Airease A95DF2E User manual

507206-01 Page 1 of 59Issue 1337
This is a safety alert symbol and should never be ignored. When you see this symbol on labels or in
manuals, be alert to the potential for personal injury or death.
As with any mechanical equipment, personal injury can
result from contact with sharp sheet metal edges. Be
careful when you handle this equipment.
CAUTION
Manufactured By
Allied Air Enterprises LLC
A Lennox International, Inc. Company
215 Metropolitan Drive
West Columbia, SC 29170
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal
injury or loss of life. Installation and service must
be performed by a licensed professional installer (or
equivalent), service agency or the gas supplier.
WARNING
(P) 507206-01
*P507206-01*
This manual must be left with the homeowner for future reference.
INSTALLATION INSTRUCTIONS
A95DF2E, 95G2DFE
Warm Air Gas Furnace / Downow Air Discharge
Direct Vent & Non-Direct Vent
Unit Dimensions .............................................................2
A95DF2E/95G2DFE Parts Arrangement........................3
A95DF2E/95G2DFE Gas Furnace .................................4
Shipping and Packing List ..............................................4
Safety Information .......................................................4
Use of Furnace as a Construction Heater ......................5
General .....................................................................6
Combustion, Dilution, Ventilation Air...............................6
Setting Equipment ..........................................................9
Filters ........................................................................12
Duct System .................................................................12
Pipe and Fittings Specications....................................12
Joint Cementing Procedure..........................................14
Venting Practices..........................................................14
TABLE OF CONTENTS
Vent Piping Guidelines .................................................16
Condensate Piping........................................................31
Gas Piping....................................................................35
Electrical.......................................................................37
Unit Start Up.................................................................48
Gas Pressure Adjustment.............................................49
High Altitude Information ..............................................50
Other Unit Adjustments.................................................51
Blower Motor Performance...........................................52
Service ........................................................................53
Planned Service ...........................................................55
Repair Parts List...........................................................56
Start Up Checklist.........................................................57
Commonwealth of Massachusetts.......................59

507206-01Page 2 of 59 Issue 1337
Unit Dimensions - inches (mm)
Model A B C
A95UH2E/95G2UHE in. mm in. mm in. mm
045-12 17-1/2 446 16-3/8 416 16 406
070-16
090-20 21 533 19-7/8 504 19-1/2 495
110-20

507206-01 Page 3 of 59Issue 1337
Figure 1

507206-01Page 4 of 59 Issue 1337
Gas Furnace
This Category IV gas furnace is shipped ready for installation
in the downow position.
The furnace is equipped for installation in natural gas
applications. A conversion kit (ordered separately) is
required for use in LP/propane gas applications.
This unit can be installed as either a Direct Vent or a
Non-Direct Vent gas central furnace.
NOTE: In Direct Vent installations, combustion air is taken
from outdoors and ue gases are discharged outdoors.
Non-Direct Vent installations, combustion air is taken from
indoors or ventilated attic or crawl space and ue gases are
discharged outdoors. See Figures 2A and 2B for application
involving roof termination.
Shipping and Packing List
Package 1 of 1 contains:
1 - Assembled Gas Unit
1 - Bag assembly containing the following:
1 - Snap bushing
1 - Snap Plug
1 - Wire tie
1 - Condensate trap
1 - Condensate trap cap
1 - Condensate trap clamp
1 - 2” diameter debris screen
1 - 3/4” Threaded street elbow
Check equipment for shipping damage. If you nd any
damage, immediately contact the last carrier.
Please refer to specication sheets for available accessories.
Safety Information
Use only the type of gas approved for use with this furnace.
Refer to unit nameplate.
This unit is CSA International certied to ANSI Z21.47 and
CSA 2.3 standards.
Building Codes
In the USA, installation of gas furnaces must conform with
local building codes. In the absence of local codes, units
must be installed according to the current National Fuel
Gas Code (ANSI Z223.1/NFPA 54). The National Fuel Gas
Code is available from the American National Standards
Institute, Inc., 11 West 42nd Street, New York, NY 10036.
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal
injury or loss of life. Installation and service must
be performed by a licensed professional installer (or
equivalent), service agency or the gas supplier.
WARNING
As with any mechanical equipment, personal injury can
result from contact with sharp sheet metal edges. Be
careful when you handle this equipment.
CAUTION
DANGER OF EXPLOSION!
DANGER
There are circumstances in which odorant used with
LP/propane gas can lose its scent. In case of a leak,
LP/propane gas will settle close to the oor and may be
difcult to smell. An LP/propane leak detector should
be installed in all LP applications.
Figure 2B
Figure 2A

507206-01 Page 5 of 59Issue 1337
In Canada, installation must conform with current National
Standard of Canada CSA-B149 Natural Gas and Propane
Installation Codes, local plumbing or waste water codes and
other applicable local codes.
In order to ensure proper unit operation in non-direct vent
applications, combustion and ventilation air supply must be
provided according to the current National Fuel Gas Code
or CSA-B149 standard.
Locations and Clearances
This furnace is CSA International certied for installation
clearances to combustible material as listed on the unit
nameplate and in the table in Figure 13. Accessibility
and service clearances must take precedence over re
protection clearances.
NOTE: When furnace is installed on a combustible oor,
a downow combustible ooring base must be installed
between the furnace and the oor.
For installation in a residential garage, the furnace must be
installed so that the burner(s) and the ignition source are
located no less than 18 inches (457 mm) above the oor.
The furnace must be located or protected to avoid physical
damage by vehicles. When a furnace is installed in a public
garage, hangar, or other building that has a hazardous
atmosphere, the furnace must be installed according to
recommended good practice requirements and current
National Fuel Gas Code or CSA B149 standards.
Note: Furnace must be adjusted to obtain a temperature
rise within the range specied on the unit nameplate. Failure
to do so may cause erratic limit operation and premature
heat exchanger failure.
This gas furnace must be installed so that its electrical
components are protected from water.
Installed in Combination with a Cooling Coil
When this furnace is used with cooling units (Figure 3),
it shall be installed in parallel with, or on the upstream
side of, cooling units to avoid condensation in the heating
compartment. With a parallel ow arrangement, a damper
(or other means to control the ow of air) must adequately
prevent chilled air from entering the furnace. If the damper is
manually operated, it must be equipped to prevent operation
of either the heating or the cooling unit, unless it is in the
full HEAT or COOL setting.
When installed, this furnace must be electrically grounded
according to local codes. In addition, in the United States,
installation must conform with the current National Electric
Code, ANSI/NFPA No. 70. The National Electric Code
(ANSI/NFPA No. 70) is available from the following address:
National Fire Protection Association
1 Battery March Park
Quincy, MA 02269
In Canada, all electrical wiring and grounding for the unit
must be installed according to the current regulations of
the Canadian Electrical Code Part I (CSA Standard C22.1)
and/or local codes.
NOTE: This furnace is designed for a minimum continuous
return air temperature of 60°F (16°C) or an intermittent
operation down to 55°F (13°C) dry bulb for cases where a
night setback thermostat is used. Return air temperature
must not exceed 85°F (29°C) dry bulb.
This gas furnace may be installed in alcoves, closets, attics,
basements, garages, and utility rooms.
This furnace design has NOT been CSA certified for
installation in mobile homes, recreational vehicles, or
outdoors.
Never use an open ame to test for gas leaks. Check all
connections using a commercially available soap solution
made specically for leak detection.
Use of Furnace as Construction Heater
These units are not recommended for use as a construction
heater during any phase of construction. Very low return air
temperature, harmful vapors and operation of the unit with
clogged or misplaced lters will damage the unit.
These units may be used for heating of buildings or
structures under construction, if the following conditions
are met:
•The vent system must be permanently installed per
these installation instructions.
•A room thermostat must control the furnace. The use
of xed jumpers that will provide continuous heating is
not allowed.
•The return air duct must be provided and sealed to the
furnace.
•Return air temperature range between 60°F (16°C) and
80°F (27°C) must be maintained.
• Air lters must be installed in the system and must be
maintained during construction.
Figure 3

507206-01Page 6 of 59 Issue 1337
• Air lters must be replaced upon construction completion.
•The input rate and temperature rise must be set per the
furnace rating plate.
•One hundred percent (100%) outdoor air must be provided
for combustion air requirements during construction.
Temporary ducting may supply outdoor air to the furnace.
Do not connect duct directly to the furnace. Size the
temporary duct following the instructions in section for
Combustion, Dilution and Ventilation Air in a conned
space with air from outside.
• The furnace heat exchanger, components, duct system,
air lters and evaporator coils must be thoroughly
cleaned following nal construction cleanup.
•All furnace operating conditions (including ignition, input
rate, temperature rise and venting) must be veried
according to these installation instructions.
General
These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
having jurisdiction before installation.
In addition to the requirements outlined previously, the
following general recommendations must be considered
when installing one of these furnaces:
•Place the furnace as close to the center of the air
distribution system as possible. The furnace should
also be located close to the vent termination point.
•When the furnace is installed in non-direct vent
applications, do not install the furnace where drafts
might blow directly into it. This could cause improper
combustion and unsafe operation.
•When the furnace is installed in a non-direct vent
applications, do not block the furnace combustion air
opening with clothing, boxes, doors, etc. Air is needed
for proper combustion and safe unit operation.
•When the furnace is installed in an attic or other
insulated space, keep insulation away from the furnace.
•When the furnace is installed in an unconditioned space,
consider provisions required to prevent freezing of the
condensate drain system.
NOTE: The Commonwealth of Massachusetts stipulates
these additional requirements:
•Gas furnaces shall be installed by a licensed plumber
or tter only.
•The gas cock must be “T handle” type.
•When a furnace is installed in an attic, the passageway
to and service area surrounding the equipment shall be
oored.
These units should not be installed in areas normally
subject to freezing temperatures.
CAUTION
Combustion, Dilution & Ventilation Air
If this unit is installed as a Non-Direct Vent Furnace,
follow the guidelines in this section.
NOTE: In Non-Direct Vent Installations, combustion air is
taken from indoors and ue gases are discharged outdoors.
Insufficient combustion air can cause headaches,
nausea, dizziness or asphyxiation. It will also cause
excess water in the heat exchanger resulting in rusting
and premature heat exchanger failure. Excessive
exposure to contaminated combustion air will result
in safety and performance related problems. Avoid
exposure to the following substances in the combustion
air supply:
Permanent wave solutions
Chlorinated waxes and cleaners
Chlorine base swimming pool chemicals
Water softening chemicals
De-icing salts or chemicals
Carbon tetrachloride
Halogen type refrigerants
Cleaning solvents (such as perchloroethylene)
Printing inks, paint removers, varnishes, etc.
Hydrochloric acid
Cements and glues
Antistatic fabric softeners for clothes dryers
Masonry acid washing materials
WARNING
In the past, there was no problem in bringing in sufcient
outdoor air for combustion. Inltration provided all the air
that was needed. In today’s homes, tight construction
practices make it necessary to bring in air from outside for
combustion. Take into account that exhaust fans, appliance
vents, chimneys, and replaces force additional air that
could be used for combustion out of the house. Unless
outside
The State of California has determined that this product
may contain or produce a chemical or chemicals, in
very low doses, which may cause serious illness or
death. It may also cause cancer, birth defects or other
reproductive harm.
WARNING

507206-01 Page 7 of 59Issue 1337
All gas-red appliances require air for the combustion
process. If sufcient combustion air is not available, the
furnace or other appliance will operate inefciently and
unsafely. Enough air must be provided to meet the needs of
all fuel-burning appliances and appliances such as exhaust
fans which force air out of the house. When replaces,
exhaust fans, or clothes dryers are used at the same time
as the furnace, much more air is required to ensure proper
combustion and to prevent a down draft. Insufcient air
causes incomplete combustion which can result in carbon
monoxide.
In addition to providing combustion air, fresh outdoor air
dilutes contaminants in the indoor air. These contaminants
may include bleaches, adhesives, detergents, solvents and
other contaminants which can corrode furnace components.
The requirements for providing air for combustion and
ventilation depend largely on whether the furnace is installed
in an unconned or a conned space.
Unconned Space
An unconned space is an area such as a basement or large
equipment room with a volume greater than 50 cubic feet
(1.42 m³) per 1,000 Btu (.29 kW) per hour of the combined
input rating of all appliances installed in that space. This
space also includes adjacent rooms which are not separated
by a door. Though an area may appear to be unconned,
it might be necessary to bring in outdoor air for combustion
if the structure does not provide enough air by
Do not install the furnace in a corrosive or contaminated
atmosphere. Meet all combustion and ventilation air
requirements, as well as all local codes.
CAUTION
air is brought into the house for combustion, negative
pressure (outside pressure is greater than inside pressure)
will build to the point that a down draft can occur in the
furnace vent pipe or chimney. As a result, combustion
gases enter the living space creating a potentially dangerous
situation.
In the absence of local codes concerning air for combustion
and ventilation, use the guidelines and procedures in this
section to install these furnaces to ensure efcient and safe
operation. You must consider combustion air needs and
requirements for exhaust vents and gas piping. A portion
of this information has been reprinted with permission from
the National Fuel Gas Code (ANSI-Z223.1/NFPA 54). This
reprinted material is not the complete and ofcial position
of ANSI on the referenced subject, which is represented
only by the standard in its entirely.
In Canada, refer to the CSA B149 Installation codes.
inltration. If the furnace is located in a building of tight
construction with weather stripping and caulking around
the windows and doors, follow the procedures in the “Air
from Outside” section.
Conned Space
A conned space is an area with a volume less than 50
cubic feet (1.42 m³) per 1,000 Btu (.29 kW) per hour of
the combined input rating of all appliances installed in that
space. This denition includes furnace closets or small
equipment rooms.
When the furnace is installed so that supply ducts carry
air circulated by the furnace to areas outside the space
containing the furnace, the return air must be handled by
ducts which are sealed to the furnace casing and which
terminate outside the space containing the furnace. This
is especially important when the furnace is mounted on
a platform in a conned space such as a closet or small
equipment room. Even a small leak around the base of the
unit at the platform or at the return air duct connection can
cause a potentially dangerous negative pressure condition.
Air for combustion and ventilation can be brought into the
conned space either from inside the building or from
outside.
Air from Inside
If the conned space that houses the furnace adjoins a
space categorized as unconned, air can be brought in by
providing two permanent openings between the two spaces.
Each opening must have a minimum free area of 1 square
inch (645 mm²) per 1,000 Btu (.29 kW) per hour of total
input rating of all gas-red equipment in the conned space.
Each opening must be at least 100 square inches (64516
mm²). One opening shall be within 12 inches (305 mm) of
the top of the enclosure and one opening within 12 inches
(305 mm) of the bottom. See Figure 4.
Figure 4
Equipment in Conned Space - All Air from Inside

507206-01Page 8 of 59 Issue 1337
Air from Outside
If air from outside is brought in for combustion and
ventilation, the conned space shall be provided with two
permanent openings. One opening shall be within 12” (305
mm) of the top of the enclosure and one within 12” (305
mm) of the bottom. These openings must communicate
directly or by ducts with the outdoors or spaces (crawl or
attic) that freely communicate with the outdoors or indirectly
through vertical ducts. Each opening shall have a minimum
free area of 1 square inch per 4,000 Btu (645 mm² per .59
kW) per hour of the total input rating of all equipment in the
enclosure (See Figures 5 and 6).
It is also permissible to bring air for combustion from a
ventilated attic (Figure 8) or ventilated crawl space (Figure
9).
When communicating with the outdoors through horizontal
ducts, each opening shall have a minimum free area of 1
square inch (645 mm²) per 2,000 Btu (.56 kW) per hour of
the total input rating of all equipment in the enclosure. See
Figure 7.
When ducts are used, they shall be of the same cross-
sectional area as the free area of the openings to which they
connect. The minimum dimension of rectangular air ducts
shall be no less than 3 inches (75 mm). In calculating free
area, the blocking effect of louvers, grilles, or screens must
be considered. If the design and free area of protective
covering is not known for calculating the size opening
required, it may be assumed that wood louvers will have 20
to 25 percent free area and metal louvers and grilles will
have 60 to 75 percent free area. Louvers and grilles must be
xed in the open position or interlocked with the equipment
so that they are opened automatically during equipment
operation.
Figure 5
Equipment in Conned Space - All Air from Outside
(Inlet Air from Crawl Space and Outlet Air to Ventilated Attic)
Figure 6
Equipment in Conned Space - All Air from Outside
(All Air Through Ventilated Attic)
Equipment in Conned Space - all Air from Outside
Figure 7
Figure 8
Equipment in Conned Space
(Inlet Air from Ventilated Attic & Outlet Air to Outside)

507206-01 Page 9 of 59Issue 1337
INSTALLATION – Setting Equipment
WARNING
Blower access panel must be securely in place when
blower and burners are operating. Gas fumes, which
could contain carbon monoxide, can be drawn into living
space resulting in personal injury or death.
WARNING
Do not install the furnace on its front, back or in the
horizontal position. See Figure 12. Do no connect the
return air ducts to the back of the furnace. Doing so
will adversely affect the operation of the safety control
devices, which could result in personal injury or death.
Select a location that allows for the required clearances that
are listed on the unit nameplate. Also consider gas supply
connections, electrical supply, vent connection, condensate
trap and drain connections, and installation and service
clearances [24 inches (610 mm) at unit front]. The unit must
be level from side to side. Tilt the unit slightly (maximum
1/2 in. from level) from back to front to aid in the draining of
the heat exchanger. See Figure 11.
Shipping Bolt Removal
NOTE: Units with a 1/2 hp blower motors are equipped with
three exible legs and one rigid leg. The rigid leg is equipped
with a shipping bolt and a at white plastic washer (rather
than the rubber mounting grommet used with a exible
mounting leg). See Figure 10. The bolt and washer must
be removed before the furnace is placed into operation.
After the bolt and washer have been removed, the rigid leg
will not touch the blower housing.
Allow for clearances to combustible materials as indicated
on the unit nameplate. Minimum clearances for closet or
alcove installations are shown in Figure 13.
Figure 11
Setting Equipment
Figure 10
Units with 1/2 HP Blower Motor
Figure 12
Figure 9
Equipment in Conned Space
(Inlet Air from Ventilated Crawlspace & Outlet Air to Outside)

507206-01Page 10 of 59 Issue 1337
Installation on Non-Combustible Flooring
1. Cut oor opening keeping in mind clearances listed
on unit rating plate. Also keep in mind gas supply
connections, electrical supply, flue and air intake
connections and sufcient installation and servicing
clearances. See Table 1 for correct oor opening size.
2. Flange warm air plenum and lower the plenum into the
opening.
3. Set the unit over the plenum and seal the plenum to the
unit.
4. Ensure that the seal is adequate.
Installation on Combustible Flooring
1. When unit is installed on a combustible oor, a downow
combustible ooring base must be installed between
the furnace and the oor. The base must be ordered
separately. See Table 2 for opening size to cut in oor.
The unit may be installed three ways in downflow
applications: on non-combustible ooring, on combustible
ooring using an additive base, or on a reverse-ow cooling
coil cabinet. Do not drag the unit across the oor in the
downow position. Floor and furnace ange damage
will result.
Refer to Figure 13 for clearances in downflow
applications.
Figure 13
Downow Application Installation Clearances
CAUTION
The furnace and combustible ooring base shall not be
installed directly on carpeting, tile, or other combustible
material other than wood ooring.
Table 1
Non-Combustible Floor Opening Size
Figure 14
WARNING
Improper installation of the furnace can result in
personal injury or death. Combustion and ue products
must never be allowed to enter the return air system
or air in the living space. Use sheet metal screws and
joint tape to seal return air system to furnace.
In platform installations with furnace return, the furnace
should be sealed airtight to the return air plenum. A
door must never be used as a portion of the return air
duct system. The base must provide a stable support
and an airtight seal to the furnace. Allow absolutely no
sagging, cracks, gaps, etc.
For no reason should return and supply air duct systems
ever be connected to or from other heating devices such
as a replace or stove, etc. Fire, explosion, carbon
monoxide poisoning, personal injury and/or property
damage could result.

507206-01 Page 11 of 59Issue 1337
2. After opening is cut, set the combustible ooring base
into opening.
3. Check berglass strips on the combustible ooring base
to make sure they are properly glued and positioned.
4. Lower supply air plenum into the combustible ooring
base until plenum anges seal against berglass strips.
er opening is
NOTE: Be careful not to damage berglass strips. Check
for a tight seal.
5. Set the furnace over the plenum.
6. Ensure that the seal between the furnace and plenum
is adequate.
Installation on Cooling Coil Cabinet
NOTE: Downow combustible ooring kit is not used.
1. Refer to reverse-ow coil installation instructions for
correctly sized opening in floor and installation of
cabinet.
2. When cooling cabinet is in place, set and secure the
furnace according to the instructions that are provided
with the cooling coil. Secure the furnace to the cabinet.
3. Seal the cabinet and check for air leaks.
Return Air Opening - Downow Units
Return air may be brought in only through the top opening of
a furnace installed in the downow position. The following
steps should be taken when installing plenum:
1. Bottom edge of plenum should be flanged with a
hemmed edge (See Figure 17 or 18).
2. Sealing strips should be used to ensure an airtight seal
between the cabinet and the plenum.
3. In all cases, plenum should be secured to top of furnace
using sheet metal screws.
4. Make certain that an adequate seal is made.
Figure 16
Figure 17
Figure 18
Combustible Flooring Base Opening Size
Table 2
Figure 15

507206-01Page 12 of 59 Issue 1337
Filters
This unit is not equipped with a lter or rack. A eld provided
lter is required for the unit to operate properly. Table 3 lists
recommended lter sizes.
A lter must be in place whenever the unit is operating.
CAUTION
Solvent cements for plastic pipe are ammable liquids
and should be kept away from all sources of ignition.
Do not use excessive amounts of solvent cement when
making joints. Good ventilation should be maintained to
reduce re hazard and to minimize breathing of solvent
vapors. Avoid contact of cement with skin and eyes.
Duct System
Use industry-approved standards to size and install the
supply and return air duct system. This will result in a quiet
and low-static system that has uniform air distribution.
NOTE: This furnace is not certied for operation in heating
mode (indoor blower operating at selected heating speed)
with an external static pressure which exceeds 0.8 inches
w.c. Operation at these conditions may result in improper
limit operation.
Supply Air Plenum
If the fumace is installed without a cooling coil, a removable
access panel should be installed in the supply air duct. The
access panel should be large enough to permit inspection
(by reected light) of the heat exchanger for leaks after the
furnace is installed. The furnace access panel must always
be in place when the furnace is operating and it must not
allow leaks into the supply air duct system.
Return Air Plenum
NOTE: Return air must not be drawn from a room where
this furnace, or any other gas-fueled appliance (i.e., water
heater), or carbon monoxide-producing device (i.e., wood
replace) is installed.
When return air is drawn from a room, a negative pressure
is created in the room. If a gas appliance is operating in a
room with negative pressure, the ue products can be pulled
back down the vent pipe and into the room. This reverse
ow of the ue gas may result in incomplete combustion
and the formation of carbon monoxide gas. This toxic
gas might then be distributed throughout the house by the
furnace duct system.
Use berglass sealing strips, caulking, or equivalent sealing
method between the plenum and the furnace cabinet to
ensure a tight seal. If a lter is installed, size the return air
duct to t the lter frame.
Pipe & Fittings Specications
All pipe, ttings, primer and solvent cement must conform
with American National Standard Institute and the American
Society for Testing and Materials (ANSI/ASTM) standards.
The solvent shall be free owing and contain no lumps,
undissolved particles or any foreign matter that adversely
affects the joint strength or chemical resistance of the
cement. The cement shall show no gelation, stratication,
or separation that cannot be removed by stirring. Refer
to Table 4 below for approved piping and tting materials.
Table 3
Table 4
Piping and Fittings Specications

507206-01 Page 13 of 59Issue 1337
The exhaust and intake connections are made of PVC.
Use PVC primer and solvent cement when using PVC
vent pipe. When using ABS vent pipe, use transitional
solvent cement to make connections to the PVC tting
in the unit.
IMPORTANT
Use PVC primer and solvent cement or ABS solvent cement
meeting ASTM specications, refer to Table 4. As an
alternate, use all purpose cement, to bond ABS, PVC, or
CPVC pipe when using ttings and pipe made of the same
materials. Use transition solvent cement when bonding ABS
to either PVC or CPVC.
Low temperature solvent cement is recommended during
cooler weather. Metal or plastic strapping may be used as
vent pipe hangers. Uniformly apply a liberal coat of PVC
primer for PVC or use a clean dry cloth for ABS to clean
inside socket surface of tting and male end of pipe to depth
of tting socket.
Canadian Applications Only
Pipe, ttings, primer and solvent cement used to vent
(exhaust) this appliance must be certied to ULC S636 and
supplied by a single manufacturer as part of an approved
vent (exhaust) system. When bonding the vent system to
the furnace, use ULC S636 approved One-Step Transition
Cement to bond the pipe to the ue collar. In addition, the
rst three feet of vent pipe from the furnace ue collar must
be accessible for inspection.
Table 5 lists the available exhaust termination kits. All vent
terminations are PVC.

507206-01Page 14 of 59 Issue 1337
Joint Cementing Procedure
All cementing of joints should be done according to the
specications outlined in ASTM D 2855.
NOTE: A sheet metal screw may be used to secure the
intake pipe to the connector, if desired. Use a drill or self
tapping screw to make a pilot hole.
1. Measure and cut vent pipe to desired length.
2. Debur and chamfer end of pipe, removing any ridges
or rough edges. If end is not chamfered, edge of pipe
may remove cement from tting socket and result in a
leaking joint.
3. Clean and dry surfaces to be joined.
4. Test t joint and mark depth of tting on outside of pipe.
5. Uniformly apply a liberal coat of PVC primer for PVC
or use a clean dry cloth for ABS to clean inside socket
surface of tting and male end of pipe to depth of tting
socket.
6. Promptly apply solvent cement to end of pipe and inside
socket surface of tting. Cement should be applied
lightly but uniformly to inside of socket. Take care to
keep excess cement out of socket. Apply second coat
to end of pipe.
NOTE: Time is critical at this stage. Do Not allow Primer
to dry before applying cement.
7. Immediately after applying last coat of cement to pipe,
and while both inside socket surface and end of pipe
are wet with cement, forcefully insert end of pipe into
socket until it bottoms out. Turn PVC pipe 1/4 turn
during assembly (but not after pipe is fully inserted) to
distribute cement evenly. Do not turn ABS or cellular
core pipe.
NOTE: Assembly should be completed within 20 seconds
after last application of cement. Hammer blows should not
be used when inserting pipe.
8. After assembly, wipe excess cement from pipe at end
of tting socket. A properly made joint will show a bead
around its entire perimeter. Any gaps may indicate an
improper defective assembly due to insufcient solvent.
9. Handle joints carefully until completely set.
DANGER OF EXPLOSION!
Fumes from PVC glue may ignite during system check.
Allow fumes to dissipate for at least 5 minutes before
placing unit into operation.
DANGER
Removal of the Furnace from Common Vent
In the event that an existing furnace is removed from a
venting system commonly run with separate gas appliances,
the venting system is likely to be too large to properly vent
the remaining attached appliances.
Conduct the following test while each appliance is operating
and the other appliances (which are not operating) remain
connected to the common venting system. If the venting
system has been installed improperly, you must correct the
system as indicated in the general venting requirements
section.
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.
WARNING
Venting Practices
Piping Suspension Guidelines
Figure 19

507206-01 Page 15 of 59Issue 1337
Figure 20
1. Seal any unused openings in the common venting
system.
2. Inspect the venting system for proper size and horizontal
pitch. Determine that there is no blockage, restriction,
leakage, corrosion, or other deciencies which could
cause an unsafe condition.
3. Close all building doors and windows and all doors
between the space in which the appliances remaining
connected to the common venting system are located
and other spaces of the building. Turn ON clothes
dryers and any appliances not connected to the common
venting system. Turn ON any exhaust fans, such as
range hoods and bathroom exhausts, so they will
operate at maximum speed. Do not operate a summer
exhaust fan. Close replace dampers.
4. Follow the lighting instructions. Turn ON the appliance
that is being inspected. Adjust the thermostat so that
the appliance operates continuously.
5. After the main burner has operated for 5 minutes, test
for leaks of ue gases at the draft hood relief opening.
Use the ame of a match or candle.
6. After determining that each appliance connected to
the common venting system is venting properly, (step
3) return all doors, windows, exhaust fans, replace
dampers, and any other gas burning appliances to their
previous mode of operation.
7. If a venting problem is found during any of the preceding
tests, the common venting system must be modied to
correct the problems.
Resize the common venting system to the minimum vent
pipe size determined by using the appropriate tables in
Appendix G. These are in the current standards of the
National Fuel Gas Code ANSI Z223.1.
1. In areas where piping penetrates joist or interior walls,
hole must be large enough to allow clearance on all
sides of pipe through center of hole using a hanger.
2. When furnace is installed in a residence where unit
is shut down for an extended period of time, such
as a vacation home, make provisions for draining
condensate collection trap and lines.
Exhaust Piping
Route piping to outside of structure. Continue with
installation following instructions given in piping termination
section.
Do not discharge exhaust into an existing stack or
stack that also serves another gas appliance. If vertical
discharge through an existing unused stack is required,
insert PVC pipe inside the stack until the end is even
with the top or outlet end of the metal stack.
CAUTION

507206-01Page 16 of 59 Issue 1337
Vent Piping Guidelines
This gas furnace can be installed as either a Non-Direct
Vent or a Direct Vent gas central furnace.
NOTE: In non-Direct Vent installations, combustion air is
taken from indoors and ue gases are discharged outdoors.
In Direct Vent installations, combustion air is taken from
outdoors and ue gases are discharged outdoors.
Intake and exhaust pipe sizing - Size pipe according
to Tables 6 and 7. Table 6 lists the minimum vent pipe
lengths permitted. Table 7A - 7C lists the maximum pipe
lengths permitted.
Regardless of the diameter of pipe used, the standard roof
and wall terminations described in section Exhaust Piping
Terminations should be used. Exhaust vent termination
pipe is sized to optimize the velocity of the exhaust gas as
it exits the termination.
Do not use screens or perforated metal in exhaust or
intake terminations. Doing so will cause freeze-ups and
may block the terminations.
IMPORTANT
In some applications which permit the use of several different
sizes of vent pipe, a combination vent pipe may be used.
Contact Allied Air Technical Service for assistance in sizing
vent pipe in these applications.
Table 6
The exhaust vent pipe operates under positive pressure
and must be completely sealed to prevent leakage of
combustion products into the living space.
CAUTION Use the following steps to correctly size vent pipe diameter.
Figure 21
MINIMUM VENT PIPE LENGTHS
A95DF2E/95G2DFE
MODELS
MIN.VENT LENGTH*
045,070,090,110 15 ft or 5 ft plus 2 elbows or
10 ft plus 1 elbow
*Any approved termination may be added to the minimm length listed.

507206-01 Page 17 of 59Issue 1337
A95DF2E & 95G2DFE
Table 7A

507206-01Page 18 of 59 Issue 1337
A95DF2E & 95G2DFE
Table 7B

507206-01 Page 19 of 59Issue 1337
A95DF2E & 95G2DFE
Table 7C

507206-01Page 20 of 59 Issue 1337
Typical Exhaust Pipe Connections
Figure 22
Figure 23
Typical Intake Pipe Connections (Direct Vent Applications)