards for air conditioning systems, National Fire Pro-
tection Association Pamphlet No. 90. They should be sized
in accordance with ACCA Manual D or whichever is appli-
cable. Check on controls to make certain they are correct
for the electrical supply.
Central furnaces, when used in connection with cooling
units, shall be installed in parallel or on the upstream side
of the cooling units to avoid condensation in the heating
element, unless the furnace has been specifically approved
for downstream installation. With a parallel flow arrange-
ment, the dampers or other means used to control flow of
air shall be adequate to prevent chilled air from entering
the furnace, and if manually operated, must be equipped
with means to prevent operation of either unit unless the
damper is in full heat or cool position.
On any job, flexible connections of nonflammable mate-
rial may be used for return air and discharge connections
to prevent transmission of vibration. Though these units
have been specifically designed for quiet, vibration free
operation, air ducts can act as sounding boards and could,
if poorly installed, amplify the slightest vibration to the
annoyance level.
When the furnace is located in a utility room adjacent to
the living area, the system should be carefully designed
with returns which minimize noise transmission through
the return air grille. Although these winter air condition-
ers are designed with large blowers operating at moderate
speeds, any blower moving a high volume of air will pro-
duce audible noise which could be objectionable when the
unit is located very close to a living area. It is often advis-
able to route the return air ducts under the floor or through
the attic. Such design permits the installation of air return
remote from the living area (i.e. central hall).
When the 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 and terminating outside
the space containing the furnace.
Minimum return air/“air entering” temperature for
the furnace is 55° F.
Where there is no complete return duct system, the return
connection must be run full size from the furnace to a
location outside the utility room, basement, attic, or crawl
space.
DO NOT install return air through the back of the
furnace cabinet.

18-CD32D1-3 11
Installer’s Guide
RETURN AIR DUCT CONNECTION
NOTE:
On upflow 5 ton airflow models, if the airflow requirement
exceeds 1800 CFM, these models will require return air
openings and filters on both sides; OR 1 side and the bot-
tom; OR just the bottom.
All return air duct systems should provide for installation
of return air filters.
PREPARATION FOR UPFLOW BOTTOM AND SIDE RE-
TURN AIR FILTER INSTALLATION
All return air duct systems should provide for installation
of return air filters.
1. Determine the appropriate position to set the furnace
in order to connect to existing supply and return duct-
work.
2. The return air filter is shipped in either the bottom or
side location. Remove the filter by first turning the
two latches on the blower door and tilting the door
forward to remove. Remove the filter by sliding it
out.
3. For upflow side return installations, remove the
insulation around the opening in the blower compart-
ment.
4. The side panels of the upflow furnace include locating
notches that are used as guides for cutting an open-
ing for return air, refer to Figure 13 and the outline
drawing on page 4 for duct connection dimensions for
various furnaces.
5. The bottom panel of the upflow furnace must be re-
moved for bottom return air. After removing the filter,
lay the furnace on its back. Remove the two 5/16" hex
screws securing the front of the bottom channel to
the cabinet. Rotate the channel downward (or remove
by lowering the front edge of the channel and pulling
forward). Slide the bottom return air panel out of the
cabinet. Rotate the front channel to its original posi-
tion and reinstall the two 5/16” screws.
6. If a 3/4" flange is to be used for attaching the air inlet
duct, add to cut where indicated by dotted lines in
Figure 13. Cut corners diagonally and bend outward to
form flange.
▲WARNING
!
TO PREVENT INJURY OR DEATH DUE TO CONTACT
WITH MOVING PARTS, TURN THE POWER TO THE
FURNACE OFF BEFORE SERVICING FILTERS.
7. If flanges are not required, and a filter frame is in-
stalled, cut between locating notches (See Figure 13).
8. Upflow Furnaces: filter clips are factory supplied for
bottom or side return. Use the filter clips on either side
or on the bottom if the filter is to be used within the
furnace cabinet.
When the upflow furnace is installed in the horizontal
right or left application and a return duct is attached
to the top side as shown in Figure 12, remove the filter
from the furnace and install in a remote location.
▲WARNING
!
Do not install the filter in the return duct directly above the
furnace in horizontal applications. Install the filter remotely.
Installing the filter directly above the furnace in horizontal
applications may cause property damage, serious injury or
death.
FILTER
REMOVE FILTER FROM UPFLOW
FURNACE WHEN RETURN DUCT IS
ATTACHED TO FURNACE TOP SIDE
(HORIZONTAL LEFT OR RIGHT AP-
PLICATIONS) AS SHOWN.
Close coupled (less than 36")
return (filter directly beneath bottom
side return) not recommended due to
noise considerations. If used, securely
attach 1/2" mesh metal hardware cloth
protective screen to the inside bottom
of filter grill.
Downflow Furnaces: Brackets are factory supplied
to mount filters in the return air duct work.
9. Connect the duct work to the furnace. See Outline
Drawing for supply and return duct size and location.
Flexible duct connectors are recommended to connect
both supply and return air ducts to the furnace.
If only the front of the furnace is accessible, it is recom-
mended that both supply and return air plenums are
removable.
10. When replacing a furnace, old duct work should be
cleaned out. Thin cloths should be placed over the
registers and the furnace fan should be run for 10 min-
utes. Don’t forget to remove the cloths before you start
the furnace.
w*SEE OUTLINE DRAWING
e
LOCATING
NOTCHES
PROVIDED
FOR SIDE
RETURN
CUTOUT
*
*
*
*CUT OUT
FOR
SIDE
FILTER
FRONT
of Furnace
When the upflow furnace is installed in the horizontal
right or left application and a close coupled (less than
36") return duct is attached to the bottom side of the
furnace as shown in Figure 12, securely attach a 1/2"
mesh metal hardware cloth protective screen to the
inside bottom of the filter grill to prevent personal
injury from contacting moving parts when reach-
ing into the return opening to replace the filter.
Close coupled (less than 36") return (filter directly
beneath bottom side return) is not recommended due to
noise considerations.

12 18-CD32D1-3
Installer’s Guide
TABLE 4
UPFLOW FURNACE RETURN AIR FILTERS
CABINET
WIDTH QTY* CABINET BOTTOM FILTER
CABINET
SIDE FILTER
17-1/2" 1 17" X 25" X 1" 17-1/2" X 25" X 1"
21" 1 20" X 25" X 1" 17-1/2" X 25" X 1"
24-1/2" 1 24" X 25" X 1" 17-1/2" X 25" X 1"
*First letter may be "A" or "T"
**NOTE: For upflow 5 ton airflow models where the airflow
requirement exceeds 1800 CFM - Models will require return air
openings and filters on: (1) both sides, or (2) one side and the
bottom, or (3) just on the bottom
BOTTOM FILTER RACK INSTALLATION
Airflow
11. The horizontal installation of the upflow furnace
requires an external filter section. Do NOT use the
bottom return filter within the furnace. Filter kits
are available for horizontal applications.
RETURN AIR FILTERS
TYPICAL UPFLOW RETURN AIR FILTER INSTALLATIONS
Filters are factory supplied for these furnaces. These
furnaces require high velocity type air filters. The filters
may be located within the furnace blower compartment for
UPFLOW furnaces in either a BOTTOM or SIDE (left side
or right side) return air inlet. Some filters may need to be
trimmed for side or bottom filter use.
NOTE: For upflow 5 ton airflow models where the airflow
requirement exceeds 1800 CFM - Models will require re-
turn air openings and filters on: (1) both sides, or (2) one
side and the bottom, or (3) just the bottom.
The furnace and the bottom filter rack, BAYRACK960,
installation can be seen in Figures 14 and 15.
Airflow
r
VIEW
ENGAGEMENT
HOLE DETAIL
(Typical both sides
and blower deck)
Blower Deck
Engagement
Hole
y
Filter Rack Assembly
t
ALTERNATE FILTER RACK INSTALLATION FOR BOTTOM
RETURN - BAYRACK960
The following checklist should be used when installing a
bottom return filter on an upflow furnace:
a. Remove the filter.
b. Remove the bottom panel.
c. With the filter removed, the filter rack is compressed
and then inserted into the bottom of the furnace. The
retaining screw/pin on each side inserts into engage-
ment holes at the bottom of the furnace cabinet side.
d. Reinstall the furnace filter in the bottom position
by inserting the chamfer end first into the filter rack.
See Figures 15-18.

18-CD32D1-3 13
Installer’s Guide
Cabinet Width Left Side Bottom Right Side
17.5 X X X
21 X X X
24.5 X X X
1. Remove bottom front channel to install or reposition filter rack.
X- All Models
ALTERNATE FILTER RACK INSTALLATION FOR SIDE
RETURN AIR ON UPFLOW FURNACES (LEFT OR RIGHT) -
BAYRACK960
The following checklist should be used when installing a
right or left side return filter in an upflow furnace:
a. Remove the filter.
b Leave the bottom panel in place.
c. Make side cutout by following the directions in the
“Return Air Duct Connections” section on page 9.
d. Compress the filter rack and reinstall in the side po-
sition on the furnace. Confirm that the upper retain-
ing pin/screw locks into the engagement hole in the
blower deck and the lower pin/screw rests against the
side of the bottom panel. See Figures 19-21.
e. Reinstall the furnace filter in the side position by
inserting the chamfer end first into the filter rack.
Filter
Rack
Furnace
Cabinet
Side
Filter Rack
Retaining
Screw/Pin
Engagement Hole
For
Bottom Return
Filter Rack
Installation With
u
RETAINING
PIN
(Both Sides)
SPRINGS
SIDE
CUTOUT
FILTER
RACK
RAILS
BOTTOM
PANEL
INSTALLED
Airflow
a
Typical Upflow Right Side Return Filter Rack Installation
RETAINING
PIN
(Both Sides)
SPRINGS
SIDE
CUTOUT
FILTER
RACK
RAILS
BOTTOM
PANEL
INSTALLED
Airflow
Typical Upflow Left Side Return Filter Rack Installation
p
Filter
Rack
Assembly
Furnace
Blower
Deck
Filter Rack
Retaining
Screw/Pin
Engagement Hole
For
Return
Filter Rack
Installation With
Side
Furnace
Cabinet
Side
BLOWER
DECK
o
BOTTOM ENGAGEMENT
Bottom Panel
Filter
Rack
Furnace
Cabinet
Side
Filter Rack
Retaining
Screw/Pin
Engagement Hole
For
Bottom Return
Filter Rack
Installation With
i

14 18-CD32D1-3
Installer’s Guide
RETURN AIR FILTERS FOR UPFLOW FURNACE
IN HORIZONTAL CONFIGURATION
When the Upflow Furnace is installed in the horizontal con-
figuration, the return air filters must be installed exterior
to the furnace cabinet. Remote filter grilles may be used for
homeowner convenience or the filters may be installed in
the duct work upstream of the furnace. See Figure 22.
d
UPFLOW FILTER CLIP / BRACKET INSTALLATION
1. Determine the location to be used. The furnace
cabinet has dimples for location of the furnace clips
(Side return only). Pre-drill clearance holes with a
3/16" drill. Bottom return holes are pre-drilled. Attach
clip to bottom channel and rear of unit with screws
provided for bottom return.
2. Install the clips in front and rear of the desired location
using the screws provided. The filter clip with the leaf
spring mounts in the rear of the cabinet. See Figure
23.
UNIT
SIZE
RETURN AIR
BOTTOM SIDE
17-1/2" DO NOT CUT DO NOT CUT
21" DO NOT CUT CUT ON LINE
24-1/2" DO NOT CUT CUT ON LINE
INSTALLING THE FILTER
The filter may need to be cut to fit the unit depending on
the location of the return air filter.
A score line and the words “CUT HERE” are located on the
end of the filter. If your application requires cutting the
filter, do so as indicted by the score mark.
Airflow
Airflow
f
TYPICAL DOWNFLOW FURNACE
RETURN AIR FILTER INSTALLATIONS
Two filters are factory supplied for each downflow furnace.
These furnaces require high velocity type air filters. Down-
flow furnace filters must be located outside the furnace
cabinet. Typical installations are shown in Figure 24.
Tables 5 and 6 provide information for installation of the
filter retaining brackets shipped with downflow furnaces.
Conversion kits for horizontal filters are BAYFLTR203
for 17 1/2" width cabinets, BAYFLTR204 for 21" width
cabinets, and BAYFLTR205 for 24" width cabinets. These
include filters and brackets necessary for horizontal filters.
In addition, optional door kit BAYFLTR206 is also avail-
able. See Figures 22 and 24.
Airflow
s
Typical Horizontal Filter Installation
Optional door kit
BAYFLTR206
Optional door kit
BAYFLTR206
SIDE
CUT-OUT
ALTERNATE SIDE
FILTER CLIPS
LOCATIONS
ALTERNATE BOTTOM
FILTER CLIPS LOCATIONS

18-CD32D1-3 15
Installer’s Guide
GENERAL VENTING INSTRUCTIONS
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 carbon monoxide
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. Seal any unused openings in the venting system.
2. Inspect the venting system for proper size and
horizontal pitch, as required in the National Fuel Gas
Code, ANSI Z223.1/NFPA 54 or the CAN/CGA B149
Installation Codes and these instructions. Determine
that there is no blockage or restriction, leakage,
corrosion and other deficiencies which could cause an
unsafe condition.
3. As far as practical, close all building doors and
windows and all doors between the space in which the
appliance(s) connected to the venting system are
located and other spaces of the building.
4. Close fireplace dampers.
5. Turn on clothes dryers and any appliance not
connected to the venting system. Turn on any exhaust
fans, such as range hoods and bathroom exhausts, so
they are operating at maximum speed. Do not operate
a summer exhaust fan.
6. Follow the lighting instructions. Place the appliance
being inspected into operation. Adjust the thermostat
so appliance is operating continuously.
7. If improper venting is observed during any of the above
tests, the venting system must be corrected in
accordance with the National Fuel Gas Code,
ANSI Z221.1/NFPA 54 and/or CAN/CGA B149
Installation Codes.
8. After it has been determined that each appliance
connected to the venting system properly vents where
tested as outlined above, return doors, windows,
exhaust fans, fireplace dampers and any other gas-fired
burning appliance to their previous conditions of use.
▲WARNING
!
TABLE 5
TABLE 6
CABINET
WIDTH
RETURN
DUCT
WIDTH
FILTER ACCESS
OPENING - DI-
MENSION "A"
FILTER ACCESS
OPENING -
DIMENSION "B"
17-1/2" 16-1/4" 15" 14"
21" 19-3/4" 19-1/2" 14"
24-1/2" 23-1/4" 22" 14"
CABINET
WIDTH
FILTER
SIZE
FILTER BRACKET
LOCATION *
17-1/2" 2 - 16X20X1 14-3/8"
21" 2 - 16X20X1 13-1/8"
24-1/2" 2 - 16X20X1 11-5/8"
* Location dimension is from end of duct to the screw holes for the bracket.
VENT PIPING
These furnaces have been classified as Fan-Assisted
Combustion System, Category I furnaces under the “lat-
est edition” provisions of ANSI Z21.47 and CAN/CGA 2.3
standards. Category I furnaces operate with a non-positive
vent static pressure and with a flue loss of not less than 17
percent.
NOTE:
If desired, a side wall termination can be accomplished
through the use of an “add-on” draft inducer. The inducer
must be installed according to the inducer manufacturer’s
instructions. Set the barometric pressure relief to achieve
-0.02 inch water column.
NOTE: When the downflow furnace is installed in the
horizontal right position with the right side of the fur-
nace cabinet facing down, the vent pipe must be routed
through the top panel of the furnace (See illustration 7 on
page 8). Do not install the vent pipe through the left side
of the cabinet.
The furnace shall be connected to a factory built chim-
ney or vent complying with a recognized standard, or a
masonry or concrete chimney lined with a lining material
acceptable to the authority having jurisdiction.
▲WARNING
!
CARBON MONOXIDE HAZARD
Furnace venting into an unlined masonry chimney or con-
crete chimney is prohibited. Failure to follow this warning
could result in property damage, personal injury, or death.
VENTING INTO A MASONRY CHIMNEY
If the chimney is oversized, the liner is inadequate, or
flue-gas condensation is a problem in your area, consider
using the chimney as a pathway or chase for type “B” vent
or flexible vent liner. If flexible liner material is used, size
the vent using the “B” vent tables, then reduce the maxi-
mum capacity by 20% (multiply 0.80 times the maximum
capacity). Masonry Chimney Kit BAYVENT800B may be
used with these furnaces (Upflow model furnaces only)
to allow venting into a masonry chimney. Refer to the BAY-
VENT800B Installer’s Guide for application requirements.
Internal Masonry Chimneys
Venting of fan assisted appliances into a lined, internal ma-
sonry chimney is allowed only if it is common vented with
at least one natural draft appliance; OR, if the chimney
is lined with type “B”, double wall vent or suitable flexible
liner material (See Table 7).
▲WARNING
!
CARBON MONOXIDE HAZARD
The chimney liner must be thoroughly inspected to insure
no cracks or other potential areas for flue gas leaks are
present in the liner. Liner leaks will result in early deterio-
ration of the chimney.
Failure to follow this warning could result in carbon mon-
oxide poisoning or death.

16 18-CD32D1-3
Installer’s Guide
TABLE 7
MASONRY CHIMNEY VENTING
Tile Lined Chimney Chimney Lining
Type Furnace Internal External “B” Vent
Flexible
Metal Liner
Single Fan
Assist No No Ye s Yes*
Fan Assist
+
Fan Assist No No Ye s Yes*
Fan Assist
+
Natural Ye s No Ye s Yes*
* Flexible chimney liner size is determined by using the type “B” vent size
for the available BTUH input, then reducing the maximum capacity by 20%
(multiply maximum capacity times 0.80). The minimum capacity is the same
as shown in the “B” vent tables.
EXTERNAL MASONRY CHIMNEY
Venting of fan assisted appliances into external chimneys
(one or more walls exposed to outdoor temperatures), re-
quires the chimney be lined with type “B”, double wall vent
or suitable flexible chimney liner material. This applies in
all combinations of common venting as well as for fan as-
sisted appliances vented alone.
The following installation practices are recommended to
minimize corrosion caused by condensation of flue products
in the furnace and flue gas system.
▲WARNING
!
CARBON MONOXIDE POISONING HAZARD
Failure to follow the installation instructions for the vent-
ing system being placed into operation could result in
carbon monoxide poisoning or death.
1. Avoid an excessive number of bends.
2. Horizontal runs should pitch upward at least 1/4" per
foot.
3. Horizontal runs should be as short as possible.
4. All vent pipe or connectors should be securely support-
ed and must be inserted into, but not beyond the inside
wall at the chimney vent.
5. When vent connections must pass through walls or
partitions of combustible material, a thimble must be
used and installed according to local codes.
6. Vent pipe through the roof should be extended to a
height determined by National Fuel Gas Code or local
codes. It should be capped properly to prevent rain
water from entering the vent. Roof exit should be wa-
terproofed.
7. Use type “B” double wall vent when vent pipe is routed
through cool spaces (below 60° F.).
8. Apply other good venting practices as stated in
the venting section of the National Fuel Gas Code
ANSI Z223.1 “latest edition”.
9. Vent connectors serving appliance vented by
natural draft or non-positive pressure shall not
be connected into any portion of a mechanized
draft system operating under positive pressure.
10. Horizontal pipe runs must be supported by hangers,
straps or other suitable material in intervals at a mini-
mum of every 3 feet of pipe.
11. A furnace shall not be connected to a chimney or flue
serving a separate appliance designed to burn solid
fuel.
12. The flow area of the largest section of vertical vent or
chimney shall not exceed 7 times the smallest listed ap-
pliance categorized vent area, flue collar area, or draft
hood outlet area unless designed in accordance with
approved engineering methods.
Maximum Vent or Tile
Lined Chimney Flow Area
*Drafthood outlet diameter, flue collar diameter, or listed appliance categorized vent
diameter.
▲WARNING
!
SAFETY HAZARD
The cabinet must have an uninterrupted or unbroken
ground according to National Electrical Code, ANSI/
NFPA 70 - “latest edition” and Canadian Electrical Code,
CSA C22.1 or local codes to minimize personal injury if an
electrical fault should occur. A failure to follow this warn-
ing could result in an electrical shock, fire, injury, or death.
▲CAUTION
!
The integrated furnace control is polarity sensitive. The
hot leg of the 115 VAC power must be connected to the
BLACK field lead.
▲WARNING
!
SHOCK HAZARD
To prevent injury or death due to electrical shock or con-
tact with moving parts, lock unit disconnect switch in the
open position before servicing the unit. Failure to follow
this warning could result in electrical shock, personal
injury, or death.
π(D*)2
4
= X 7
g
TABLE 8
NOTE:
The following section does not apply if BAYVENT800B
(Masonry Chimney Vent Kit) is used. All instructions with
the kit must be followed.
GAS VENT TERMINATION
ROOF PITCH MINIMUM HEIGHT
FLAT TO 7/12
OVER 7/12 TO 8/12
OVER 8/12 TO 9/12
OVER 9/12 TO 10/12 OVER 10/12
TO 11/12 OVER 11/12 TO 12/12
OVER 12/12 TO 14/12 OVER
14/12 TO 16/12
OVER 16/12 TO 18/12
OVER 18/12 TO 20/12 OVER
20/12 TO 22/12
1.0 FEET *
1.5 FEET
2.0 FEET
2.5 FEET
3.25 FEET
4.0 FEET
5.0 FEET
6.0 FEET
7.0 FEET
7.5 FEET
8.0 FEET
*THIS REQUIREMENT COVERS MOST INSTALLATIONS

18-CD32D1-3 17
Installer’s Guide
ELECTRICAL CONNECTIONS
▲CAUTION
!
Protect from Property Damage
Do NOT connect the furnace line voltage to a GFCI
protected circuit.
Failure to follow this warning could result in property
damage
NOTE:
The maximum total cable length for the entire Comfort
Control communicating system is 500 ft. 18 AWG. The
maximum distance of any single cable from a trans-
former is 250 ft. 18 AWG.
NOTE:
The BAYACCECOMM101 must be used when connect-
ing a *FD whole house air cleaner to a furnace in com-
municating mode. For 24 volt mode, see the installa-
tion in the whole house air cleaner installer's Guide.
NOTE:
The B/C terminal will requires three wires connected.
Rather than connecting the three wires to the low volt-
age terminal strip, create a pigtail using a short length
of thermostat wire and a wire nut (field supplied) to at-
tach to the B/C terminal.
NOTE: The BAYACCECOMM101 can be ordered
through the sales channels.
Make wiring connections to the unit as indicated on follow-
ing field wiring diagrams. As with all gas appliances using
electrical power, this furnace shall be connected into a per-
manently live electric circuit. It is recommended that it be
provided with a separate “circuit protection device” electric
circuit.
The furnace must be electrically grounded in accordance with
local codes or in the absence of local codes with the National
Electrical Code, ANSI/NFPA 70 “latest edition” or Canadian
Electrical Code, CSA C22.1, if an external electrical source is
utilized.
The hot leg of the 120V power supply must be connected to
the black power lead as indicated on the wiring diagram.
Provision for hooking up an Electronic Air Cleaner and/ or
Humidifier is provided on the Integrated Control. The fur-
nace control is polarity sensitive.
All field supplied wiring must conform with the temperature
limitation for Type T wire [63° F (35° C)], when installed
in accordance with these instructions and wiring diagrams
supplied with the furnace. A disconnecting means must
be located within sight from, and readily accessible to, the
furnace.
Refer to the SERVICE FACTS literature for unit wiring dia-
grams in addition to the diagram inside the blower door.
Communicating Indoor Unit with Communicating Comfort Control and Communicating Outdoor Unit

18 18-CD32D1-3
Installer’s Guide
Communicating Indoor Unit with Communicating Comfort Control and 24VAC Single Stage Cooling
24VAC Mode Indoor Unit with 24VAC Comfort Control and 24VAC Single Stage Cooling
NOTE:
To locate the BK to R jumper on the IFC board, see page 21.

18-CD32D1-3 19
Installer’s Guide
24VAC Mode Indoor Unit with 24VAC Comfort Control and 24VAC Single Stage Heat Pump
NOTE:
To locate the BK to R jumper on the IFC board, see page 21.
24VAC Mode Indoor Unit with 24VAC Comfort Control and 24VAC 2-Stage or 2-Step Cooling
NOTE:
To locate the BK to R jumper on the IFC board, see page 21.

20 18-CD32D1-3
Installer’s Guide
NOTE:
To locate the BK to R jumper on the IFC board, see page 21.
24VAC Mode Indoor Unit with 24VAC Comfort Control and 24VAC 2-Stage or 2-Step Heat Pump
Wiring Notes: