Lennox Allied Air Enterprises A95DF2V User manual

507052-04 Page 1 of 58Issue 1621
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) 507052-04
*P507052-04*
This manual must be left with the homeowner for future reference.
INSTALLATION INSTRUCTIONS
A95DF2V, 95G2DFV
Warm Air Gas Furnace / Downow Air Discharge
Direct Vent & Non-Direct Vent
TABLE OF CONTENTS
Unit Dimensions ................................................................ 2
Parts Arrangement............................................................. 3
Gas Furnace...................................................................... 4
Shipping and Packing List ................................................. 4
Safety Information ............................................................. 4
Use of Furnace as Construction Heater ............................ 5
General ............................................................................ 6
Combustion, Dilution & Ventilation Air ............................... 6
Setting Equipment ............................................................. 9
Filters .......................................................................... 12
Duct System .................................................................... 12
Pipe & Fittings Specications .......................................... 12
Joint Cementing Procedure............................................. 14
Venting Practices............................................................. 14
Vent Piping Guidelines .................................................... 16
Gas Piping....................................................................... 35
Electrical.......................................................................... 37
Control Diagnostics ......................................................... 42
Unit Start-Up.................................................................... 46
Gas Pressure Adjustment................................................ 47
High Altitude Information ................................................. 48
Other Unit Adjustments.................................................... 49
Blower Motor Performance.............................................. 50
Service .......................................................................... 52
Planned Service .............................................................. 54
Repair Parts List.............................................................. 55
Start-Up & Performance Check List ................................ 56

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Unit Dimensions - inches (mm)

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Figure 1
Expanded View

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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

507052-04 Page 5 of 58Issue 1621
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

507052-04Page 6 of 58 Issue 1621
• 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

507052-04 Page 7 of 58Issue 1621
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

507052-04Page 8 of 58 Issue 1621
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)

507052-04 Page 9 of 58Issue 1621
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)

507052-04Page 10 of 58 Issue 1621
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 downow 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.