ELITE® SERIIES GAS FURNACE
UP/FLOW HORIZONTAL AIR DISCHARGE
507264-03
06/2017
Superseds 03/2017
THIS MANUAL MUST BE LEFT WITH THE
HOMEOWNER FOR FUTURE REFERENCE
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.
WARNING
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 HVAC installer or
equivalent, service agency, or the gas supplier.
AIR FLOW
AIR FLOW
HORIZONTAL LEFT
UPFLOW
AIR FLOW
HORIZONTAL RIGHT
CAUTION
As with any mechanical equipment, personal injury can
result from contact with sharp sheet metal edges. Be
careful when you handle this equipment.
Table of Contents
Unit Dimensions - inches (mm) .....................................2
Shipping and Packing List ..............................................3
Safety Information ..........................................................3
Use of Furnace as Construction Heater .........................4
General ........................................................................... 5
EL296UH135XV60D24−1/2 in 622 mm23−3/8 in 594 mm23 in 584 mm11−1/8 in 283 mm
17−1/2 in 446 mm16−3/8 in 416 mm16 in 406 mm7−5/8 in 194 mm
21 in 533 mm19−7/8 in 505 mm19−1/2 in 495 mm9−3/8 in 238 mm
3/4
(19)
5/8
(16)
Page 2
3-1/4
(83)
23-1/2
(597)
1
Bottom Return
Air Opening
1-15/16 (49)
Page 3
EL296UHV Gas Furnace
NON-DIRECT VENT
INSTALLATION
NON-DIRECT VENT
INSTALLATION
COMBUSTION
AIR INTAKE INSIDE
VENTILATED
CRAWL SPACE
COMBUSTION
AIR INTAKE INSIDE
VENTILATED
ATTIC SPACE
EXHAUST
OUTLET
EXHAUST
OUTLET
The EL296UHV Category IV gas furnace is shipped ready
for installation in the upow or horizontal position. The furnace is shipped with the bottom panel in place. The bottom panel must be removed if the unit is to be installed
in horizontal or upow applications with bottom return air.
The EL296UHV can be installed as either a Direct Vent
or a Non-Direct Vent gas central furnace.
The furnace is equipped for installation in natural gas
applications. A conversion kit (ordered separately) is required for use in propane/LP gas applications.
NOTE - In Direct Vent installations, combustion air is tak-
en from outdoors and ue gases are discharged outdoors.
In Non-Direct Vent installations, combustion air is taken
from indoors or ventilated attic or crawlspace and ue
gases are discharged outdoors. See for applications involving roof termination.
DIRECT VENT INSTALLATIONNON-DIRECT VENT
EXHAUST OUTLET
COMBUSTION
AIR INTAKE OUTSIDE
OF HOUSE
INSTALLATION
EXHAUST
OUTLET
Shipping and Packing List
Package 1 of 1 contains
1 - Assembled EL296UHV unit
1 - Bag assembly containing the following:
Check equipment for shipping damage. If you nd any
damage, immediately contact the last carrier.
The following items may also be ordered separately:
1 - Thermostat
1 - LP/Propane changeover kit
1 - Return air base kit
1 - Horizontal suspension kit
1 - High altitude pressure switch
Safety Information
Figure 1
Figure 2
COMBUSTION
AIR INTAKE
INSIDE
OF HOUSE
CAUTION
As with any mechanical equipment, contact with sharp
sheet metal edges can result in personal injury. Take
care while handling this equipment and wear gloves and
protective clothing.
DANGER
Danger of explosion.
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
difcult to smell. An LP/propane leak detector should be
installed in all LP applications.
Use only the type of gas approved for use with this furnace. Refer to unit nameplate.
EL296UHV units are CSA International certied 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 following address:
American National Standards Institute, Inc.
11 West 42nd Street
New York, NY 10036
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.
Page 3
Page 4
In order to ensure proper unit operation in non-direct vent
Gas Unit
Heating Unit Installed Upstream of Cooling Unit
Gas Unit
Dampers
(open during heating operation only)
Dampers
(open during cooling operation only)
Heating Unit Installed Parallell to Air Handler Unit
Air Handler Unit
Evaporator
applications, combustion and ventilation air supply must
be provided according to the current National Fuel Gas
Code or CSA-B149 standard.
Installation Locations
This furnace is CSA International certied for installation
clearances to combustible material as listed on the unit
nameplate and in the table in Figure 12. Accessibility and
service clearances must take precedence over re protection clearances.
NOTE - For installation on combustible oors, the furnace
shall not be installed directly on carpeting, tile, or other
combustible material other than wood ooring.
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 specied on the unit nameplate. Failure to do so may cause erratic limit operation and premature heat exchanger failure.
This EL296UHV 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 coils (Figure 3), it shall be installed in
parallel with, or on the upstream side of, cooling coils 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 ai
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.
Figure 3
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.
The EL296UHV furnace may be installed in alcoves, closets, attics, basements, garages, crawl spaces and utility
rooms in the upow or horizontal position. This furnace
design has not been CSA certied for installation in mobile
homes, recreational vehicles, or outdoors.
Use of Furnace as Construction Heater
NOTE - Gas furnaces manufactured on or after May 1st
2017 are not permitted to be used in Canada for heating
of buildings or structures under construction.
The following statement only applies to the US. Lennox
does not recommend the use of EL296UHV units as a
construction heater during any phase of construction. Very
low return air temperatures, harmful vapors, construction
dust and operation of the unit with clogged or misplaced
lters may damage the unit.
However, EL296UHV units may be used for heating of
buildings or structures under construction in the US, if the
following conditions are met to ensure proper operation:
• 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.
Page 4
Page 5
• Air lters must be replaced upon construction com-
pletion.
• 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
these instructions in section for Combustion, Dilution and Ventilation Air in a conned space with air
from outside.
• The furnace heat exchanger, components, duct
system, air lters and evaporator coils must be
thoroughly cleaned following nal construction
clean-up.
• All furnace operating conditions (including ignition,
input rate, temperature rise and venting) must
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 fol-
lowing general recommendations must be considered
when installing a EL296UHV furnace:
• 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 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 condensate drain system.
• Please consult the manufacturer of your evaporator
coil for their recommendations on distance required
between the heat exchanger and their drain pan.
Adequate space must be provided between the
drain pan and the furnace heat exchanger.
CAUTION
EL296UHV unit should not be installed in areas normally
subject to freezing temperatures.
WARNING
This product contains a chemical known to the State
of California to cause cancer, birth defects, or other
reproductive harm.
WARNING
Insufcient 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
Combustion, Dilution & Ventilation Air
If the EL296UHV 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 or ventilated attic or crawlspace and
ue gases are discharged out-doors.
In the past, there was no problem in bringing in sufcient
outdoor air for combustion. Inltration 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, appli-
ance vents, chimneys, and replaces force additional air
that could be used for combustion out of the house.
Unless outside air is brought into the house for combus-
tion, negative pressure (outside pressure is greater than
inside pressure) will build to the point that a downdraft
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 EL296UHV furnaces to ensure ef-
Page 5
Page 6
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 com-
plete and ofcial position of the ANSI on the referenced
subject, which is represented only by the standard in its
entirety.
In Canada, refer to the CSA B149 installation codes.
CAUTION
Do not install the furnace in a corrosive or contaminated
atmosphere. Meet all combustion and ventilation air
requirements, as well as all local codes.
All gas-red appliances require air for the combustion
process. If sufcient combustion air is not available, the
furnace or other appliance will operate inefciently 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 downdraft. Insufcient 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 in-
stalled in an unconned or a conned space.
Unconned Space
An unconned 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
unconned, it might be necessary to bring in outdoor air
for combustion if the structure does not provide enough air
by inltration. 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
Conned Space
A conned 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 denition 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 conned space such as a closet or small
equipment room.
Even a small leak around the base of the unit at the plat-
form 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 conned space that houses the furnace adjoins a
space categorized as unconned, 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 conned
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.
EQUIPMENT IN CONFINED SPACE - ALL AIR FROM INSIDE
ROOF TERMINATED
EXHAUST PIPE
OPENINGS
SIDE WALL
TERMINATED
EXHAUST PIPE
(ALTERNATE
LOCATION)
NOTE - Each opening shall have a free area of at least one square inch
per 1,000 Btu (645mm
all equipment in the enclosure, but not less than 100 square inches
(64516mm.
2).
EL296UH
V
2
per .29kW) per hour of the total input rating of
(To Adjacent
Unconfined
Space)
Figure 4
Page 6
Page 7
Air from Outside
EQUIPMENT IN CONFINED SPACE - ALL AIR FROM OUTSIDE
hour of the total input rating of all equipment in the enclosure.
EQUIPMENT IN CONFINED SPACE
hour of the total input rating of all equipment in the enclosure.
EQUIPMENT IN CONFINED SPACE
If air from outside is brought in for combustion and ventilation, the conned space shall be provided with two permanent openings. One opening shall be within 12” (305mm)
of the top of the enclosure and one within 12” (305mm) 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 (645mm2 per 1.17kW)
per hour of total input rating of all equipment in the enclosure. When communicating with the outdoors through
horizontal ducts, each opening shall have a minimum free
area of 1 square inch per 2,000 Btu (645mm2 per .59kW)
per total input rating of all equipment in the enclosure (See
Figure 5). It is also permissible to bring in air for combus-
tion from a ventilated attic (gure 6) or ventilated crawl
space (Figure 7).
(Inlet Air from Crawl Space and Outlet Air to Outside)
(Inlet Air from Ventilated Crawlspace and Outlet Air to Outside)
Roof Terminated
Exhaust Pipe
Inlet Air
(Minimum
Ventilation
Louvers
(Crawl space)
Coupling or
3 in. to 2 in.
Transition
(Field Provided)
Furnace
12 in.(305mm)
Above crawl
space floor)
*Intake Debris Screen Provided)
VENTILATION LOUVERS
OUTLET
AIR
(Each end of attic)
2
per 1.17kW) per
ROOF TERMINATED
EXHAUST PIPE
SIDE WALL
TERMINATED
EXHAUST PIPE
(ALTERNATE
LOCATION)
NOTE-The inlet and outlet air openings shall each have a free area
of at least one square inch per 4,000 Btu (645mm
FURNACE
INLET
AIR
Figure 5
(Inlet Air from Ventilated Attic and Outlet Air to Outside)
Ventilation Louvers
Roof Terminated
Exhaust Pipe
*Intake Debris
Screen
(Provided)
Furnace
(Minimum
12 in.(305mm) Above
attic floor)
VENTILATION
LOUVERS
(For unheated
crawl space)
Inlet Air
NOTE-The inlet and outlet air openings shall each have a free area
of at least one square inch per 4,000 Btu (645mm
hour of the total input rating of all equipment in the enclosure.
2
per 1.17kW) per
Figure 7
If air from outside is brought in for combustion and ventilation, the conned space must have two permanent openings. 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. 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 (645 mm2) per 4,000
Btu (1.17 kW) per hour of total input rating of all equipment
in the enclosure. See Figure 5 and Figure 8. 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 total input rating of all equipment in the enclosure. See Figure 9.
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.
NOTE-The inlet and outlet air openings shall each have a free area
of at least one square inch per 4,000 Btu (645mm
Figure 6
2
per 1.17kW) per
Page 7
Page 8
EQUIPMENT IN CONFINED SPACE - ALL AIR FROM OUTSIDE
of the total input rating of all equipment in the enclosure.
ROOF TERMINATED
EQUIPMENT IN CONFINED SPACE - ALL AIR FROM OUTSIDE
of the total input rating of all equipment in the enclosure.
r
EXHAUST PIPE
(All Air Through Ventilated Attic)
VENTILATION LOUVERS
(Each end of attic)
OUTLET
AIR
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.
UNITS WITH 1/2 HP
BLOWER MOTOR
SIDE WALL
TERMINATED
EXHAUST PIPE
(ALTERNATE
LOCATION)
NOTE-The inlet and outlet air openings shall each have a free area of
at least one square inch per 4,000 Btu (645mm
FURNACE
INLET AIR
(Ends 12” above
bottom)
2
per 1.17kW) per hour
Figure 8
(All Air Through Ventilated Attic)
ROOF TERMINATED
EXHAUST PIPE
OUTLET
AIR
SIDE WALL
TERMINATED
EXHAUST PIPE
(ALTERNATE
LOCATION)
NOTE-The inlet and outlet air openings shall each have a free area of
at least one square inch per 4,000 Btu (645mm
FURNACE
VENTILATION LOUVERS
(Each end of attic)
INLET AIR
(Ends 12” above
bottom)
2
per 1.17kW) per hour
Figure 9
Shipping Bolt Removal
Units with 1/2 hp blower motor 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.
remove shipping bolt and washe
RIGID LEG
Figure 10
Installation - Setting Equipment
WARNING
Do not connect the return air duct 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.
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.
Upow Applications
The EL296UHV gas furnace can be installed as shipped
in the upow position. Refer to Figure 12 for clearances.
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. The unit may be
positioned from level to ½” toward the front. See Figure
11.
Allow for clearances to combustible materials as indicated
on the unit nameplate.
Page 8
Page 9
SETTING EQUIPMENT
END VIEW
Unit must be level side-to-side. Unit may be positioned from level to 1/2” toward the front to aid in draining.
UPFLOW APPLICATION
UNIT
FRONT
1/2” max.
SIDE VIEW
AIR FLOW
FRONT VIEW
UNIT
FRONT
SIDE VIEW
HORIZONTAL APPLICATION
AIR FLOW
FRONT VIEW
Figure 11
UNIT
FRONT
1/2”
max.
Page 9
Page 10
WARNING
Installation Clearances
Side Return Air
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.
Return Air Guidelines
Return air can be brought in through the bottom or either
side of the furnace installed in an upow application. If the
furnace is installed on a platform with bottom return, make
an airtight seal between the bottom of the furnace and the
platform to ensure that the furnace operates properly and
safely. The furnace is equipped with a removable bottom
panel to facilitate installation.
Markings are provided on both sides of the furnace cabinet for installations that require side return air. Cut the
furnace cabinet at the maximum dimensions shown on
page 2.
Refer to Engineering Handbook for additional information.
EL296UHV applications which include side return air
and a condensate trap installed on the same side of
the cabinet (trap can be installed remotely within 5
ft.) require either a return air base or eld-fabricated
transition to accommodate an optional IAQ accessory
taller than 14.5”. See Figure 13.
Top
Left SideRight Side
Bottom (Floor)
Top/Plenum1 in. (25 mm)
*Front0
Back0
Sides0†
Vent0
Floor0‡
*Front clearance in alcove installation must be 24 in. (610 mm).
Maintain a minimum of 24 in. (610 mm) for front service access.
†Allow proper clearances to accommodate condensate trap.
‡For installations on a combustible floor, do not install the furnace
directly on carpeting, tile or other combustible materials other
than wood flooring.
(with transition and filter)
20” X 25” X 1”
(508mmX635mmX 25mm)
Air Filter
Return
Air
Plenum
Transition
Figure 13
Figure 12
Page 10
Page 11
CONDENSATE
Removing the Bottom Panel
Bottom Panel
See figure 4.
TRAP
AIR FLOW
17−1/2 (446) B Width (50W98)
21 (533) C Width (50W99)
24−1/2 (622) D Width (51W00)
FURNACE
INDOOR AIR
QUALITY
CABINET
(PCO, Filter
Cabinet, etc.)
FRONT VIEW
NOTE- Optional side return air filter kits are not for use with return air base.
1
Both the unit return air opening and the base return air opening must be covered by a single plenum or IAQ cabinet.
Minimum unit side return air opening dimensions for units requiring 1800 cfm or more of air (W x H): 23 x 11 in. (584 x 279 mm).
The opening can be cut as needed to accommodate plenum or IAQ cabinet while maintaining dimensions shown.
Side return air openings must be cut in the field. There are cutting guides stenciled on the cabinet for the side return air
opening. The size of the opening must not extend beyond the markings on the furnace cabinet.
2
To minimize pressure drop, the largest opening height possible (up to 14 inches) is preferred.
Optional Return Air Base
(Upflow Applications Only)
FRONT
IF BASE
IS USED
WITHOUT
IAQ CABINET,
A SINGLE
RETURN AIR
PLENUM
MUST
COVER BOTH
UNIT AND
RETURN
AIR BASE
OPENINGS
OPTIONAL
RETURN
AIR BASE
3−1/4
(83)
7−1/4
(184)
1
23 (584)
Overall
(Maximum)
1
Unit side return air
Opening
SIDE RETURN
5−5/8
AIR OPENINGS
(143)
(Either Side)
26−7/8
(683)
SIDE VIEW
23
(584)
1
Minimum
11 (279)
2
Maximum
14 (356)
1
22−7/16
(570)
Overall
(Maximum)
3/4
(19)
Figure 14
Screw
Figure 15
Removing the Bottom Panel
Remove the two screws that secure the bottom cap to the
furnace. Pivot the bottom cap down to release the bottom
panel. Once the bottom panel has been removed, reinstall
the bottom cap. See Figure 15.
Horizontal Applications
WARNING
Do not install the furnace on its front or back.
See Figure 16.
Bottom Cap
FrontBack
Figure 16
Page 11
Page 12
The EL296UHV furnace can be installed in horizontal ap-
Horizontal Application
HORIZONTAL SUSPENSION KIT
plications with either right- or left-hand air discharge. Refer to Figure 17 for clearances in horizontal applications.
Installation Clearances
Metal Strap
(typical)
Internal Brace
(provided with kit)
Right-Hand Discharge
Air
Flow
dnE thgiRdnE tfeL
dnE thgiRdnE tfeL
AIR FLOW
Air
Flow
Bottom (Floor)**
Left-Hand Discharge
Top
AIR FLOW
Bottom (Floor)**
Top0
Front*0
Back0
Ends0
Vent0
Floor0‡
*Front clearance in alcove installation must be 24 in. (610 mm).
Maintain a minimum of 24 in. (610 mm) for front service access.
**An 8” service clearance must be maintained below the unit to
provide for servicing of the condensate trap.
‡For installations on a combustible floor, do not install the furnace
directly on carpeting, tile or other combustible materials other
than wood flooring.
Figure 17
Suspended Installation of Horizontal Unit
This furnace may be installed in either an attic or a crawlspace. Either suspend the furnace from roof rafters or
oor joists, as shown in Figure 18, or install the furnace
on a platform, as shown in Figure 19. A horizontal suspension kit (51W10) may be ordered from Lennox or use
equivalent.
NOTE - Heavy-gauge sheet metal straps may be used to
suspend the unit from roof rafters or ceiling joists. When
straps are used to suspend the unit in this way, support
must be provided for both the ends. The straps must not
interfere with the plenum or exhaust piping installation.
Cooling coils and supply and return air plenums must
be supported separately.
Bracket
(typical)
Air
Flow
Figure 18
NOTE - When the furnace is installed on a platform or with
the horizontal suspension kit in a crawlspace, it must be
elevated enough to avoid water damage, accommodate
drain trap and to allow the evaporator coil to drain.
Platform Installation of Horizontal Unit
1 - Select location for unit keeping in mind service and
other necessary clearances. See Figure 17.
2 - Construct a raised wooden frame and cover frame
with a plywood sheet. If unit is installed above
nished space, install an an auxiliary drain pan
under unit. Set unit in drain pan as shown in Figure
19. Leave 8 inches for service clearance below unit
for condensate trap.
3 - Provide a service platform in front of unit. When
installing the unit in a crawl space, a proper support
platform may be created using cement blocks.
4 - Route auxiliary drain line so that water draining from
this outlet will be easily noticed by the homeowner.
5 - If necessary, run the condensate line into a
condensate pump to meet drain line slope
requirements. The pump must be rated for use
with condensing furnaces. Protect the condensate
discharge line from the pump to the outside to avoid
freezing.
6 - Continue with exhaust, condensate and intake
piping installation according to instructions.
Page 12
Page 13
INTAKE PIPE
EXHAUST PIPE
*Gas connector may be
used for Canadian
able by local authority
having jurisdiction.
SERVICE PLATFORM
*GAS CONNECTION
RAISED
PLATFORM
Figure 19
Return Air -- Horizontal Applications
Return air may be brought in only through the end of a
furnace installed in the horizontal position. The furnace is
equipped with a removable bottom panel to facilitate installation. See Figure 15.
Filters
This unit is not equipped with a lter or rack. A eld-provided high velocity rated lter is required for the unit to
operate properly. Table 1 lists recommended lter sizes. A
lter must be in place whenever the unit is operating.
IMPORTANT
If a highefciency lter is being installed as part of this
system to ensure better indoor air quality, the lter must
be properly sized. Highefciency lters have a higher
static pressure drop than standardefciency glass/foam
lters. If the pressure drop is too great, system capacity
and performance may be reduced.
The pressure drop may also cause the limit to trip more
frequently during the winter and the indoor coil to freeze
in the summer, resulting in an increase in the number of
service calls.
Before using any lter with this system, check the
specications provided by the lter manufacturer against
the data given in the appropriate Lennox Product
Specications bulletin. Additional information is provided
in Service and Application Note ACC002
(August 2000).
TABLE 1
Furnace
Cabinet Width
Side ReturnBottom Return
17-1/2”16 X 25 X 1 (1)16 X 25 X 1 (1)
21”16 X 25 X 1 (1)20 X 25 X 1 (1)
24-1/2”16 X 25 X 1 (2)24 X 25 X 1 (1)
Filter Size
Duct System
Use industry-approved standards to size and install the
supply and return air duct system. Refer to ACCA Manual
D. This will result in a quiet and low-static system that has
uniform air distribution.
NOTE - This furnace is not certied 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 furnace 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 of the heat exchanger. The furnace access
panel must always be in place when the furnace is operating and it must not allow leaks.
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 de-
vice (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
raw gas or toxic fumes might then be distributed throughout the house by the furnace duct system.
Return air can be brought in through the bottom or either
side of the furnace (return air brought into either side of
furnace allowed only in upow applications). If a furnace
with bottom return air is installed on a platform, make an
airtight seal between the bottom of the furnace and the
platform to ensure that the unit operates properly and
safely. 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 Specications
All pipe, ttings, primer and solvent cement must conform
with American National Standard Institute and the American Society for Testing and Materials (ANSI/ASTM) stan-
dards. 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 the table 2 below for approved piping and tting
materials.
Page 13
Page 14
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.
TABLE 2
PIPING AND FITTINGS SPECIFICATIONS
Schedule 40 PVC (Pipe)D1785
Schedule 40 PVC (Cellular Core Pipe)F891
Schedule 40 PVC (Fittings)D2466
Schedule 40 CPVC (Pipe)F441
Schedule 40 CPVC (Fittings)F438
SDR-21 PVC or SDR-26 PVC (Pipe)D2241
SDR-21 CPVC or SDR-26 CPVC (Pipe)F442
Schedule 40 ABS Cellular Core DWV
(Pipe)
Schedule 40 ABS (Pipe)D1527
Schedule 40 ABS (Fittings)D2468
ABS-DWV (Drain Waste & Vent) (Pipe &
Fittings)
PVC-DWV (Drain Waste & Vent) Pipe &
Fittings)
PRIMER & SOLVENT CEMENT
PVC & CPVC PrimerF656
PVC Solvent CementD2564
CPVC Solvent CementF493
ABS Solvent CementD2235
PVC/CPVC/ABS All Purpose Cement
For Fittings & Pipe of the same material
ABS to PVC or CPVC Transition Solvent
Cement
CANADA PIPE & FITTING & SOLVENT
CEMENT
PVC & CPVC Pipe and Fittings
PVC & CPVC Solvent Cement
ABS to PVC or CPVC Transition
Cement
POLYPROPYLENE VENTING SYSTEM
PolyPro® by Duravent
InnoFlue® by Centrotherm
F628
D2661
D2665
ASTM
SPECIFICATION
D2564, D2235,
F493
D3188
MARKING
ULCS636
IMPORTANT
EL296UHV 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 ttings in the unit.
Use PVC primer and solvent cement or ABS solvent ce-
ment meeting ASTM specications, refer to Table 2. 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 for
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 certied to ULC S636 and supplied by a single manufacturer as part of an approved vent (exhaust) system. In
addition, the rst three feet of vent pipe from the furnace
ue collar must be accessible for inspection.
Page 14
Page 15
TABLE 3
OUTDOOR TERMINATION USAGE*
STANDARDCONCENTRIC
Wall Kit
2 inch3 inch2 inch
22G44
(US)
4
30G28
(CA)
44J40
(US)
4
81J20
(CA)
1
YES
1
YES
1
YES
1
YES
1
YES
1
YES
Input Size
045
070
090
Vent Pipe
Dia. in.
2
2-1/2
3
2
2-1/2
3
2
2-1/2
3
Flush
Mount Kit
51W11
(US)
51W12
(CA)
3
YESYES
3
YESYES
3
YESYES
3
YESYES
3
YESYES
3
YESYES
3
YESYESYES
3
YESYESYES
3
YESYESYES
2YESYESYES
110
2-1/2YESYES
3YESYES
1353YESYES
NOTE - Standard Terminations do not include any vent pipe or elbows external to the structure. Any vent pipe or elbows external to the structure must be included in total
vent length
calculations. See vent length tables.
* Kits must be properly installed according to kit instructions.
2Concentric kits 71M80 and 44W92 include 1-1/2” outdoor accelerator, when used with 045 and 070 input models.
3 Flush mount kits 51W11 and 51W12 includes 1-1/2 in. outdoor exhaust accelerator, required when used with 045, 070 and 090 input models.
4 Termination kits 30G28, 44W92, 44W93 and 81J20 are certied to ULC S636 for use in Canada only.
5 See table 8 for vent accelerator requirements.
Wall Ring
Kit
15F74
1
YES
1
YES
1
YES
1
YES
1
YES
1
YES
1-1.2 inch2 inch3 inch
Field
Fabricated
5
YES
5
YES
5
YES
5
YES
5
YES
5
YES
5
YESYESYES
5
YESYESYES
5
YESYESYES
5
YESYESYES
5
YESYESYES
5
YESYESYES
5
YESYES
71M80
(US)
4
44W92
(CA)
2
YES
2
YES
2
YES
2
YES
2
YES
2
YES
69M29
(US)
4
44W92
(CA)
60L46 (US)
4
44W93 (CA)
Joint Cementing Procedure
All cementing of joints should be done according to the
specications outlined in ASTM D 2855.
DANGER
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..
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.
NOTE - Check the inside of vent pipe thoroughly for
any obstruction that may alter furnace operation.
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.
NOTE - Time is critical at this stage. Do not allow
primer to dry before applying cement.
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.
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.
Page 15
Page 16
NOTE - Assembly should be completed within 20
Piping Suspension Guidelines
NOTE
r
roof in order to prevent transmission of vibration to the structure.
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 assembly due to insufcient
solvent.
9 - Handle joints carefully until completely set.
Venting Practices
SCHEDULE 40
PVC - 5'
all other pipe* - 3'
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.
WARNING
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:
* See Piping and Fittings Specifications table
- Isolate piping at the point where it exits the outside wall o
Wall Thickness Guidelines
24” maximum
3/4” minimum
Wall
Figure 20
1 - In areas where piping penetrates joists 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.
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.
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 deciencies
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
edistuoedisni
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, widows, 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 modied to correct the problem.
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
Page 16
Page 17
appliance.
REPLACING FURNACE THAT WAS PART OF A
COMMON VENT SYSTEM
Exhaust Pipe
CHIMNEY
OR GAS
VENT
(Check sizing
for water
heater only)
WATER
FURNACE
(Replaced)
If replacing a furnace which was
commonly vented with another gas appliance, the size
of the existing vent pipe for that gas appliance must be
checked. Without the heat of the original furnace flue
products, the existing vent pipe is probably oversized for
the single water heater or other appliance. The vent
should be checked for proper draw with the remaining
HEATER
OPENINGS
(To Adjacent
Room)
Figure 21
Exhaust Piping (Figure 22, Figure 24 and Figure 25)
Route piping to outside of structure. Continue with installation following instructions given in piping termination
section.
The EL296UHV 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 or ventilated attic or crawlspace 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 4 and 5. Count all elbows inside and outside the
home. Table 4 lists the minimum vent pipe lengths permitted. Table 5 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. Refer to table 8. In some applications which permit the use of several different sizes of
vent pipe, a combination vent pipe may be used. Contact
Lennox’ Application Department for assistance in sizing
vent pipe in these applications.
NOTE - The exhaust collar on all models is sized to accommodate 2” Schedule 40 vent pipe. In horizontal applications, any transition to exhaust pipe larger than 2”
must be made in vertical runs of the pipe. Therefore a 2”
elbow must be added before the pipe is transitioned to
any size larger than 2”. This elbow must be added to the
elbow count used to determine acceptable vent lengths.
Contact the Application Department for more information
concerning sizing of vent systems which include multiple
pipe sizes.
CAUTION
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.
The exhaust vent pipe operates under positive pressure
and must be completely sealed to prevent leakage of
combustion products into the living space.
Vent Piping Guidlines
NOTE - Lennox has approved the use of DuraVent® and
Centrotherm manufactured vent pipe and terminations
as an option to PVC. When using the PolyPro® by DuraVent or InnoFlue® by Centrotherm venting system the
vent pipe requirements stated in the unit installation instruction – minimum & maximum vent lengths, termination
clearances, etc. – apply and must be followed. Follow the
instructions provided with PoyPro by DuraVent and InnoFlue by Centrotherm venting system for assembly or if requirements are more restrictive. The PolyPro by Duravent
and InnoFlue by Centrotherm venting system must also
follow the uninsulated
CAUTION
Exhaust Pipe
Horizontal
Gas Furnace
NOTE -
ward unit. A minimum of 1/4” (6mm) drop for each 12” (305mm)
of horizontal run is mandatory for drainage.
NOTE - Exhaust pipe MUST be glued to furnace exhaust fittings.
NOTE - Exhaust piping should be checked carefully to make
sure there are no sags or low spots.
12” ma x
of straight pip
e
12”Min .
Figure 22
TABLE 4
MINIMUM VENT PIPE LENGTHS
EL296UHV MODELMIN. VENT LENGTH*
045, 070, 090, 110, 135
*Any approved termination may be added to the minimum length listed.
15 ft. or 5 ft plus 2 elbows or
10 ft plus 1 elbow
Page 17
Page 18
Piping Size Process
What is the
furnace capacity?
1
045, 070, 090,
110 or 135?
Which style termination
2
3
4
5
being used?
Standard or concentric?
See table 3.
Which needs
most elbows?
Intake or
exhaust?
How many elbows?
Count all elbows inside
and outside house.
Desired pipe size?
2”, 2-1/2”, 3”
IMPORTANT
Do not use screens or perforated metal in exhaust or
intake terminations. Doing so will cause freeze-ups and
may block the terminations.
What is the altitude of
6
the furnace installation?
Use table 5 or 6 to find
max intake or exhaust pipe
7
length. Includes all vent
pipe and elbows inside
and outside the house.
Figure 23
Page 18
Page 19
TABLE 5
Maximum Allowable Intake or Exhaust Vent Length in Feet
NOTE - Size intake and exhaust pipe length separately. Values in table are for Intake OR Exhaust, not combined total. Both Intake and Exhaust must
be same pipe size.
Standard Termination at Elevation 0 - 4500 ft
Number
Of 90°
Elbows
Used
045070090110135045070090110135045070090110135
181664422
2” Pipe2-1/2” Pipe3” Pipe
ModelModelModel
1151159358
138137118118114
2766139191101108853133132113113109
3715634141051058348128127108108104
4665129
100100784312312210310399
561462495957338118117989894
n/a
n/a
656411990906833113112939389
751361485856328108107888884
84631
94126757553189897787874
n/a
n/a
80805823103102838379
103621707048139392737369
Standard Termination Elevation 4500 - 10,000 ft
Number
Of 90°
Elbows
Usedl
04507009011 013504507009011 013504507009011 0135
1816644
2” Pipe2-1/2” Pipe3” Pipe
ModelModelModel
1151159358
13813711811811 4
2766139110110885313313211 3113109
37156341051058348128127108108104
4665129100100784312312210310399
561462495967338118117989894
n/an/a
n/a
656411990906833113112939389
751361485856328108107888884
84631
94126757553189897787874
n/a
103621707048139392737369
See concentric terminations next page.
80805823103102838379
Page 19
Page 20
TABLE 5 Continued
Maximum Allowable Intake or Exhaust Vent Length in Feet
NOTE - Size intake and exhaust pipe length separately. Values in table are for Intake OR Exhaust, not combined total.
Both Intake and Exhaust must be same pipe size.
Concentric Termination at Elevation 0 - 4500 ft
Number
Of 90°
Elbows
Used
045070090110135045070090110135045070090110135
173584222
2” Pipe2-1/2” Pipe3” Pipe
ModelModelModel
1051058954
121121114114105
2685337171001008449116116109109100
3634832129595794411111110410495
4584327
90907439106106999990
553382285856934101101949485
n/a
n/a
6483317808064299696898980
7432812757559249191848475
83823
93318656549148181747465
n/a
n/a
707054198686797970
102813606044n/a7676696960
Concentric Termination Elevation 4500 - 10,000 ft
Number
Of 90°
Elbows
Usedl
04507009011 013504507009011 013504507009011 0135
1735842
2” Pipe2-1/2” Pipe3” Pipe
ModelModelModel
1051058954
121121114114105
26853371001008449116116109109100
36348329595794411111110410495
458432790907439106106999990
553382285856934101101949485
n/an/a
n/a
6483317808064299696898980
7432812757559249191848475
83823
93318656549148181747465
n/a
102813606044n/a7676696960
707054198686797970
Page 20
Page 21
TABLE 6
Maximum Allowable Exhaust Vent Lengths With Furnace Installed in a Closet or Basement Using Ventilated
Attic or Crawl Space For Intake Air in Feet
NOTE - Size intake and exhaust pipe length separately. Values in table are for Intake OR Exhaust, not combined total.
Both Intake and Exhaust must be same pipe size.
NOTE - Additional vent pipe and elbows used to terminate the vent pipe outside the structure must be included in the
total vent length calculation
Standard Termination at Elevation 0 - 4500 ft
Number
Of 90°
Elbows
Used
045070090110135045070090110135045070090110135
171563414
2” Pipe2-1/2” Pipe3” Pipe
ModelModelModel
1001007843
118117989894
2665129995957338113112939389
3614624490906833108107888884
4564119
85856328103102838379
5513614808058239897787874
n/a
n/a
646319757553189392737369
741264707048138887686864
83621
9311660603837877585854
n/a
n/a
65654388382636359
102611555533n/a7372535349
Standard Termination Elevation 4500 - 10,000 ft
Number
Of 90°
Elbows
Usedl
04507009011 013504507009011 013504507009011 0135
1715634
2” Pipe2-1/2” Pipe3” Pipe
ModelModelModel
1001007843
118117989894
266512995957338113112939389
361462490906833108107888884
456411985856328103102838379
5513614808058239897787874
n/an/a
n/a
646319757553189392737369
741264707048138887686864
83621
9311660603837877585854
n/a
102611555533n/a7372535349
65654388382636359
Page 21
Page 22
TYPICAL EXHAUST AND INTAKE PIPE CONNECTIONS IN UPFLOW DIRECT OR
NON-DIRECT VENT APPLICATIONS
EXHAUST
2”
INTAKE
2”
EXHAUSTINTAKE
2”
2”
or
3”
TRANSITION
*2”
3”
TRANSITION
*2”
DO NOT transition
from smaller to larger
pipe in horizontal runs
of exhaust pipe.
* When transitioning up in pipe size, use the shortest length of 2” PVC pipe possible.
Figure 24
2”
2”
TYPICAL EXHAUST AND INTAKE PIPE CONNECTIONS IN HORIZONTAL DIRECT OR NON-DIRECT VENT
APPLICATIONS
12” max.
EXHAUST
2”
INTAKE
EXHAUST
*2”
INTAKE
* When transitioning up in pipe size, use the shortest length of 2” PVC pipe possible.
(RIGHT HAND DISCHARGE SHOWN)
2”
or
2”
2”
3”
*2”
2”
2”
TRANSITION
*2”
2”
or
2”
3”
*2”
45°
MAX
2”
*2”
2”
SIDE VIEW
DO NOT transition
from smaller to larger
pipe in horizontal runs
of exhaust pipe.
45°
MAX
Figure 25
Page 22
Page 23
Intake Piping
TYPICAL AIR INTAKE PIPE CONNECTIONS
(preferred) or with an elbow rotated to face down.
The EL296UHV furnace may be installed in either direct
vent or non-direct vent applications. In non-direct vent
applications, when intake air will be drawn into the furnace
from the surrounding space, the indoor air quality must be
considered and guidelines listed in Combustion, Dilution
and Ventilation Air section must be followed.
Follow the next two steps when installing the unit in Direct Vent applications, where combustion air is taken from
outdoors and ue gases are discharged outdoors. The
provided air intake screen must not be used in direct
vent applications (outdoors).
1 - Use transition solvent cement or a sheet metal screw
to secure the intake pipe to the inlet air connector.
2 - Route piping to outside of structure. Continue with
installation following instructions given in general
guidelines for piping terminations and intake and
exhaust piping terminations for direct vent sections.
Refer to table 5 for pipe sizes.
TYPICAL AIR INTAKE PIPE CONNECTIONS
UPFLOW NON−DIRECT
VENT APPLICATIONS
INTAKE
DEBRIS
SCREEN
(Provided)
NOTE - Debris screen and elbow may be rotated, so that
screen may be positioned to face forward or to either side.
Figure 26
HORIZONTAL NON−DIRECT VENT APPLICATIONS
(Horizontal Right−Hand Air Discharge Application Shown)
PVC pipe
coupling
OR
INTAKE
DEBRIS
SCREEN
(Provided)
NOTE - Debris screen may be positioned straight out
Figure 27
Follow the next two steps when installing the unit in NonDirect Vent applications where combustion air is taken
from indoors or ventilated attic or crawlspace and ue
gases are discharged outdoors.
1 - Use eld-provided materials and the factory-
provided air intake screen to route the intake piping
as shown in Figure 26 or Figure 27. Maintain a
minimum clearance of 3” (76mm) around the air
intake opening. The air intake opening (with the
protective screen) should always be directed
forward or to either side in the upow position, and
either straight out or downward in the horizontal
position.
The air intake piping must not terminate too close
to the ooring or a platform. Ensure that the intake
air inlet will not be obstructed by loose insulation
or other items that may clog the debris screen.
2 - If intake air is drawn from a ventilated attic (Figure
28) or ventilated crawlspace (Figure 29) the exhaust
vent length must not exceed those listed in table 6.
If 3” diameter pipe is used, reduce to 2” diameter
pipe at the termination point to accommodate the
debris screen.
3 - Use a sheet metal screw to secure the intake pipe
to the connector, if desired.
Page 23
Page 24
CAUTION
EQUIPMENT IN CONFINED SPACE
(Inlet Air from Ventilated Attic and Outlet Air to Outside)
NOTE-The inlet and outlet air openings shall each have a free area
of at least one square inch per 4,000 Btu (645mm
2
per 1.17kW) per
hour of the total input rating of all equipment in the enclosure.
Ventilation Louvers
Inlet Air
(Minimum
12 in.(305mm) Above
attic floor)
Roof Terminated
Exhaust Pipe
Furnace
*Intake Debris
Screen
(Provided)
EQUIPMENT IN CONFINED SPACE
If this unit is being installed in an application with
combustion air coming in from a space serviced by an
exhaust fan, power exhaust fan, or other device which
may create a negative pressure in the space, take care
when sizing the inlet air opening. The inlet air opening
must be sized to accommodate the maximum volume
of exhausted air as well as the maximum volume of
combustion air required forall gas appliances serviced
by this space.
Figure 28
(Inlet Air from Ventilated Crawlspace and Outlet Air to Outside)
Roof Terminated
Exhaust Pipe
Inlet Air
(Minimum
Ventilation
Louvers
(Crawl space)
(Field Provided)
NOTE-The inlet and outlet air openings shall each have a free area
of at least one square inch per 4,000 Btu (645mm
hour of the total input rating of all equipment in the enclosure.
Furnace
Coupling or
3 in. to 2 in.
Transition
12 in.(305mm)
Above crawl
space floor)
*Intake Debris Screen Provided)
2
per 1.17kW) per
General Guidelines for Vent Terminations
In Non-Direct Vent applications, combustion air is taken
from indoors or ventilated attic or crawlspace and the ue
gases are discharged to the outdoors. The EL296UHV is
then classied as a non-direct vent, Category IV gas furnace.
In Direct Vent applications, combustion air is taken from
outdoors and the ue gases are discharged to the outdoors. The EL296UHV is then classied as a direct vent,
Category IV gas furnace.
In both Non-Direct Vent and Direct Vent applications, the
vent termination is limited by local building codes. In the
absence of local codes, refer to the current National Fuel
Gas Code ANSI Z223-1/NFPA 54 in U.S.A., and current
CSA-B149 Natural Gas and Propane Installation Codes in
Canada for details.
Position termination according to location given in Figure
31 or Figure 32. In addition, position termination so it is
free from any obstructions and 12” above the average
snow accumulation.
At vent termination, care must be taken to maintain protective coatings over building materials (prolonged exposure
to exhaust condensate can destroy protective coatings).
It is recommended that the exhaust outlet not be located
within 6 feet (1.8m) of an outdoor AC unit because the
condensate can damage the painted coating.
NOTE - See table 7 for maximum allowed exhaust pipe
length without insulation in unconditioned space during
winter design temperatures below 32°F (0°C). If required
exhaust pipe should be insulated with 1/2” (13mm) Armaex or equivalent. In extreme cold climate areas, 3/4”
(19mm) Armaex or equivalent may be necessary. Insulation must be protected from deterioration. Armaex with
UV protection is permissable. Basements or other enclosed areas that are not exposed to the outdoor ambient
temperature and are above 32 degrees F (0°C) are to be
considered conditioned spaces.
IMPORTANT
Do not use screens or perforated metal in exhaust or
intake terminations. Doing so will cause freeze-ups and
may block the terminations.
IMPORTANT
For Canadian Installations Only:
In accordance to CSA International B149 installation
codes, the minimum allowed distance between the
combustion air intake inlet and the exhaust outlet of other
appliances shall not be less than 12 inches (305mm).
Figure 29
Page 24
Page 25
TABLE 7
Maximum Allowable Exhaust Vent Pipe Length (in ft.) Without Insulation In Unconditioned Space For
Winter Design Temperatures Two - Stage High Efciency Furnace
Winter Design
Temperatures1 °F
(°C)
32 to 21
(0 to -6)
Vent Pipe
Diameter
2 in2118333046423030n/an/a
2-1/2 in16n/a26n/a37n/a36n/an/an/a
045070090110135
PVC
2
PP
PVC
3 in12122121303029294242
20 to 1
(-7 to -17)
0 to -20
(-18 to -29)
1Refer to 99% Minimum Design Temperature table provided in the current edition of the ASHRAE Fundamentals Handbook.
2 Poly-Propylene vent pipe (PP) by Duravent and Centrotherm.
NOTE - Concentric terminations are the equivalent of 5’ and should be considered when measuring pipe length.
NOTE - Maximum unisulated vent lengths listed may include the termination(vent pipe exterior to the structure) and cannot exceed 5 linear feet or
the maximum allowable intake or exhaust vent length listed in table 5 or 6 which ever is less.
NOTE - If insulation is required in an unconditioned space, it must be located on the pipe closest to the furnace. See Figure 30.
2 in119191728252724n/an/a
2-1/2 in7n/a14n/a21n/a20n/an/an/a
3 inn/an/a99161614142323
2 in64121019161815n/an/a
2-1/2 inn/an/a7n/a13n/a12n/an/an/a
3 inn/an/an/an/a88771313
Unit Input Size
2
PP
PVC
2
PP
PVC
2
PP
PVC
2
PP
Conditioned
Space
Conditioned
Space
Figure 30
Pipe Insulation
Unconditioned
Space
Exhaust
Pipe
Intake
Pipe
Page 25
Page 26
VENT TERMINATION CLEARANCES
FOR NON-DIRECT VENT INSTALLATIONS IN THE US AND CANADA
K
D
E
L
B
C
F
G
A
B
J
A
M
I
H
INSIDE CORNER
DETAIL
VENT TERMINAL
AIR SUPPLY INLET
AREA WHERE TERMINAL
IS NOT PERMITTED
Fixed
Closed
Operable
B
Fixed
Closed
Operable
B
B
A =
B =
C =
D =
E =
F =
G =
H =
I =
J =
K =
L =
M =
US Installations
1
Canadian Installations
2
12 inches (305mm) or 12 in. (305mm)
above average snow accumulation.
12 inches (305mm) or 12 in. (305mm)
above average snow accumulation.
Clearance above grade, veranda,
porch, deck or balcony
Clearance to window or
door that may be opened
4 feet (1.2 m) below or to side of opening;
1 foot (30cm) above opening
6 inches (152mm) for appliances <10,000
Btuh (3kw), 12 inches (305mm) for
appliances > 10,000 Btuh (3kw) and
<100,000 Btuh (30kw), 36 inches (.9m)
for appliances > 100,000 Btuh (30kw)
Clearance to permanently
closed window
Vertical clearance to ventilated soffit
located above the terminal within a
horizontal distance of 2 feet (610 mm)
from the center line of the terminal
Clearance to unventilated soffit
Clearance to outside corner
Clearance to inside corner
tended above meter / regulator assembly
Clearance to service regulator
vent outlet
Clearance to non-mechanical air
pliance
ply inlet
Clearance above paved sidewalk or
paved driveway located on public property
Clearance under veranda, porch, deck or balcony
* 12”
* Equal to or greater than soffit depth.
*
* 3 feet (.9m)
* 12”
3 feet (.9m) within a height 15 feet (4.5m)
above the meter / regulator assembly
3 feet (.9m)
6 inches (152mm) for appliances <10,000
Btuh (3kw), 12 inches (305mm) for
appliances > 10,000 Btuh (3kw) and
<100,000 Btuh (30kw), 36 inches (.9m)
for appliances > 100,000 Btuh (30kw)
3 feet (.9m) above if within 10 feet
(3m) horizontally
6 feet (1.8m)
7 feet (2.1m)†
12 inches (305mm)‡
1
In accordance with the current ANSI Z223.1/NFPA 54 Natural Fuel Gas Code
2
In accordance with the current CSA B149.1, Natural Gas and Propane Installation Code
† A vent shall not terminate directly above a sidewalk or paved driveway that is
located between two single family dwellings and serves both dwellings.
‡ Permitted only if veranda, porch, deck or balcony is fully open
on a minimum of two sides beneath the floor. Lennox recommends
avoiding this location if possible.
4 feet (1.2 m) below or to side of opening;
1 foot (30 cm) above opening
7 feet (2.1m)†
* Equal to or greater than soffit depth.
* Equal to or greater than soffit depth.
* Equal to or greater than soffit depth.
* No minimum to outside corner* No minimum to outside corner
3 feet (.9m) within a height 15 feet (4.5m)
above the meter / regulator assembly
*12 inches (305mm)‡
**
*For clearances not specified in ANSI Z223.1/NFPA 54 or CSA
B149.1, clearance will be in accordance with local installation
codes and the requirements of the
lation instructions.”
Figure 31
Page 26
Page 27
VENT TERMINATION CLEARANCES
FOR DIRECT VENT INSTALLATIONS IN THE US AND CANADA
INSIDE CORNER
DETAIL
G
D
A
E
B
L
C
Fixed
F
Closed
Operable
B
Operable
B
B
VENT TERMINAL
AIR SUPPLY INLET
US Installations
A =
B =
Clearance above grade, veranda,
porch, deck or balcony
Clearance to window or
door that may be opened
12 inches (305mm) or 12 in. (305mm)
above average snow accumulation.
6 inches (152mm) for appliances <10,000
pliances > 10,000 Btuh (3kw) and <50,000
pliances > 50,000 Btuh (15kw)
C =
D =
E =
F =
G =
H =
I =
J =
K =
L =
M =
1
In accordance with the current ANSI Z223.1/NFPA 54 Natural Fuel Gas Code
2
In accordance with the current CSA B149.1, Natural Gas and Propane Installation Code
† A vent shall not terminate directly above a sidewalk or paved driveway that is located
between two single family dwellings and serves both dwellings.
‡ Permitted only if veranda, porch, deck or balcony is fully open on a minimum of
two sides beneath the floor. Lennox recommends avoiding this location if possible.
Clearance to permanently
closed window
Vertical clearance to ventilated soffit
located above the terminal within a
horizontal distance of 2 feet (610mm)
from the center line of the terminal
Clearance to unventilated soffit
Clearance to outside corner
Clearance to inside corner
tended above meter / regulator assembly
Clearance to service regulator
vent outlet
3 feet (.9m) within a height 15 feet (4.5m)
Clearance to non-mechanical air
pliance
ply inlet
Clearance above paved sidewalk or
paved driveway located on public property
Clearance under veranda, porch, deck or balcony
* Equal to or greater than soffit depth
* Equal to or greater than soffit depth* Equal to or greater than soffit depth
* No minimum to outside corner
above the meter / regulator assembly
6 inches (152mm) for appliances <10,000
pliances > 10,000 Btuh (3kw) and <50,000
pliances > 50,000 Btuh (15kw)
3 feet (.9m) above if within 10 feet
* 12”
*
*
3 feet (.9m)
(3m) horizontally
* 7 feet (2.1m)
*12 inches (305mm)‡
H
B
Fixed
Closed
A
J
AREA WHERE TERMINAL
IS NOT PERMITTED
1
12 inches (305mm) or 12 in. (305mm)
above average snow accumulation.
6 inches (152mm) for appliances <10,000
Btuh (3kw), 12 inches (305mm) for
appliances > 10,000 Btuh (3kw) and
<100,000 Btuh (30kw), 36 inches (.9m)
for appliances > 100,000 Btuh (30kw)
I
M
Canadian Installations
K
2
* 12”
* Equal to or greater than soffit depth* Equal to or greater than soffit depth
* No minimum to outside corner
*
3 feet (.9m) within a height 15 feet (4.5m)
above the meter / regulator assembly
3 feet (.9m)
6 inches (152mm) for appliances <10,000
Btuh (3kw), 12 inches (305mm) for
appliances > 10,000 Btuh (3kw) and
<100,000 Btuh (30kw), 36 inches (.9m)
for appliances > 100,000 Btuh (30kw)
6 feet (1.8m)
7 feet (2.1m)†
12 inches (305mm)‡
*For clearances not specified in ANSI Z223.1/NFPA 54 or CSA
B149.1, clearance will be in accordance with local installation
codes and the requirements of the gas supplier and these
installation instructions.”
Figure 32
Page 27
Page 28
Details of Intake and Exhaust Piping Terminations for
Exiting Exhaust and Intake Vent
Direct Vent Installations
NOTE - In Direct Vent installations, combustion air is taken
from outdoors and ue gases are discharged to outdoors.
NOTE - Flue gas may be slightly acidic and may adverse-
ly affect some building materials. If any vent termination
is used and the ue gasses may impinge on the building
material, a corrosion-resistant shield (minimum 24 inches
square) should be used to protect the wall surface. If the
optional tee is used, the protective shield is recommended. The shield should be constructed using wood, plastic,
sheet metal or other suitable material. All seams, joints,
cracks, etc. in the affected area should be sealed using an
appropriate sealant. See Figure 41.
Intake and exhaust pipes may be routed either horizontally through an outside wall or vertically through the roof. In
attic or closet installations, vertical termination through the
roof is preferred. Figure 33 through Figure 40 show typical
terminations.
1 - Intake and exhaust terminations are not required
to be in the same pressure zone. You may exit the
intake on one side of the structure and the exhaust
on another side (Figure 34). You may exit the
exhaust out the roof and the intake out the side of
the structure (Figure 35).
2 - Intake and exhaust pipes should be placed as close
together as possible at termination end (refer to
illustrations). Maximum separation is 3” (76MM)
on roof terminations and 6” (152MM) on side wall
terminations.
NOTE - When venting in different pressure zones,
the maximum separation requirement of intake and
exhaust pipe DOES NOT apply.
3 - On roof terminations, the intake piping should
terminate straight down using two 90° elbows (See
Figure 33).
4 - Exhaust piping must terminate straight out or up as
shown. A reducer may be required on the exhaust
piping at the point where it exits the structure to
improve the velocity of exhaust away from the
intake piping. See table 8.
NOTE - Care must be taken to avoid recirculation of
exhaust back into intake pipe.
5 - On eld-supplied terminations for side wall exit,
exhaust piping may extend a maximum of 12 inches
(305MM) for 2” PVC and 20 inches (508MM) for 3”
(76MM) PVC beyond the outside wall. Intake piping
should be as short as possible. See Figure 41.
6 - On eld-supplied terminations, a minimum distance
between the end of the exhaust pipe and the end of
the intake pipe without a termination elbow is 8” and
a minimum distance of 6” with a termination elbow.
See Figure 41.
7 - If intake and exhaust piping must be run up a
side wall to position above snow accumulation or
other obstructions, piping must be supported. At
least one bracket must be used within 6” from the
top of the elbow and then every 24” (610mm) as
shown in Figure 41, to prevent any movement in
any direction. When exhaust and intake piping
must be run up an outside wall, the exhaust piping
must be terminated with pipe sized per table 8.The
intake piping may be equipped with a 90° elbow
turndown. Using turndown will add 5 feet (1.5m) to
the equivalent length of the pipe.
Inches(mm)
8” (203mm) MIN
12” (305mm) ABOVE
AVERAGE SNOW
ACCUMULATION
3” (76mm) OR
2” (51mm) PVC
PROVIDE SUPPORT
FOR INTAKE AND
EXHAUST LINES
DIRECT VENT ROOF TERMINATION KIT
3”(76mm) MAX.
(15F75 or 44J41)
UNCONDITIONED
ATTIC SPACE
Figure 33
Exiting Exhaust and Intake Vent
(different pressure zone)
Exhaust
Pipe
Furnace
Inlet Air
(Minimum 12 in.
305 MM) above
grade or snow
accumulation
Figure 34
(different pressure zone)
Roof T
erminated
Exhaust Pipe
Inlet Air
Furnace
(Minimum 12 in.
305 MM) above
grade or snow
accumulation
Figure 35
Page 28
Page 29
TABLE 8
41W92 or 41W93 (Canada)
(30G28 or 81J20)
EXHAUST PIPE TERMINATION SIZE REDUCTION
EL296UHV
MODEL
*045 and 0701-1/2” (38MM)
*0902” (51MM)
1102” (51MM)
1352” (51MM)
*EL296UHV-045, -070 and -090 units with the ush mount termination
must use the 1-1/2”accelerator supplied with the kit.
Termination
Pipe Size
8 - A multiple furnace installation may use a group
of up to four terminations assembled together
horizontally, as shown in Figure 39.
FIELD-PROVIDED
QUIRED TO ADAPT
LARGER VENT PIPE
SIZE TO TERMINATION.
EXHAUST
AIR
INTAKE
AIR
OUTSIDE
WALL
CLAMP
(Not Furnished)
INTAKE
AIR
INTAKE
AIR
DIRECT VENT CONCENTRIC WALL TERMINATION
71M80, 69M29 or 60L46 (US)
EXHAUST
AIR
12” (305mm) Min.
above grade or
cumulation.
GRADE
2” EXTENSION FOR 2” PVC
PIPE1” EXTENSION FOR 3”
PVC PIPE
4''
FURNACE
INTAKE
PIPE
FLAT
SIDE
1-1/2” ACCELERATOR
FLUSH-MOUNT SIDE WALL TERMINATION KIT
51W11 (US) or 51W12 (Canada)
Figure 36
12” (305mm)
Minimum
Above Average
Snow
Accumulation
INTAKE
FURNACE
EXHAUST
PIPE
GLUE EXHAUST
END FLUSH INTO
TERMINATION
FLASHING
(Not Furnished)
Figure 38
EXHAUST
VENT
5”
(127mm)
INTAKE
AIR
18” MAX.
(457mm)
EXHAUST VENT
Inches (mm)
INTAKE
AIR
optional intake elbow
Side View
OPTIONAL VENT TERMINATION FOR MULTIPLE UNIT
INSTALLATION OF DIRECT VENT WALL TERMINATION KIT
12”
(305mm)
5-1/2”
(140mm)
Front View
12” (305mm) Min.
above grade or
cumulation.
Figure 39
DIRECT VENT APPLICATION
USING EXISTING CHIMNEY
STRAIGHT-CUT OR
ANGLE-CUT IN DIRECTION
OF ROOF SLOPE *
SHEET METAL STRAP
(Clamp and sheet metal strap
must be field−installed to support
CLAMP
the weight of the termination kit.)
FIELD-PROVIDED
REDUCER MAY BE REQUIRED
TO ADAPT LARGER VENT
PIPE SIZE TO TERMINATION
DIRECT VENT CONCENTRIC ROOFTOP TERMINATION
71M80, 69M29 or 60L46 (US)
44W92 or 44W93 (Canada)
Figure 37
Page 29
3” - 8”
8” - 12”
(203mm - 305mm)
Minimum 12” (305MM)
above chimney top
plate or average snow
accumulation
*SIZE TERMINATION
PIPE PER TABLE 7.
NOTE - Do
tical discharge through an existing unused chimney or stack is required, insert piping
inside
trated. In any exterior portion of chimney, the exhaust vent must be insulated.
INTAKE PIPE
INSULATION (optional)
SHEET
METAL TOP
PLATE
INSULATE
TO FORM
SEAL
(76mm-
203mm)
SHOULDER OF FITTINGS
PROVIDE SUPPORT
OF PIPE ON TOP PLATE
3” - 8”
(76mm-
203mm)
ALTERNATE
INTAKE PIPE
EXTERIOR
PORTION OF
CHIMNEY
Figure 40
Page 30
NOTE − FIELD−PROVIDED
REQUIRED TO ADAPT
LARGER VENT PIPE SIZE
* WALL
SUPPORT
C1
B
2
B
2
FIELD FABRICATED WALL TERMINATION
REDUCER MAY BE
TO TERMINATION
C1
A
E
D
B
STRAIGHT
APPPLICATION
A
Intake
Elbow
D
B
EXTENDED
APPLICATION
C2
C2
D
B
A
E
D
B
A
A− Minimum clearance
above grade or average
snow accumulation
B− Maximum horizontal
separation between
intake and exhaust
C1 -Minimum from end of
exhaust to inlet of intake
C2 -Minimum from end of
exhaust to inlet of intake
D− Maximum exhaust
pipe length
E− Maximum wall support
distance from top of each
pipe (intake/exhaust)
See maximum allowable venting tables for venting
lengths with this arrangement.
* Use wall support every 24” (610 mm). Use two
wall supports if extension is greater than
24” (610 mm) but less than 48” (1219 mm).
NOTE − One wall support must be within 6” (152 mm)
from top of each pipe (intake and exhaust) to prevent
movement in any direction.
The exhaust termination tee should be connected to the 2” or 3” PVC flue pipe as shown in the illustration. In
horizontal tee applications there must be be a minimum of 3 ft away from covered patios or any living ares and
cannot be within 3 ft of a window. Do not use an accelerator in applications that include an exhaust termination
tee. The accelerator is not required.
2
As required. Flue gas may be acidic and may adversely affect some building materials. If a side wall vent
termination is used and flue gases will impinge on the building materials, a corrosion−resistant shield
(24 inches square) should be used to protect the wall surface. If optional tee is used, the protective shield
is recommended. The shield should be constructed using wood, sheet metal or other suitable material.
All seams, joints, cracks, etc. in affected area, should be sealed using an appropriate sealant.
3
Exhaust pipe 45° elbow can be rotated to the side away from the combustion air inlet to direct exhaust
away from adjacent property. The exhaust must never be directed toward the combustion air inlet.
Intake
Elbow
1
C
A
E
B
2
A
3
D
1
12”
C
A− Clearance above
grade or average snow
accumulation
B− Horizontal
separation between
intake and exhaust
C− Minimum from
end of exhaust to
inlet of intake
D− Exhaust pipe length
E− Wall support distance
from top of each pipe
(intake/exhaust)
Front View of
Intake and Exhaust
Intake
Exhaust
Figure 41
2” (51mm)
Vent Pipe
12” (305 mm)
12” (305 mm)
6” (152 mm)
2” (51MM)
Vent Pipe
12” (305 mm) Min.12” (305 mm) Min.
6” (152 mm) Min.
24” (610 mm) Max.
9” (227 mm) Min.
12” (305 mm) Min.
16” (405 mm) Max.
6” (152 mm) Max.
3” (76mm)
Vent Pipe
12” (305 mm)
6” (152 mm)6” (152 mm)
8” (203 mm)8” (203 mm)
6” (152 mm)6” (152 mm)
20” (508 mm)
6” (152 mm)
3” (76MM)
Vent Pipe
6” (152 mm) Min.
24” (610 mm) Max.
9” (227 mm) Min.
12” (305 mm) Min.
20” (508 mm) Max.
6” (152 mm) Max.
Page 30
Page 31
Details of Exhaust Piping Terminations for Non-Direct
Vent Applications
Exhaust pipes may be routed either horizontally through
an outside wall or vertically through the roof. In attic or
closet installations, vertical termination through the roof
is preferred. Figure 42 and Figure 43 show typical terminations.
1 - Exhaust piping must terminate straight out or up as
shown. The termination pipe must be sized as listed
in table 8.The specied pipe size ensures proper
velocity required to move the exhaust gases away
from the building.
2 - On eld supplied terminations for side wall exit,
exhaust piping may extend a maximum of 12 inches
(305MM) for 2” PVC and 20 inches (508MM) for 3”
(76MM) PVC beyond the outside wall.
DIRECT VENT APPLICATION
USING EXISTING CHIMNEY
3” - 8”
(203mm - 305mm)
Minimum 12” (305MM)
above chimney top
plate or average snow
accumulation
*SIZE TERMINATION
PIPE PER TABLE 7.
8” - 12”
INSULATION (optional)
INSULATE
TO FORM
SEAL
INTAKE PIPE
SHEET
METAL TOP
PLATE
(76mm203mm)
STRAIGHT-CUT OR
ANGLE-CUT IN DIRECTION
OF ROOF SLOPE *
SHOULDER OF FITTINGS
PROVIDE SUPPORT
OF PIPE ON TOP PLATE
3” - 8”
(76mm203mm)
ALTERNATE
INTAKE PIPE
EXTERIOR
PORTION OF
CHIMNEY
12” (305mm)
ABOVE AVE.
SNOW
ACCUMULATION
3” (76mm) OR
2” (51mm) PVC
PROVIDE SUPPORT
FOR EXHAUST LINES
UNCONDITIONED
ATTIC SPACE
NON-DIRECT VENT ROOF TERMINATION KIT
(15F75 or 44J41)
Figure 42
3 - If exhaust piping must be run up a side wall
to position above snow accumulation or other
obstructions, piping must be supported every 24
inches (610MM). When exhaust piping must be run
up an outside wall, any reduction in exhaust pipe
size must be done after the nal elbow.
4 - Distance between exhaust pipe terminations on
multiple furnaces must meet local codes.
Crawl Space and Extended Horizontal Venting
NOTE - Do
tical discharge through an existing unused chimney or stack is required, insert piping
inside
trated. In any exterior portion of chimney, the exhaust vent must be insulated.
Figure 43
Venting In A Crawl Space
Basement Floor
Lennox provides kit 51W18 (USA) and kit 15Z70 (Cana-
da) to install 2” or 3” PVC exhaust piping through the oor
joists and into the the crawl space. See Figure 44.
This kit can also be used as a supplemental drain for in-
stallations with condensate run back in the vent pipe (ie.
long horizontal runs, unconditioned spaces, etc.).
KIT 51W18
(USA)
KIT 15Z70
(CANADA)
Figure 44
Page 31
Page 32
Condensate Piping
This unit is designed for either right- or left-side exit of
condensate piping in upow applications. In horizontal
applications, the condensate trap must extend below the
unit. An 8” service clearance is required for the condensate trap. Refer to Figure 45 and Figure 47 for condensate
trap locations. Figure 53 shows trap assembly using 1/2”
PVC or 3/4” PVC.
NOTE - If necessary the condensate trap may be installed
up to 5’ away from the furnace. Use PVC pipe to connect
trap to furnace condensate outlet. Piping from furnace
must slope down a minimum of 1/4” per ft. toward trap.
1 - Determine which side condensate piping will exit
the unit, location of trap, eld-provided ttings and
length of PVC pipe required to reach available
drain.
2 - Use a large at head screw driver or a 1/2” drive
socket extension and remove plug (Figure 45) from
the cold end header box at the appropriate location
on the side of the unit. Install provided 3/4 NPT
street elbow tting into cold end header box. Use
Teon tape or appropriate pipe dope.
NOTE - Cold end header box drain plugs are factory installed. Check the unused plug for tightness to
prevent leakage.
3 - Install the cap over the clean out opening at the
base of the trap. Secure with clamp. See Figure 53.
4 - Install drain trap using appropriate PVC ttings,
glue all joints. Glue the provided drain trap as
shown in Figure 53. Route the condensate line to
an open drain. Condensate line must maintain a
1/4” downward slope from the furnace to the drain.
5 - Figure 48 and Figure 49 show the furnace and
evaporator coil using a separate drain. If necessary
the condensate line from the furnace and evaporator
coil can drain together. See Figure 50, Figure 51 and
Figure 52. Upow furnace (Figure 51) - In upow
furnace applications the eld provided vent must
be a minimum 1” to a maximum 2” length above
the condensate drain outlet connection. Any length
above 2” may result in a ooded heat exchanger
if the combined primary drain line were to become
restricted. Horizontal furnace (Figure 52) - In
horizontal furnace applications the eld provided
vent must be a minimum 4” to a maximum 5” length
above the condensate drain outlet connection.
Any length above 5” may result in a ooded heat
exchanger if the combined primary drain line were
to become restricted.
CONDENSATE TRAP AND PLUG LOCATIONS
(Unit shown in upflow position)
Trap
(same on
right side)
1-1/2 in.
NOTE - In upflow applications where side return
sate trap, filter rack must be installed beyond
condensate trap or trap must be re-located to
avoid interference.
Figure 45
NOTE - In horizontal applications it is recommended to
install a secondary drain pan underneath the unit and trap
assembly.
NOTE - Appropriately sized tubing and barbed tting may
be used for condensate drain. Attach to the drain on the
trap using a hose clamp. See Figure 46.
Field Provided Drain Components
Elbow
Tubing
Hose Clamp
Figure 46
Rubber
Grommet
Plug
(same on left side)
Barbed Fitting
CAUTION
Do not use copper tubing or existing copper condensate
lines for drain line.
Page 32
Page 33
6 - If unit will be started immediately upon completion
CONDENSATE TRAP LOCATIONS
minimum 1/4” per ft. toward trap
of installation, prime trap per procedure outlined in
Unit Start-Up section.
(Unit shownin upflow position withremote trap)
FieldProvidedVent
Min.1” AboveCondensate
Drain
1”
2” Max.
Connection
Min.
Condensate line must slope downward away from the trap
to drain. If drain level is above condensate trap, condensate pump must be used. Condensate drain line should
be routed within the conditioned space to avoid freezing of
condensate and blockage of drain line. If this is not possible, a heat cable kit may be used on the condensate trap
and line. Heating cable kit is available from Lennox in various lengths; 6 ft. (1.8m) - kit no. 26K68; 24 ft. (7.3m) - kit
no. 26K69; and 50 ft. (15.2m) - kit no. 26K70.
Furnace With Evaporator
Coil Using A Separate Drain
*5’ max.
PVCPipe Only
Trap CanBeInstalleda
Maximum 5’ From Furnac
e
To Drain
*Piping from furnace must slope down a
Figure 47
Furnace with Evaporator Coil Using a Separate Drain
(Unit shown in horizontal left-hand discharge position)
(Trap at coil is optional)
Field Provided Vent
(1” min. 2” max. above
condensate connection)
Condensate
Drain
Connection
Evaporator drain
line required
Figure 48
Evaporator
Coil
Drain
Pan
(Trap at coil is optional)
Piping from furnace and evaporator coil must slope down a minimum 1/4” per ft. toward trap
Field Provided Vent
(4” min. to 5” max. above
condensate connection)
4”min
5”max
5’ max.
PVC Pipe Only
Condensate
DrainConnection
.
Figure 49
Page 33
Page 34
IMPORTANT
When combining the furnace and evaporator coil
drains together, the A/C condensate drain outlet must
be vented to relieve pressure in order for the furnace
pressure switch to operate properly.
Condensate Trap With Optional Overflow Switch
From Evaporator Coil
HorizontalFurnace4 ” Min.to5” Max.above
condensatedrain connection)
FurnaceCondensate
Connection
Drain
Optional
Furnace with Evaporator
Coil Using a Common Drain
(Trap at coil is optional)
(1” min.to2” Max.above
condensatedrain connection)
Condensate
Connection
Drain
Figure 51
Evaporator drain
line required
Drain
Pan
Figure 50
Furnace with Evaporator Coil Using a Common Drain
(Unit shown in horizontal left−hand discharge position)
Evaporator
Coil
(Trap at coil is optional)
Piping from furnace and evaporator coil must slope
down a minimum 1/4” per ft. toward trap
Condensate Drain
Connection
5’ max.
PVC Pipe Only
Figure 52
4”min
5”max
(4” min.to5” Max.above
condensatedrain
connection)
Page 34
Page 35
Optional Condensate Drain Connection
TRAP / DRAIN ASSEMBLY USING 1/2” PVC OR 3/4” PVC
Adapter 3/4 inch slip X
3/4 inch mpt (not furnished)
90° Street Elbow
3/4 inch PVC
(not furnished)
Condensate Drain
Connection In Unit
90° Street Elbow
3/4 inch PVC
( furnished)
To
Trap
Optional DrainPipingFrom Trap
Drain Assembly for 1/2 inch Drain Pipe
1/2 inch PVC Pipe
(Not Furnished)
90° Elbow
1/2 inch PVC
(Not Furnished)
To
Drain Assembly for 3/4 inch Drain Pipe
Drain
1(25 mm) Min.
2 (50 mm) Max.
AboveTop Of
Condensate Drain
Connection In Unit
Elbow 3/4 inch PVC
90°
(Not Furnished)
1/2 inch PVC Pipe
(Not Furnished)
Adapter 3/4 inch slip X
3/4 inch mpt (not furnished)
V
ent
5 Feet
Maximum
3/4 inch PVC Pipe
(Not Furnished)
Coupling 3/4 inch slip X slip
Drain Trap
Assembly
(Furnished)
Condensate Drain
Connection In Unit
(Not Furnished)
90° Elbow
3/4 inch PVC
(Not Furnished)
To
Drain
DrainTrapAssembly
(Furnished)
7
(178)
Drain Trap
Clean Out
90° Elbow
3/4 inch PVC
(Not Furnished)
T
o
Coupling 3/4 inch slip X slip
Drain
DrainTrap Assembly with 1/2 inch Piping
1 (25 mm) Min. 2 (50 mm) Max. AboveTop
Of Condensate Drain Connection In Unit
(Not Furnished)
Vent
1/2 inch
Condensate Drain
Connection In Unit
To
Drain
Figure 53
DrainTr ap Assembly with 3/4 inch Piping
1 (25 mm) Min. 2 (50 mm) Max. AboveTop
Of Condensate Drain Connection In Unit
Vent
3/4 inch
Condensate Drain
Connection In Unit
To
Drain
Page 35
Page 36
Gas Piping
Gas supply piping should not allow more than 0.5”W.C.
drop in pressure between gas meter and unit. Supply gas
pipe must not be smaller than unit gas connection.
6 - In some localities, codes may require installation of
a manual main shut-off valve and union (furnished
by installer) external to the unit. Union must be of
the ground joint type.
CAUTION
If a exible gas connector is required or allowed by the
authority that has jurisdiction, black iron pipe shall be
installed at the gas valve and extend outside the furnace
cabinet. The exible connector can then be added
between the black iron pipe and the gas supply line.
WARNING
Do not over torque (800 in-lbs) or under torque (350 inlbs) when attaching the gas piping to the gas valve.
1 - Gas piping may be routed into the unit through either
the left- or right-hand side. Supply piping enters into
the gas valve from the side of the valve as shown
in gure 55. Connect the gas supply piping into the
gas valve. The maximum torque is 800 in lbs and
minimum torque is 350 in lbs when when attaching
the gas piping to the gas valve.
2 - When connecting gas supply, factors such as length
of run, number of ttings and furnace rating must
be considered to avoid excessive pressure drop.
Table 9 lists recommended pipe sizes for typical
applications.
NOTE - Use two wrenches when connecting gas
piping to avoid transferring torque to the manifold.
3 - Gas piping must not run in or through air ducts,
clothes chutes, chimneys or gas vents, dumb
waiters or elevator shafts. Center gas line through
piping hole. Gas line should not touch side of unit.
See Figure 55 and Figure 56.
4 - Piping should be sloped 1/4 inch per 15 feet (6mm
per 5.6m) upward toward the gas meter from the
furnace. The piping must be supported at proper
intervals, every 8 to 10 feet (2.44 to 3.05m), using
suitable hangers or straps. Install a drip leg in
vertical pipe runs to serve as a trap for sediment or
condensate.
5 - A 1/8” N.P.T. plugged tap or pressure post is located
on the gas valve to facilitate test gauge connection.
See Figure 62.
IMPORTANT
Compounds used on threaded joints of gas piping must
be resistant to the actions of liquied petroleum gases.
Leak Check
After gas piping is completed, carefully check all piping
connections (factory- and eld-installed) for gas leaks.
Use a leak detecting solution or other preferred means.
Never use an open ame to test for gas leaks. Check all
connections using a commercially available soap solution
made specically for leak detection.
The furnace must be isolated from the gas supply system
by closing its individual manual shut-off valve during any
pressure testing of the gas supply system at pressures
greater than or equal to 1/2 psig (3.48 kPa, 14 inches w.c.).
MANUAL MAIN SHUT-OFF
VALVE WILL NOT HOLD
NORMAL TEST PRESSURE
1/8” N.P. T. PLUGGED TAP
Figure 54
CAP
FURNACE
ISOLATE
GAS VALV E
IMPORTANT
When testing pressure of gas lines, gas valve must be
disconnected and isolated. See Figure 54. Gas valves
can be damaged if subjected to pressures greater than
1/2 psig (3.48 kPa).
WARNING
FIRE OR EXPLOSION HAZARD
Failure to follow the safety warnings exactly could result
in serious injury, death, or property damage. Never use
an open ame to test for gas leaks. Check all connections
using a commercially available soap solution made
specically for leak detection. Some soaps used for leak
detection are corrosive to certain metals. Carefully rinse
piping thoroughly after leak test has been completed.
Page 36
Page 37
Upflow Application
Left Side Piping
(Standard)
MANUAL
MAIN SHUT-OFF
VALV E
GROUND
JOINT
UNION
MANUAL
MAIN SHUT-OFF
VALV E
GROUND
JOINT
UNION
DRIP LEG
1/2” NPT
FIELD
PROVIDED
AND INSTALLED
NOTE - BLACK IRON PIPE ONLY TO BE ROUTED INSIDE OF CABINET
Figure 55
Horizontal Applications
Possible Gas Piping Configurations
MANUAL
MAIN SHUT-OFF
VALV E
GROUND
JOINT
UNION
DRIP LEG
Upflow Application
Right Side Piping
(Alternate)
Horizontal Application
Left-Side Air Discharge
1/2” NPT
MANUAL
MAIN SHUT-OFF
VALV E
GROUND
JOINT
UNION
DRIP LEG
DRIP LEG
Horizontal Application
Right-Side Air Discharge
FIELD
PROVIDED
AND INSTALLED
NOTE - BLACK IRON PIPE ONLY TO BE ROUTED INSIDE OF CABINET
Figure 56
MANUAL
MAIN SHUT-OFF
VALV E
GROUND
JOINT
UNION
DRIP LEG
Page 37
Page 38
TABLE 9
Gas Pipe Capacity - ft3/hr (m3/hr)
Nominal
Iron Pipe
Size Inches
(mm)
1/2
(12.7)
3/4
(19.05)
1
(25.4)
1-1/4
(31.75)
1-1/2
(38.1)
2
(50.8)
2-1/2
(63.5)
3
(76.2)
Internal
Diameter
inches
(mm)
.622
(17.799)
.824
(20.930)
1.049
(26.645)
1.380
(35.052)
1.610
(40.894)
2.067
(52.502)
2.469
(67.713)
3.068
(77.927)
10
(3.048)
172
(4.87)
360
(10.19)
678
(19.19)
1350
(38.22)
2090
(59.18)
4020
(113.83)
6400
(181.22)
11300
(319.98)
20
(6.096)
118
(3.34)
247
(7.000)
466
(13.19)
957
(27.09)
1430
(40.49)
2760
(78.15)
4400
(124.59)
7780
(220.30)
30
(9,144)
95
(2.69)
199
(5.63)
374
(10.59)
768
(22.25)
1150
(32.56)
2220
(62.86)
3530
(99.95)
6250
(176.98)
40
(12,192)
81
(2.29)
170
(4.81)
320
(9.06)
657
(18.60)
985
(27.89)
1900
(53.80)
3020
(85.51)
5350
(151.49)
Length of Pipe - feet (m)
50
(15.240)
72
(2.03)
151
(4.23)
284
(8.04)
583
(16.50)
873
(24.72)
1680
(47.57)
2680
(75.88)
4740
(134.22)
60
(18.288)
65
(1.84)
137
(3.87)
257
(7.27)
528
(14.95)
791
(22.39)
1520
(43.04)
2480
(70.22)
4290
(121.47)
70
(21.336)
60
(1.69)
126
(3.56)
237
(6.71)
486
(13.76)
728
(20.61)
1400
(39.64)
2230
(63.14)
3950
(111.85)
80
(24.384)
56
(1.58)
117
(3.31)
220
(6.23)
452
(12.79)
677
(19.17)
1300
(36.81)
2080
(58.89)
3670
(103.92)
NOTE - Capacity given in cubic feet (m3 ) of gas per hour and based on 0.60 specic gravity gas.
90
(27.432)
52
(1.47)
110
(3.11)
207
(5.86)
424
(12.00)
635
(17.98)
1220
(34.55)
1950
(55.22)
3450
(97.69)
100
(30,480)
50
(1.42)
104
(2.94)
195
(5.52)
400
(11.33)
600
(17.00)
1160
(32.844)
1840
(52.10)
3260
(92.31)
Page 38
Page 39
Electrical
INTERIOR MAKE-UP BOX INSTALLATION
WARNING
Electrostatic discharge can affect
electronic components. Take care
during unit installation and service to
ELECTROSTATIC
DISCHARGE
(ESD)
Precautions and
Procedures
protect the unit’s electronic controls.
Precautions will help to avoid control
exposure to electrostatic discharge
by putting the unit, the control and the
technician at the same electrostatic
potential. Touch hand and all tools
on an unpainted unit surface before
performing any service procedure to
neutralize electrostatic charge.
WARNING
Electric Shock Hazard. Can cause injury or
death. Unit must be properly grounded in
accordance with national and local codes.
WARNING
Fire Hazard. Use of aluminum wire with this product may
result in a re, causing property damage, severe injury
or death. Use copper wire only with this product.
The unit is equipped with a eld make-up box on the left
hand side of the cabinet. The make-up box may be moved
to the right side of the furnace to facilitate installation. If
the make-up box is moved to the right side, clip the wire
ties that bundle the wires together. The excess wire must
be pulled into the blower compartment. Secure the excess
wire to the existing harness to protect it from damage.
MAKE-UP
BOX
Right Side
The power supply wiring must meet Class I restrictions.
Protected by either a fuse or circuit breaker, select circuit
protection and wire size according to unit nameplate.
CAUTION
Failure to use properly sized wiring and circuit breaker
may result in property damage. Size wiring and circuit
breaker(s) per Product Specications bulletin (EHB) and
unit rating plate.
NOTE - Unit nameplate states maximum current draw.
Maximum over-current protection allowed is shown in table 10.
TABLE 10
EL296UHVMaximum Over-Current
045V36B, 070V36B,
090V36C, 090V48C,
110V48C
090V60C, 110V60C,
135V60D
Holes are on both sides of the furnace cabinet to facilitate
wiring.
Install a separate (properly sized) disconnect switch near
the furnace so that power can be turned off for servicing.
Before connecting the thermostat or the power wiring,
check to make sure the wires will be long enough for servicing at a later date. Remove the blower access panel to
check the length of the wire.
Complete the wiring connections to the equipment. Use
the provided unit wiring diagram and the eld wiring diagrams shown in table 11 and Figure 60. Use 18-gauge
wire or larger that is suitable for Class II rating for thermostat connections.
Electrically ground the unit according to local codes or, in
the absence of local codes, according to the current National Electric Code (ANSI/NFPA No. 70). A green ground
wire is provided in the eld make-up box. NOTE - The
EL296UHV furnace contains electronic components that
are polarity sensitive. Make sure that the furnace is wired
correctly and is properly grounded.
One line voltage “ACC” 1/4” spade terminal is provided on
the furnace integrated control. Any electronic air cleaner
or other accessory rated up to one amp can be connected to this terminal with the neutral leg of the circuit being
connected to the one of the provided neutral terminals.
See Figure 61 for control conguration. This terminal is
energized when the indoor blower is operating.
15
20
Figure 57
Refer to Figure 60 for unit schematic and eld wiring. See
Figure 58 and Figure 59 for icomfort Wi-Fi® thermostat
wiring in communicating applications. Table 11 shows DIP
switch and on-board link settings for non-communicating
thermostat applications. Typical wiring schematic is shown
in Figure 60.
Page 39
Page 40
An unpowered, normally open (dry) set of contacts with
a 1/4” spade terminal “HUM” are provided for humidier
connections and may be connected to 24V or 120V. Any
humidier rated up to one amp can be connected to these
terminals. In 120V humidier applications the neutral leg of
the circuit can be connected to one of the provided neutral
terminals. This terminal is energized in the heating mode.
Install the room thermostat according to the instructions
provided with the thermostat. See table 11 for eld wiring
connections in varying applications. If the furnace is being
matched with a heat pump, refer to the instruction packaged with the dual fuel thermostat.
Thermostat Selection
CAUTION
Field wiring for both communicating and noncommunicating applications is illustrated in diagrams,
which begin on the next page.
Non-Communicating
In non-communicating applications the EL296UHV
is designed to operate in a SINGLE-STAGE mode or
TWOSTAGE mode using a conventional thermostat.
For optimal performance in non-communicating applications, Lennox recommends use of a ComfortSense® 7000
high quality electronic digital thermostat or any other with
adjustable settings for 1st stage / 2nd stage on / off differentials and adjustable stage timers.
Communicating
In communicating applications the icomfort Wi-Fi® thermostat must be used. Refer to the instructions provided
with the thermostat for installation, set-up and operation.
In communicating system all unused thermostat wire in
the wire bundle needs to be terminated inside and out.
The extra wires can terminate on the ‘C” terminal of the
icomfort communication terminal strip. (RSBus). Using an
additional wire come off ”C” terminal and wire nut all the
extra wires together. Termination on the outdoor control
must match the indoor control.
Indoor Blower Speeds
Non-Communicating
When the thermostat is set to “FAN ON,” the indoor blower
will run continuously at a eld selectable percentage of
the second-stage cooling speed when there is no cooling
or heating demand. The factory default setting is 38% of
cool speed. When the EL296UHV is running in the heating mode,the indoor blower will run on the heating speed
designated by the positions of DIP switches 11, 12 and 13.
When there is a cooling demand, the indoor blower will
run on the cooling speed designated by the positions of
DIP switches 5 and 6. First stage cooling will run at 70%
cool speed.
Communicating
NOTE - When the EL296UHV is used with icomfort WiF® thermostat, proper indoor blower speed selections are
made by the communicating thermostat.
When the thermostat is set to “FAN ON,” the indoor blower
will run at setting determined during system conguration.
When there is a heating demand the fan will run on heat-
ing speeds for ring rate. When there is a cooling demand,
the fan will run on the rst stage and second stage cooling
speed set using the icomfort WiFi® thermostat in the installer setup mode. The factory default is based upon 400
CFM a ton.
Generator Use - Voltage Requirements
The following requirements must be kept in mind when
specifying a generator for use with this equipment:
• The furnace requires 120 volts (Range: 102 volts to
132 volts)
• The furnace operates at 60 Hz + 5% (Range: 57 Hz
to 63 Hz)
• The furnace integrated control requires both correct
polarity and proper ground. Both polarity and proper
grounding should be checked before attempting to
operate the furnace on either permanent or temporary power
• Generator should have a wave form distortion of
less than 5% THD (total harmonic distortion)
Page 40
Page 41
icomfort Wi-Fi
®
Thermostat with Furnace and
Non-Communicating Outdoor Unit
icomfort®ENABLED
FURNACE
icomfort Wi-Fi®
THERMOSTAT
NON-COMMUNICATING
OUTDOOR AIR
CONDITIONING UNIT -
1 OR 2 STAGE
icomfort Wi-Fi® Thermostat
icomfort
®
-Enabled Indoor Furnace
Non-Communicating Outdoor Air Conditioner
OPTIONAL
OUTDOOR
AIR SENSOR
OPTIONAL
DISCHARGE
AIR SENSOR
icomfort Wi-Fi® Thermostat with Furnace and
icomfort
®
-ENABLED Outdoor Unit
icomfort Wi-Fi® Thermostat
icomfort
®
-Enabled Indoor Furnace
icomfort
®
-Enabled Outdoor Air Conditioner or Heat Pump
icomfort®ENABLED
FURNACE
icomfort
®
- ENABLED
OUTDOOR AIR CONDITIONING
OR HEAT PUMP UNIT
OPTIONAL
OUTDOOR
AIR SENSOR
OPTIONAL
DISCHARGE
AIR SENSOR
CLIP ON-BOARD LINK
W915 (Y1 TO Y2) FOR
TWO-STAGE OPERATION
icomfort Wi-Fi®
THERMOSTAT
Indoor Unit
Controller
Outdoor Unit
Icomfort Wi-Fi
®
thermostat
Single wire to
terminal C
Single wire to
terminal C
Unused wires
Unused wires
Communicating systems using the Icomfort Wi-Fi
®
mostat wires between the thermostat and the furnace/air handler control and four
wires between
mostat cable with more than four wires is used, the extra wires must be properly
connected to avoid electrical noise. The wires must not be left disconnected.
Use wire nuts to bundle the four unused wires at each end of the cable. A
single wire should then be connected to the indoor unit end of the wire bundle
and attached to the “C” terminals as shown in the diagram above.
Figure 58
Page 41
Page 42
Optional Accessories for use with any icomfort Touch
NOTE: Icomfort Wi-Fi® THERMOSTAT SENSES HUMIDITY &
CONTROLS HUM CONTACTS TO CYCLE HUMIDIFIER BASED
QUIRED.
TIONS. BUILT INTO ALL icomfort by Lennox OUTDOOR UNITS).
®
System
120V CONNECTIONS
“HUM” CONTACT IS
CLOSED ANYTIME
HUMIDITY DEMAND
IS PRESENT
icomfort® ENABLED
FURNACE
sor (Required for
even heat)
Icomfort Wi-Fi
THERMOSTAT
®
RSBus
Maximum total
tions on the RSBus
is limited to 1500ft.
Wire gauge of
RSBus wire is 18.
®
icomfort
ENABLED OUTDOOR AIR
CONDITIONING OR HEAT
PUMP UNIT
ENABLED
®
FURNACE
icomfort
(POWER COMPANY INTERRUPTION SYSTEMS ARE
WIRED SAME AS OVERFLOW SWITCH)
HEPA BYPASS FILTER X2680 HEPA INTERLOCK KIT
NOTE: 24V UV LIGHT
APPLICATIONS
In an icomfort by Lennox
neither furnace nor air handler
transformer will have adequate VA
to power 24V UV light applications.
An additional transformer for UV
light applications is required.
system,
24V HUMIDIFIER CONNECTIONS
CONVENTIONAL NONCOMMUNICATING
SYSTEM
COMMUNICATING SYSTEM
*24V IN jumper not used in noncommunicating configuration
icomfort ENABLED
FURNACE
Icomfort Wi-Fi
THERMOSTAT
HVAC
EQUIPMENT
®
DEHUMIDIFIER
CONTROL
RfWGhGsCf
DH
HVAC EQUIP
CS 7000
THERMOSTAT
*24V IN
JUMPER
ENABLED
®
FURNACE
icomfort
LVCS VENTILATION CONTROL SYSTEM
ENABLED
®
FURNACE
icomfort
TOR COMMON WIRE
THROUGH CURRENT LOOP.
SEE HEPA INTERLOCK KIT
FOR INSTALLATION DETAILS
SEE LVCS VENTILATION
INSTRUCTIONS FOR DAMPER &
SENSOR WIRING
Figure 59
Page 42
STANDARD 1 OR 2 STAGE
AC OR HP UNIT
2 STAGE FURNACE
CUT R-DS
W914
NON-COMMUNICATING
SYSTEM WIRING
DS
R
COMMUNICATING
SYSTEM WIRING
Page 43
Thermostat
* Not required on all units.
1 Heat / 1 Cool
NOTE - Use DIP
switch 2 to set
second-stage
heat ON delay.
OFF-7 minutes.
ON-12 minutes.
DIP Switch Settings and On-Board Links
DIP Switch 1
Thermostat
Heating
Stages
ON
On Board Links Must Be Cut To Select
System Options
DO NOT CUT ANY
ON-BOARD LINKS
Wiring Connections
S1
T'STAT
FURNACE
TERM. STRIP
OUTDOOR
*
UNIT
1 Heat / 2 Cool
NOTE - Use DIP
switch 2 to set
second-stage
heat ON delay.
OFF-7 minutes.
ON-12 minutes.
1 Heat / 2 Cool
with t'stat with
humidity control
NOTE - Use DIP
switch 2 to set
second-stage
heat ON delay.
OFF-7 minutes.
ON-12 minutes.
ON
ON
CUT ON-BOARD LINK
W915
2 STAGE
COMPR
CUT ON-BOARD LINK
W915
2 STAGE
COMPR
CUT ON-BOARD LINK
W914
DEHUM
OR
HARMONY
S1
T'STAT
S1
T'STAT
FURNACE
TERM. STRIP
FURNACE
TERM. STRIP
*
o
OUTDOOR
UNIT
OUTDOOR
UNIT
*
Page 43
Page 44
DIP Switch 1
Thermostat
Thermostat
Heating
Stages
2 Heat / 2 CoolOFF
DIP Switch Settings and On-Board Links
On Board Links Must Be Cut To Select
System Options
CUT ON-BOARD LINK
W915
2 STAGE
COMPR
Wiring Connections
S1
T'STAT
FURNACE
TERM. STRIP
OUTDOOR
*
UNIT
2 Heat / 2 Cool
OFF
with t'stat with
humidity control
2 Heat / 1 Cool
OFF
with t'stat with
humidity control
2 Heat / 1 CoolOFF
CUT ON-BOARD LINK
W915
2 STAGE
COMPR
CUT ON-BOARD LINK
W914
DEHUM
OR
HARMONY
CUT ON-BOARD LINK
W914
DEHUM
OR
HARMONY
S1
T'STAT
S1
T'STAT
S1
T'STAT
FURNACE
TERM. STRIP
FURNACE
TERM. STRIP
FURNACE
TERM. STRIP
o
o
OUTDOOR
UNIT
*
OUTDOOR
UNIT
*
OUTDOOR
UNIT
* Not required on all units.
DO NOT CUT ANY
ON-BOARD LINKS
*
Page 44
Page 45
Thermostat
Dual Fuel
Single Stage
Heat Pump
ComfortSense
thermostat w/
DIP Switch Settings and On-Board Links
DIP Switch 1
Thermostat
Heating
Stages
OFF
On Board Links Must Be Cut To Select
System Options
CUT ON-BOARD LINK
W951
HEAT
PUMP
T'STAT
H
Wiring Connections
FURNACE
TERM. STRIP
HEAT PUMP
67M41*
bilities
Capable of 2
stage gas heat
control
Dual Fuel
Two Stage
Heat Pump
ComfortSense
thermostat w/
bilities
Capable of 2
stage gas heat
control
OFF
CUT ON-BOARD LINK
W915
2 STAGE
COMPR
CUT ON-BOARD LINK
W951
HEAT
PUMP
L
Y2
D
B
T
T
T'STAT
H
L
Y2
D
B
Y2
FURNACE
TERM. STRIP
67M41*
L
Y
outdoor
sensor
HEAT PUMP
L
Y2
out blue
T
T
outdoor
sensor
* Connect W1 to W1 ONLY if using defrost tempering kit 67M41
NOTE - Do NOT make a wire connection between the room thermostat L terminal and the L terminal of the furnace
integrated control.
Page 45
Page 46
Thermostat
Dual Fuel
Single Stage
Heat Pump
ComfortSense
thermostat w/
DIP Switch Settings and On-Board Links
DIP Switch 1
Thermostat
Heating
Stages
OFF
On Board Links Must Be Cut To Select
System Options
CUT ON-BOARD LINK
W951
HEAT
PUMP
Wiring Connections
T'STAT
H
FURNACE
TERM. STRIP
HEAT PUMP
67M41*
bilities
Capable of 2
stage gas heat
midification
control
Dual Fuel
Two Stage
Heat Pump
ComfortSense
thermostat w/
bilities
Capable of 2
stage gas heat
midification
OFF
CUT ON-BOARD LINK
W914
DEHUM
OR
HARMONY
CUT ON-BOARD LINK
W915
2 STAGE
COMPR
CUT ON-BOARD LINK
W951
HEAT
PUMP
CUT ON-BOARD LINK
W914
DEHUM
OR
HARMONY
L
Y2
D
B
T
T
T'STAT
H
L
Y2
D
B
Y2
FURNACE
TERM. STRIP
Y2
67M41*
L
Y
outdoor
sensor
HEAT PUMP
L
Y2
out blue
T
T
* Connect W1 to W1 ONLY if using defrost tempering kit 67M41
NOTE - Do NOT make a wire connection between the room thermostat L terminal and the L terminal of the furnace
integrated control.
Page 46
outdoor
sensor
Page 47
EL296UHV Schematic Wiring Diagram
Figure 60
Page 47
Page 48
Integrated Control
ACC
7 SEGMENT LED
FLAME SENSE
DIAGNOSTIC
PUSH BUTTON
DIP SWITCHES
OUTDOOR AIR
SENSOR
TERMINALS
DISCHARGE AIR
SENSOR
TERMINALS
TB83
COMMUNICATING
OUTDOOR
EQUIPMENT
TB84
COMMUNICATING
INDOOR
THERMOSTAT
HUM
LINE 1
I +I -CRI +I -
R
C
W1 W2 GY2Y1
NON-COMMUNICATINGNG
24V TERMINALS
CC
RDHLODS
HS/ CAI
INDOOR
BLOWER
CONNECTOR
12 PIN LOW
CONNECTOR
W915 Y1 TO Y2
2 STAGE COMPR
W951 R TO O
HEAT PUMP
W914 R TO DS
DEHUM OR
HARMONY
NEUTRAL
VOLTAGE
RS-BUS LINK (TB82, future use)
I+ = DATA HIGH CONNECTION
I - = DATA LOW CONNECTION
RS-BUS OUTDOOR (TB83)
R = 24VAC
I + = DATA HIGH CONNECTION
I - = DATA LOW CONNECTION
C = 24VAXC COMMON
RS-BUS INDOOR (TB84)
R = 24VAC
I + = DATA HIGH CONNECTION
I - = DATA LOW CONNECTION
C = 24VAXC COMMON
1/4” QUICK CONNECT TERMINALS
HUM = UNPOWERED NORMALLY OPEN (DRY) CONTACTS
XMFR = 120 VAC OUTPUT TO TRANSFORMER
LI = 120 VAC INPUT TO CONTROL
ACC = 120 VAC OUTPUT TO OPTIONAL ACCESSORY
NEUTRALS = 120 VAC NEUTRAL
THERMOSTAT CONNECTIONS (TB1)
DS = DEHUMIDIFICATION SIGNAL
W2 = HEAT DEMAND FROM 2ND STAGE T/STAT
W1 = HEAT DEMAND FROM 1ST STAGE T/STAT
R = CLASS 2 VOLTAGE TO THERMOSTAT
G = MANUAL FAN FROM T'STAT
C = THERMOSTAT SIGNAL GROUND CONNECTED TO
TRANSFORMER GRD (TR) & CHASIS GROUND (GRD)
Y1 = THERMOSTAT 1ST STAGE COOL SIGNAL
Y2 = THERMOSTAT 2ND STAGE COOL SIGNAL
O = THERMOSTAT SIGNAL TO HEAT PUMP
REVERSING VALV E
DH = DEHUMIDIFICATION OUTPUT COMMUNICATING
THERMOSTAT ONLY
L = USE ONLY WITH A COMMUNICATING THERMOSTAT
AND A NON-COMMUNICATING OUTDOOR UNIT
Figure 61
Page 48
Page 49
Integrated Control DIP Switch Settings -
Conventional Thermostat (non-communicating)
EL296UHV units are equipped with a two-stage, variable
speed integrated control. This control manages ignition
timing, heating mode fan off delays and indoor blower
speeds based on selections made using the control dip
switches and jumpers. The control includes an internal
watchguard feature which automatically resets the ignition
control when it has been locked out. After one hour of continuous thermostat demand for heat, the watchguard will
break and remake thermostat demand to the furnace and
automatically reset the control to relight the furnace.
Note: All icomfort settings are set at the icomfort Wi-Fi®
thermostat. See icomfort installation instruction. In icomfort communication system all DIP switch and clippable
link settings are ignored. For conventional thermostats
proceed with DIP switch and clippable link settings as outlined in the following.
Heating Operation DIP Switch Settings
Switch 1 -- Thermostat Selection -- This unit may be
used with either a single-stage or two-stage thermostat.
The thermostat selection is made using a DIP switch
which must be properly positioned for the particular application. The DIP switch is factory-positioned for use with a
twostage thermostat. If a single-stage thermostat is to be
used, the DIP switch must be repositioned.
a. Select “OFF” for two-stage heating operation controlled by a
two-stage heating thermostat (factory setting);
b. Select “ON” for two-stage heating operation controlled by
a single-stage heating thermostat. This setting provides a
timed delay before second-stage heat is initiated.
Switch 2 -- Second Stage Delay (Used with Single-
Stage Thermostat Only) -- This switch is used to determine the second stage on delay when a single-stage thermostat is being used. The switch is factory-set in the OFF
position, which provides a 7-minute delay before secondstage heat is initiated. If the switch is toggled to the ON
position, it will provide a 12-minute delay before secondstage heat is initiated. This switch is only activated when
the thermostat selector jumper is positioned for SINGLEstage thermostat use.
Switches 3 and 4 -- Blower-Off Delay -- The blower-on
delay of 30 seconds is not adjustable. The blower-off delay (time that the blower operates after the heating de-
mand has been satised) can be adjusted by moving
switches 3 and 4 on the integrated control. The unit is
shipped from the factory with a blower-off delay of 90 seconds. The blower off delay affects comfort and is adjustable to satisfy individual applications. Adjust the blower
off delay to achieve a supply air temperature between 90°
and 110°F at the exact moment that the blower is de-energized. Longer off delay settings provide lower supply air
temperatures; shorter settings provide higher supply air
temperatures.Table 12 provides the blower off timings that
will result from different switch settings.
TABLE 11
Blower Off Delay Switch Settings
Blower Off Delay
Seconds
60OnOff
90 (factory)OffOff
120OffOn
180OnOn
Switch 3Switch 4
Indoor Blower Operation DIP Switch Settings
Switches 5 and 6 -- Cooling Mode Blower Speed -- The
unit is shipped from the factory with the dip switches positioned for high speed (4) indoor blower motor operation
during the cooling mode. Table 13 provides the cooling
mode blower speeds that will result from different switch
settings. Switches 5 and 6 set the blower cfm for secondstage cool. The integrated control automatically ramps
down to 70% of the second-stage cfm for rst-stage cfm.
Refer to tables for corresponding cfm values. See Product
Specications for more detailed blower cfm tables.
TABLE 12
Cooling Mode Blower Speeds
SpeedSwitch 5Switch 6
LowOnOn
Medium LowOffOn
Medium HighOnOff
High (factory)OffOff
Switches 7 and 8 -- Cooling Blower Speed Adjustment
-- The unit is shipped from the factory with the dip switches
positioned for NORMAL (no) adjustment. The dip switches
may be positioned to adjust the blower speed by +10% or
-10% to better suit the application. Table 14 below provides blower speed adjustments that will result from different switch settings. Refer to tables for corresponding
cfm values. See Product Specications for more detailed
blower cfm tables.
TABLE 13
Cooling Blower Speed Adjustment
AdjustmentSwitch 7Switch 8
+10% (approx)OnOff
Factory DefaultOffOff
-10% (approx)OffOn
Switches 9 and 10 -- Cooling Mode Blower Speed
Ramping -- Blower speed ramping may be used to en-
hance dehumidication performance. The switches are
factory set at option A which has the greatest effect on
dehumidication performance. Table 15 provides the cooling mode blower speed ramping options that will result
from different switch settings. The cooling mode blower
mode blower speed ramping options are detailed on the
next page.
Page 49
Page 50
NOTE - The off portion of the selected ramp prole also
OFF
applies during heat pump operation in dual fuel applications.
TABLE 14
Cooling Mode Blower Speed Ramping
RampingSwitch 9Switch 10
A (Factory)OffOff
BOffOn
COnOff
DOnOn
Ramping Option A (Factory Selection)
• Motor runs at 50% for 30 seconds.
• Motor then runs at 82% for approximately 7-1/2
minutes.
• If demand has not been satised after 7-1/2 min-
utes, motor runs at 100% until demand is satised.
• Once demand is met, motor runs at 50% for 30
seconds then ramps down to stop.
1/2 MIN
50% CFM
7 1/2 MIN
82% CFM
COMPRESSOR DEMAND
100%
CFM
1/2 MIN
50% CFM
OFF
Ramping Option B
• Motor runs at 82% for approximately 7-1/2 minutes.
If demand has not been satised after 7-1/2 minutes, motor runs at 100% until demand is satised.
• Once demand is met, motor ramps down to stop.
Ramping Option D
• Motor runs at 100% until demand is satised.
• Once demand is met, motor ramps down to stop.
100% CFM
COMPRESSOR
DEMAND
OFFOFF
Switches 11, 12 and 13 -- Heating Mode Blower Speed
The switches are factory set to the OFF position which
provides factory default heat speed. Refer to table 16 for
switches 11, 12 and 13 that provided the corresponding
increases or decrease to both high and low heat demand.
TABLE 15
Heating Mode Blower Speeds
Heat SpeedSwitch 11Switch 12Switch 13
Increase 24%OnOnOn
Increase 18%OnOnOff
Increase 12%OnOffOn
Increae 6%On OffOff
Factory
OffOffOff
Default
Decrease 6%OffOffOn
Decrease
OffOnOff
12%
Decrease
OffOnOn
18%
Switches 14 and 15 -- Continuous Blower Speed --
Table 17 provides continuous blower speed adjustments
that will result from different switch settings.
OFF
7 1/2 MIN
82%CFM
COMPRESSOR DEMAND
100% CFM
Ramping Option C
• Motor runs at 100% until demand is satised.
• Once demand is met, motor runs at 100% for 45
seconds then ramps down to stop.
100% CFM
COMPRESSOR
DEMAND
100% CFM
45 SEC.
OFF
OFF
Page 50
TABLE 16
Continuous Blower Speed
Coninuous Blower SpeedSwitch 14Switch 15
28% of High Cool SpeedOffOn
38% of High Cool Speed
(Factory)
70% of High Cool SpeedOnOff
100% of High Cool SpeedOnOn
OffOff
Page 51
Blower Data
EL296UH045XV36B BLOWER PERFORMANCE (less lter)
BOTTOM RETURN AIR
0 through 0.8 in. w.g. (Heating) and 0 through 1.0 in. w.g. (Cooling) External Static Pressure Range
Cooling and heating speeds are based on a combination of DIP switch settings on the furnace control. Refer to Installation Instructions for specic DIP Switch Settings.
2
Factory default setting.
NOTES - The effect of static pressure is included in air volumes shown.
First stage HEAT is approximately 91% of the same second stage HEAT.
First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.
Continuous Fan Only speed is selectable at 28%, 38%, 70% and 100% of the selected second stage cooling speed - minimum 250 cfm.
Lennox iHarmony® Zoning System Applications - Minimum blower speed is 250 cfm.
Page 51
Page 52
Blower Data
EL296UH090XV36C BLOWER PERFORMANCE (less lter)
BOTTOM RETURN AIR
0 through 0.8 in. w.g. (Heating) and 0 through 1.0 in. w.g. (Cooling) External Static Pressure Range
Cooling and heating speeds are based on a combination of DIP switch settings on the furnace control. Refer to Installation Instructions for specic DIP Switch Settings.
2
Factory default setting.
NOTES - The effect of static pressure is included in air volumes shown.
First stage HEAT is approximately 91% of the same second stage HEAT.
First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.
Continuous Fan Only speed is selectable at 28%, 38%, 70% and 100% of the selected second stage cooling speed - minimum 380 cfm.
Lennox iHarmony® Zoning System Applications - Minimum blower speed is 250 cfm for EL296UH090XV60C and 380 cfm for EL296UH110XV48C.
Page 52
Page 53
Blower Data
EL296UH090XV60C BLOWER PERFORMANCE (less lter)
BOTTOM RETURN AIR
0 through 0.8 in. w.g. (Heating) and 0 through 1.0 in. w.g. (Cooling) External Static Pressure Range
Cooling and heating speeds are based on a combination of DIP switch settings on the furnace control. Refer to Installation Instructions for specic DIP Switch Settings.
2
Factory default setting.
NOTES - The effect of static pressure is included in air volumes shown.
First stage HEAT is approximately 91% of the same second stage HEAT.
First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.
Continuous Fan Only speed is selectable at 28%, 38%, 70% and 100% of the selected second stage cooling speed - minimum 380 cfm.
Lennox iHarmony® Zoning System Applications - Minimum blower speed is 450 cfm. for EL296UH090XV60C and 380 cfm for EL296UH110XV48C
Page 53
Page 54
Blower Data
EL296UH110XV60C BLOWER PERFORMANCE (less lter)
BOTTOM RETURN AIR
0 through 0.8 in. w.g. (Heating) and 0 through 1.0 in. w.g. (Cooling) External Static Pressure Range
HEATING
1
Heating Speed
DIP Switch
Settings
+24%13851965
+18%14751880
+12%13551790
+6%13701725
Factory Default12001630
–6%11401550
–12%10701460
–18%9801345
1
Cooling Speed
DIP Switch
Settings
LowMedium-LowMedium-High
+10601245134515451560174019302125
Factory Default9701145126513951405156517751945
–8851025111012501270142516101770
1
Cooling and heating speeds are based on a combination of DIP switch settings on the furnace control. Refer to Installation Instructions for specic DIP Switch Settings.
2
Factory default setting.
NOTES - The effect of static pressure is included in air volumes shown.
First stage HEAT is approximately 91% of the same second stage HEAT.
First stage COOL (two-stage air conditioning units only) is approximately 70% of the same second stage COOL speed position.
Continuous Fan Only speed is selectable at 28%, 38%, 70% and 100% of the selected second stage cooling speed - minimum 450 cfm.
Lennox iHarmony® Zoning System Applications - Minimum blower speed is 450 cfm.
Note: In icomfort systems with a conventional outdoor unit
(non-communicating), the on-board clippable links must
be set to properly congure the system.
WARNING
Carefully review all conguration information provided.
Failure to properly set DIP switches, jumpers and onboard links can result in improper operation!
Refer to table 18 for operation sequence in applications
including EL296UHV, a thermostat which features humidity control and a single-speed outdoor unit. Table 19 gives
the operation sequence in applications with a two-speed
outdoor unit.
On-Board Link W951 Heat Pump (R to O)
On-board link W951 is a clippable connection between
terminals R and O on the integrated control. W951 must
be cut when the furnace is installed in applications which
include a heat pump unit and a thermostat which features
On-Board Link W914 Dehum or Harmony (R to DS)
On-Board Link W914 Dehum or Harmony (R to DS) Onboard link W914, is a clippable connection between terminals R and DS on the integrated control. W914 must be
cut when the furnace is installed with either the Harmony
III zone control or a thermostat which features humidity
control. If the link is left intact the PMW signal from the
Harmony III control will be blocked and also lead to control
damage
dual fuel use. If the link is left intact, terminal “O” will remain energized eliminating the HEAT MODE in the heat
pump.
On-Board Link W915 2 Stage Compr (Y1 to Y2)
On-board link W915 is a clippable connection between
terminals Y1 and Y2 on the integrated control. W915 must
be cut if two-stage cooling will be used. If the Y1 to Y2 link
is not cut the outdoor unit will operate in second-stage
cooling only.
TABLE 17
OPERATING SEQUENCE
EL296UHV, Non-Communicating Thermostat with Humidity Control Feature and Single-Speed Outdoor Unit
OPERATING SEQUENCESYSTEM DEMANDSYSTEM RESPONSE
System
Condition
NO CALL FOR DEHUMIDIFICATION
Normal Operation1OnOnOnAcceptable
BASIC MODE (only active on a Y1 thermostat demand)
Normal Operation1OnOnOnAcceptable
Dehumidication
call
PRECISION MODE (operates independent of a Y1 demand)
Normal Operation1OnOnOnAcceptable
Dehumidication
Call
Dehumidication
Call Only
Dave Lennox ComfortSense® 7000 thermostat to use for this application - Y2081 4 heat / 2 cool
*Dehumidication blower speed is 70% of COOL speed for all units .
**In Precision mode, ComfortSense® 7000 thermostat will maintain room temperature up to 2 °F (1.2°C) cooler than room setting.
Step
2OnOnOnDemand0 VACHigh70%
2OnOnOnDemand0 VACHigh70%
1OnOnOnDemand0 VACHigh70%
Jumpers at indoor unit with a single stage outdoor unit. With Condensing unit - Cut
W914 (R to DS) on SureLight® control With Heat Pump - Cut W914 (R to DS) &
W951 (R to O) on SureLight® control
Thermostat DemandRelative Humidity
Y1OGW1StatusD
24
VAC
24
VAC
24
VAC
Compre
ssor
High100%
High100%
High100%
Blower
CFM
(cool)
Comments
Compressor and
indoor blower follow
thermostat demand
ComfortSense® 7500
thermostat energizes
Y1 and de-energizes
D on a call for de-
humidication
Dehumidication
mode begins when
humidity is greater
than set point
ComfortSense®
7500 thermostat will
try to maintain room
humidity setpoint by
allowing the room
space to maintain
a cooler room
thermostat setpoint**
Page 55
Page 56
TABLE 18
OPERATING SEQUENCE
SL280UHV, Non-Communicating Thermostat with Humidity Control Feature and Two-Speed Outdoor Unit
OPERATING
SEQUENCE
System
Condition
Step
NO CALL FOR DEHUMIDIFICATION
Normal Operation
Y1
Normal Operation
Y2
1OnOnOnAcceptable
2OnOnOnOnAcceptable
ROOM THERMOSTAT CALLS FOR FIRST STAGE COOLING
BASIC MODE (only active on a Y1 thermostat demand)
Normal Operation1OnOnOnAcceptable
Dehumidication
call
2OnOnOnOnDemand
PRECISION MODE (operates independent of a Y1 demand)
Normal Operation1OnOnOnAcceptable
Dehumidication
Call
Dehumidication
Call Only
2OnOnOnOnDemand
1OnOnOnOnDemand
ROOM THERMOSTAT CALLS FOR FIRST AND SECOND STAGE COOLING
BASIC MODE (only active on a Y1 thermostat demand)
Normal Operation1OnOnOnOnAcceptable
Dehumidication
Call
2OnOnOnOnDemand
PRECISION MODE (operates independent of a Y1 thermostat demand)
Normal Operation1OnOnOnAcceptable
Dehumidication
Call
Dehumidication
Call ONLY
2OnOnOnOnDemand
1OnOnOnOnDemand
Jumpers at indoor unit with a two stage outdoor unit
Cut factory jumper from Y1 to Y2 or cut W915 (Y1 to Y2)
With Condensing unit - Cut W914 (R to DS) on SureLight® control
With Heat Pump - Cut W914 (R to DS) & W951 (R to O) on SureLight® control
Dave Lennox ComfortSense® 7000 thermostat to use for this application - Y2081 4 heat / 2 cool
**Dehumidication blower speed is, reduced to 70% of COOL.
***In Precision mode, ComfortSense® 7000 thermostat will maintain room temperature up to 2 °F (1.2°C) cooler than room setting.
SYSTEM DEMANDSYSTEM RESPONSE
Thermostat DemandRelative Humidity
Y1Y2OGW1W2StatusD
24
VAC
24
VAC
24
VAC
0
VAC
24
VAC
0
VAC
0
VAC
24
VAC
0
VAC
24
VAC
0
VAC
0
VAC
Compre
ssor
Low70%
High100%
Low70%
High70%
Low70%
High70%
High70%
High100%
High70%
Low70%
High70%
High70%
Blower
CFM
(cool)
Comments
Compressor and indoor
blower follow thermostat
demand
ComfortSense® 7500
thermostat energizes Y1
and de-energizes D on a
call for de-humidication
Dehumidication mode
begins when humidity is
greater than set point
ComfortSense® 7500
thermostat will try to
maintain room humidity
setpoint by allowing the
room space to maintain
a cooler room thermostat
setpoint**
ComfortSense® 7500
thermostat energizes Y2
and de-energizes D on a
call for de-humidication
Dehumidication mode
begins when humidity is
greater than set point
ComfortSense® 7500
thermostat will try to
maintain room humidity
setpoint by allowing the
room space to maintain
a cooler room thermostat
setpoint***
Page 56
Page 57
Unit Start Up
FOR YOUR SAFETY READ BEFORE OPERATING
WARNING
Do not use this furnace if any part has been underwater.
A ood-damaged furnace is extremely dangerous.
Attempts to use the furnace can result in re or explosion.
Immediately call a qualied service technician to inspect
the furnace and to replace all gas controls, control
system parts, and electrical parts that have been wet or
to replace the furnace, if deemed necessary.
WARNING
Danger of explosion. Can cause injury or
product or property damage. If overheating
occurs or if gas supply fails to shut off, shut
off the manual gas valve to the appliance
before shutting off electrical supply.
CAUTION
Before attempting to perform any service or maintenance,
turn the electrical power to unit OFF at disconnect switch.
BEFORE LIGHTING the unit, smell all around the furnace
area for gas. Be sure to smell next to the oor because
some gas is heavier than air and will settle on the oor.
The gas valve on the EL296UHV is equipped with a gas
control switch (lever). Use only your hand to moveswitch.
Never use tools. If the the switch will not move by hand,
do not try to repair it. Force or attempted repair may result
in a re or explosion.
Placing the furnace into operation:
EL296UHV units are equipped with an automatic hot
surface ignition system. Do not attempt to manually light
burners on this furnace. Each time the thermostat calls for
heat, the burners will automatically light. The ignitor does
not get hot when there is no call for heat on these units.
Priming Condensate Trap
The condensate trap should be primed with water prior
to start-up to ensure proper condensate drainage. Either
pour 10 . oz. (300 ml) of water into the trap, or follow
these steps to prime the trap:
1 - Follow the lighting instructions to place the unit into
operation.
2 - Set the thermostat to initiate a heating demand.
3 - Allow the burners to re for approximately 3 minutes.
4 - Adjust the thermostat to deactivate the heating
demand.
5 - Wait for the combustion air inducer to stop. Set the
thermostat to initiate a heating demand and again
allow the burners to re for approximately 3 minutes.
6 - Adjust the thermostat to deactivate the heating
demand and wait for the combustion air inducer to
stop. At this point, the trap should be primed with
sufcient water to ensure proper condensate drain
operation.
WARNING
If you do not follow these instructions exactly, a re or
explosion may result causing property damage, personal
injury or death.
Gas Valve Operation (Figure 62)
1 - STOP! Read the safety information at the beginning
of this section.
2 - Set the thermostat to the lowest setting.
3 - Turn off all electrical power to the unit.
4 - This furnace is equipped with an ignition device
which automatically lights the burners. Do not try to
light the burners by hand.
5 - Remove the access panel.
6 - Move gas valve switch to OFF. See gure 62.
7 - Wait ve minutes to clear out any gas. If you then
smell gas, STOP! Immediately call your gas supplier
from a neighbor’s phone. Follow the gas supplier’s
instructions. If you do not smell gas go to next step.
8 - Move gas valve switch to ON. See Figure 62.
WHITE RODGERS GAS VALVE
INLET PRESSURE POST
GAS VALV E SHOWN IN ON POSITION
9 - Replace the access panel.
10 - Turn on all electrical power to to the unit.
11 - Set the thermostat to desired setting.
NOTE - When unit is initially started, steps 1 through
11 may need to be repeated to purge air from gas
line.
12 - If the appliance will not operate, follow the
instructions “Turning Off Gas to Unit” and call your
service technician or gas supplier.
Turning Off Gas to Unit
1 - Set the thermostat to the lowest setting.
2 - Turn off all electrical power to the unit if service is to
be performed.
3 - Remove the access panel.
MANIFOLD
PRESSURE TAP
Figure 62
HIGH FIRE ADJUSTMENT
SCREW
(under cap)
Page 57
Page 58
4 - Move gas valve switch to OFF.
5 - Replace the access panel.
Failure To Operate
If the unit fails to operate, check the following:
1 - Is the thermostat calling for heat?
2 - Are access panels securely in place?
3 - Is the main disconnect switch closed?
4 - Is there a blown fuse or tripped breaker?
5 - Is the lter dirty or plugged? Dirty or plugged lters
will cause the limit control to shut the unit off.
6 - Is gas turned on at the meter?
7 - Is the manual main shut-off valve open?
8 - Is the internal manual shut-off valve open?
9 - Is the unit ignition system in lockout? If the unit
locks out again, inspect the unit for blockages.
Heating Sequence Of Operation
1 - When thermostat calls for heat, combustion air
inducer starts.
2 - Combustion air pressure switch proves blower
operation. Switch is factory set and requires no
adjustment.
3 - After a 15-second prepurge, the hot surface ignitor
energizes.
4 - After a 20-second ignitor warm-up period, the gas
valve solenoid opens. A 4-second trial for ignition
period begins.”
5 - Gas is ignited, ame sensor proves the ame, and
the combustion process continues.
6 - If ame is not detected after rst ignition trial,
the ignition control will repeat steps 3 and 4 four
more times before locking out the gas valve
(“WATCHGUARD” ame failure mode). The ignition
control will then automatically repeat steps 1 through
6 after 60 minutes. To interrupt the 60-minute
“WATCHGUARD” period, move thermostat from
“Heat” to “OFF” then back to “Heat”. Heating
sequence then restarts at step 1.
Gas Pressure Adjustment
Gas Flow (Approximate)
TABLE 19
GAS METER CLOCKING CHART
Seconds for One Revolution
EL296
Unit
-04580160200400
-07055110136272
-0904182102204
-110336682164
-135275468136
Natural-1000 btu/cu ft LP-2500 btu/cu ft
NaturalLP
1 cu ft
Dial
2 cu ft
Dial
1 cu ft
Dial
2 cu ft
Dial
Furnace should operate at least 5 minutes before checking gas ow. Determine time in seconds for two revolutions of gas through the meter. (Two revolutions assures
a more accurate time.) Divide by two and compare to time
in table 20. If manifold pressure matches table 22 and rate
is incorrect, check gas orices for proper size and restriction. Remove temporary gas meter if installed.
NOTE - To obtain accurate reading, shut off all other gas
appliances connected to meter.
Supply Pressure Measurement
An inlet post located on the gas valve provides access
to the supply pressure. See Figure 62. Back out the 3/32
hex screw one turn, connect a piece of 5/16 tubing and
connect to a manometer to measure supply pressure. See
table 22 for supply line pressure.
On multiple unit installations, each unit should be checked
separately, with and without units operating. Supply pressure must fall within range listed in table 22.
Manifold Pressure Measurement
NOTE - Pressure test adapter kit (10L34) is available from
Lennox to facilitate manifold pressure measurement.
A manifold pressure post located on the gas valve provides access to the manifold pressure. See Figure 62.
Back out the 3/32 hex screw one turn, connect a piece
of 5/16 tubing and connect to a manometer to measure
manifold pressure.
To correctly measure manifold pressure, the differential
pressure between the positive gas manifold and the negative burner box must be considered.
1 - Connect the test gauge positive side “+“ to manifold
pressure tap on gas valve as noted above.
2 - Tee into the gas valve regulator vent hose and
connect to test gauge negative “-”.
3 - Ignite unit on low re and let run for 5 minutes to
allow for steady state conditions.
4 - After allowing unit to stabilize for 5 minutes, record
manifold pressure and compare to value given in
table 22.
5 - If necessary, make adjustments. Figure 62 shows
location of high re and low re adjustment screws.
6 - Repeat steps 3, 4 and 5 on high re. See values in
table 22.
7 - Shut unit off and remove manometer as soon as
an accurate reading has been obtained. Turn the
supply and manifold 3/32” hex screws one revolution
back into the gas valve.
8 - Start unit and perform leak check. Seal leaks if
found.
Page 58
Page 59
Proper Cumbustion
Furnace should operate minimum 15 minutes with correct
manifold pressure and gas ow rate before checking combustion. Take combustion sample beyond the ue outlet
and compare to the tables below.
TABLE 20
EL296
Model
CO2% For NatCO2% For L.P
Low FireHigh FireLow FireHigh Fire
0455.4 - 6.47.5 - 8.56.4 - 7.48.8 - 9.8
0705.3 - 6.37.4 - 8.46.3 - 7.38.7 - 9.7
0905.8 - 6.87.6 - 8.66.8 - 7.88.9 - 9.9
High Altitude
NOTE - In Canada, certication for installations at elevations over 4500 feet (1372 m) is the jurisdiction of local
authorities.
Units may be installed at altitudes up to 10,000 ft. above
sea level. See table 22 for de-rate manifold values. Units
installed at altitude of 7501 - 10,000 feet require an orice
change. Units installed at altitude of 4501 - 10,000 feet
require a pressure switch change which can be ordered
separately. Table 23 lists conversion kit and pressure
switch requirements at varying altitudes.
The combustion air pressure switch is factory-set and requiresno adjustment.
1106.1 - 7.18.0 - 9.07.1 - 8.19.3 - 10.3
1356.1 - 7.17.8 - 8.87.1 - 8.29.1 - 10.1
The maximum carbon monoxide reading should not exceed 100ppm.
TABLE 21
Manifold and Supply Line Pressure 0-10,000ft.
Manifold Pressure in. wg.Supply Line
UnitGas
Natuarl1.73.51.63.31.53.21.53.11.73.54.513.0
All
Sizes
NOTE - A natural to L.P. propane gas changeover kit is necessary to convert this unit. Refer to the changeover kit installation instruction
for the conversion procedure.
LP/Propane Conversion Kit and Pressure Switch Requirements at Varying Altitudes
Natural to
Unit
045
07014A5414A53
09014A5714A54
11014A4614A51
13514A4914A51
* Conversion requires installation of a gas valve manifold spring which is provided with the gas conversion kit. Pressure switch is factory
set. No adjustment necessary. All models use the factory-installed pressure switch from 0-4500 feet (0-1370 m).
Testing for Proper Venting and Sufcient Combustion Air for Non-Direct Vent Applications
8 - If improper venting is observed during any of the
WARNING
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.
After the EL296UHV gas furnace has been started, the
following test should be conducted to ensure proper vent-
ing and sufcient combustion air has been provided to the
EL296UHV as well as to other gas-red appliances which
are separately vented.
If a EL296UHV furnace replaces a Category I furnace
which was commonly vented with another gas appliance,
the size of the existing vent pipe for that gas appliance
must be checked. Without the heat of the original furnace
ue products, the existing vent pipe is probably oversized
for the single water heater or other appliance. The vent
should be checked for proper draw with the remaining appliance.
The test should be conducted while all appliances (both
in operation and those not in operation) are connected to
the venting system being tested. If the venting system has
been installed improperly, or if provisions have not been
made for sufcient amounts of combustion air, corrections
must be made as outlined in the previous section.
1 - Seal any unused openings in the venting system.
2 - Visually inspect the venting system for proper
size and horizontal pitch. Determine there is no
blockage or restriction, leakage, corrosion, or other
deciencies which could cause an unsafe condition.
3 - To the extent that it is practical, close all building
doors and windows and all doors between the
space in which the appliances connected to the
venting system are located and other spaces of the
building.
4 - Close replace dampers.
5 - Turn on clothes dryers and any appliances not
connected to the 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.
6 - Follow the lighting instruction to place the appliance
being inspected into operation. Adjust thermostat
so appliance will operate continuously.
7 - Use the ame of match or candle to test for spillage
of ue gases at the draft hood relief opening after 5
minutes of main burner operation.
above tests, the venting system must be corrected
or sufcient combustion/make-up air must be
provided. The venting system should be re-sized
to approach the minimum size as determined by
using the appropriate tables in appendix G in the
current standards of the National Fuel Gas Code
ANSI-Z223.1/NPFA 54 in the U.S.A., and the
appropriate Natural Gas and Propane appliances
venting sizing tables in the current standard of the
CSA-B149 Natural Gas and Propane Installation
Codes in Canada.
9 - After determining that each appliance remaining
connected to the common venting system properly
vents when tested as indicated in step 3, return
doors, windows, exhaust fans, replace dampers
and any other gas-burning appliance to their
previous condition of use.
Repair Parts
The following repair parts are available through Lennox
dealers. When ordering parts, include the complete furnace model number listed on the CSA nameplate -- Example: EL296UHV045P24B-01. All service must be performed by a licensed professional installer (or equivalent),
service agency, or gas supplier.
Cabinet Parts
Outer access panel
Blower access panel
Top Cap
Control Panel Parts
Transformer
Integrated control board
Door interlock switch
Blower Parts
Blower wheel
Motor
Motor mounting frame
Motor capacitor
Blower housing cutoff plate
Heating Parts
Flame Sensor
Heat exchanger assembly
Gas manifold
Combustion air inducer
Gas valve
Main burner cluster
Main burner orices
Pressure switch
Ignitor
Primary limit control
Flame rollout switches
Page 60
Page 61
Other Unit Adjustments
NOTE - See troubleshooting ow charts if any safety
switches are found to be open.
Primary Limit.
The primary limit is located on the heating compartment
vestibule panel. This limit is factory set and requires no
adjustment.
Flame Rollout Switches (Two)
These manually reset switches are located on the front of
the burner box.
Pressure Switch
The pressure switch is located in the heating compartment
on the cold end header box. This switch checks for proper
combustion air inducer operation before allowing ignition
trial. The switch is factory-set and must not be adjusted.
Temperature Rise
Place the unit into operation with a second-stage heating
demand. After supply and return air temperatures have
stabilized, check the temperature rise. If necessary, adjust
the heating blower speed to maintain the temperature rise
within the range shown on the unit nameplate. Increase
the blower speed to decrease the temperature rise. Decrease the blower speed to increase the temperature rise.
Failure to properly adjust the temperature rise may cause
erratic limit operation.
Electrical
1 - Check all wiring for loose connections.
2 - Check for the correct voltage at the furnace (furnace
operating). Correct voltage is 120VAC + 10%
3 - Check amp-draw on the blower motor with blower
access panel in place.
Unit Nameplate__________Actual__________
Exhaust and Air Intake Pipe
1 - Check exhaust and air intake connections for
tightness and to make sure there is no blockage.
2 - Is pressure switch closed? Obstructed exhaust pipe
will cause unit to shut off at pressure switch. Check
termination for blockages.
3 - Obstructed pipe or termination may cause rollout
switches to open. Reset manual ame rollout
switches on burner box assembly if necessary.
Heating Sequence of Operation
Electronic Ignition
The two-stage, variable speed integrated control used in
EL296UHV units has an added feature of an internal
Watchguard control. The feature serves as an automatic
reset device for ignition control lockout caused by ignition
failure. After one hour of continuous thermostat demand
for heat, the Watchguard will break and remake thermostat demand to the furnace and automatically reset the
control to begin the ignition sequence.
NOTE - The ignition control thermostat selection DIP
switch is factory-set in the “TWO-STAGE” position.
Applications Using a Two-Stage Thermostat
See Figure 63 for ignition control sequence
A - Heating Sequence -- Integrated Control Thermostat
Selection DIP Switch 1 OFF in “Two-Stage” Position
(Factory Setting)
1 - On a call for heat, thermostat rst-stage contacts
close sending a signal to the integrated control. The
integrated control runs a self-diagnostic program
and checks high temperature limit switches for
normally closed contacts and pressure switches for
normally open contacts. The combustion air inducer
is energized at low speed.
2 - Once the control receives a signal that the low
pressure switch has closed, the combustion air
inducer begins a 15-second pre-purge in low speed.
NOTE - If the low re pressure switch does not close
the combustion air inducer will switch to high re.
After a 15 second pre-purge the high re pressure
switch will close and the unit will begin operation on
high re. After 10 to 20 seconds of high re operation the unit will switch to low re..
3 - After the pre-purge is complete, a 20-second initial
ignitor warm-up period begins. The combustion air
inducer continues to operate at low speed.
4 - After the 20-second warm-up period has ended,
the gas valve is energized on low re (rst stage)
and ignition occurs. At the same time, the control
module sends a signal to begin an indoor blower
30-second ON-delay. When the delay ends, the
indoor blower motor is energized on the low re
heating speed, the HUM contacts close energizing
the humidier and 120V ACC terminal is energized.
The furnace will continue this operation as long as
the thermostat has a rst-stage heating demand.
5 - If second-stage heat is required, the thermostat
second- stage heat contacts close and send a signal
to the integrated control. The integrated control
initiates a 30-second second-stage recognition
delay.
6 - At the end of the recognition delay, the integrated
control energizes the combustion air inducer at
high speed. The control also checks the high re
(second stage) pressure switch to make sure it is
closed. The high re (second stage) gas valve is
energized and the indoor blower motor is energized
for operation at the high re heating speed.
7 - When the demand for high re (second stage) heat
is satised, the combustion air inducer is switched
to the low-re heating speed and the high-re
(second stage) gas valve is de-energized. The
low-re (rst stage) gas valve continues operation.
The indoor blower motor is switched to the low-re
heating speed.
8 - When the thermostat demand for low-re (rst
stage) heat is satised, the gas valve is deenergized and the eld-selected indoor blower off
delay begins. The combustion air inducer begins a
5-second post-purge period.
9 - When the combustion air post-purge period is
complete, the inducer and the HUM contacts are
de-energized. The indoor blower is de-energized at
the end of the off delay as well as the 120V ACC
terminals.
Page 61
Page 62
Applications Using A Single-Stage Thermostat
HEATING OPERATION WITH SINGLE STAGE THERMOSTAT
r
See Figure 64 for ignition control sequence
B - Heating Sequence -- Integrated Control Thermostat
Selection DIP Switch 1 ON in “Single-Stage” Position
NOTE - In these applications, two-stage heat will be initiated by the integrated control if heating demand has not
been satised after the eld adjustable period (7 or 12
minutes).
1 - On a call for heat, thermostat rst-stage contacts
close sending a signal to the integrated control. The
integrated control runs a self-diagnostic program
and checks high temperature limit switches for
normally closed contacts and pressure switches for
normally open contacts. The combustion air inducer
is energized at low speed.
2 - Once the control receives a signal that the low
pressure switch has closed, the combustion air
inducer begins a 15-second pre-purge in low speed.
NOTE - If the low re pressure switch does not close
the combustion air inducer will switch to high re.
After a 15 second pre-purge the high re pressure
switch will close and the unit will begin operation on
high re. After 10 to 20 seconds of high re operation the unit will switch to low re.
3 - After the pre-purge is complete, a 20-second initial
ignitor warm-up period begins. The combustion air
inducer continues to operate at low speed.
4 - After the 20-second warm-up period has ended,
the gas valve is energized on low re (rst stage)
and ignition occurs. At the same time, the control
module sends a signal to begin an indoor blower
30-second ON-delay. When the delay ends, the
indoor blower motor is energized on the low re
heating speed and the HUM contacts are energized.
The integrated control also initiates a second-stage
on delay (factory-set at 7 minutes; adjustable to 12
minutes).
5 - If the heating demand continues beyond the
secondstage on delay, the integrated control
energizes the combustion air inducer at high speed.
The control also checks the high re (second stage)
pressure switch to make sure it is closed. The high
re (second stage) gas valve is energized and the
indoor blower motor is energized for operation at
the high re heating speed.
6 - When the thermostat heating demand is satised,
the combustion air inducer begins a 5-second low
speed post-purge. The eld-selected indoor blower
off delay begins. The indoor blower operates at the
low-re heating speed.
7 - When the combustion air post-purge period is
complete, the inducer and the HUM contacts are
de-energized. The indoor blower is de-energized at
the end of the off delay as well as the 120V ACC
terminals.
HEATING OPERATION WITH TWO-STAGE THERMOSTAT
15
Pre-Purge
Ignitor Warm-up
35
30 seconds
39
30* second
Trial For
Ignition
RECOGNITION PERIOD
blower
“on” delay
ON
1 stg heat demand
low speed CAI
ignitor
low fire gas valve
indoor blower low heat
2 stg heat demand
high speed CAI
high fire gas valve
indoor blower high heat
OFF
* Conventional thermostat 30 seconds, icomfort Touch® thermostat set for 30 adjustable 15 to 45 seconds.
1
Figure 63
ON
OFF
heat demand
low speed CAI
ignitor
low fire gas valve
indoor blower low heat
7 or 12 minutes after heating demand begins, furnace switches to high fire (depends on setting)
thermostat set for 30 adjustable 15 to 45 seconds.
80
5 SEC80
Post
Purge
blower
delay
5 SEC
Post
Purge
“off”
blowe
“off”
delay
Figure 64
Page 62
Page 63
Service
WARNING
ELECTRICAL SHOCK, FIRE,
OR EXPLOSION HAZARD.
Failure to follow safety warnings exactly could result in
dangerous operation, serious injury, death or property
damage.
Improper servicing could result in dangerous operation,
serious injury, death, or property damage. Before
servicing, disconnect all electrical power to furnace.
When servicing controls, label all wires prior to
disconnecting. Take care to reconnect wires correctly.
Verify proper operation after servicing.
WARNING
The blower access panel must be securely in place when
the blower and burners are operating. Gas fumes, which
could contain carbon monoxide, can be drawn into living
space resulting in personal injury or death.
Annual Furnace Maintenance
At the beginning of each heating season, and to comply
with the Lennox Limited Warranty, your system should
be checked as follows:
1 - Check wiring for loose connections, voltage at
indoor unit and amperage of indoor motor.
2 - Check the condition of the belt and shaft bearings
if applicable.
3 - Inspect all gas pipe and connections for leaks.
4 - Check the cleanliness of lters and change if
necessary (monthly).
5 - Check the condition and cleanliness of burners and
heat exchanger and clean if necessary.
6 - Check the cleanliness of blower assembly and
clean the housing, blower wheel and blower motor
if necessary.
7 - Inspect the condensate drain and trap for leaks and
cracks. The drain and trap must also be cleaned
and the trap must be primed with water. Inspect the
rubber hoses connected to the pressure switches for
cracks or loose connections, replace as necessary.
Remove the rubber hoses from the cold end header
box and inspect for any blockage, clean as needed.
If strainers are installed in the hoses remember to
remove and clean before reinstalling the hoses.
8 - Evaluate the heat exchanger integrity by inspecting
the heat exchanger per the AHRI heat exchanger
inspection procedure. This procedure can be
viewed at www.ahrinet.org.
9 - Ensure sufcient combustion air is available to the
furnace. Fresh air grilles and louvers (on the unit
and in the room where the furnace is installed)
must be properly sized, open and unobstructed to
provide combustion air.
10 - Inspect the furnace intake and exhaust pipes to
make sure they are in place, structurally sound,
without holes, blockage or leakage and the
exhaust pipe is sloped toward the furnace. Inspect
terminations to ensure they are free of obstructions
and are structurally sound. Inspect the furnace
return air duct connection to ensure the duct is
sealed to the furnace. Check for air leaks on supply
and return ducts and seal where necessary.
11 - Inspect the furnace return air duct connection to
ensure the duct is sealed to the furnace. Check for
air leaks on supply and return ducts and seal where
necessary.
12 - Check the condition of the furnace cabinet insulation
and repair if necessary.
13 - Perform a complete combustion analysis during the
furnace inspection to ensure proper combustion
and operation. Consult Service Literature for proper
combustion values.
14 - Verify operation of CO detectors and replace
batteries as required.
Perform a general system test. Turn on the furnace to
check operating functions such as the start-up and shutoff operation.
1 - Check the operation of the ignition system, inspect
and clean ame sensor. Check microamps before
and after. Check controls and safety devices (gas
valve, ame sensor, temperature limits). Consult
Service Manual for proper operating range. Thermal
Limits should be checked by restricting airow and
not disconnecting the indoor blower. For additional
details, please see Service and Application Note
H049.
2 - Verify that system total static pressure and airow
settings are within specic operating parameters.
3 - Clock gas meter to ensure that the unit is operating
at the specied ring rate for each stage of
operation. Check the supply pressure and the
manifold pressure on both low re and high re. If
manifold pressure adjustment is necessary, consult
the Service Literature for unit specic information
on adjusting gas pressure. Not all gas valves are
adjustable. Verify correct temperature rise.
Page 63
Page 64
Winterizing and Condensate Trap Care
1 - Turn off power to the furnace.
2 - Have a shallow pan ready to empty condensate
water.
3 - Remove the clean out cap from the condensate trap
and empty water. Inspect the trap then reinstall the
clean out cap.
Cleaning The Burner Assembly
If cleaning the burner assembly becomes necessary, follow the steps below:
1 - Turn off electrical and gas power supplies to furnace.
Remove upper and lower furnace access panels.
2 - Disconnect the wires from the gas valve.
3 - Remove the burner box cover (if equipped).
4 - Disconnect the gas supply line from the gas valve.
Remove gas valve/manifold assembly.
5 - Mark and disconnect sensor wire from the sensor.
Disconnect wires from ame rollout switches.
6 - Disconnect combustion air intake pipe. It may be
necessary to cut the existing pipe to remove burner
box assembly.
7 - Remove four screws which secure burner box
assembly to vest panel. Remove burner box from
the unit.
8 - Use the soft brush attachment on a vacuum cleaner
to gently clean the face of the burners. Visually
inspect the inside of the burners and crossovers for
any blockage caused by foreign matter. Remove
any blockage.
9 - Reinstall the burner box assembly using the existing
four screws. Make sure that the burners line up in
the center of the burner ports.
10 - Reconnect the sensor wire and reconnect the 2-pin
plug to the ignitor wiring harness. Reconnect wires
to ame rollout switches.
11 - Reinstall the gas valve manifold assembly.
Reconnect the gas supply line to the gas valve.
Reinstall the burner box cover.
12 - Reconnect wires to gas valve.
13 - Replace the blower compartment access panel.
14 - Refer to instruction on verifying gas and electrical
connections when re-establishing supplies.
15 - Follow lighting instructions to light and operate
furnace for 5 minutes to ensure that heat exchanger
Power-Up - Number displayed represents by integrated control unit size code (furnace model
and capacity). If three horizontal bars are displayed followed by continuous E203, furnace
control does not recognize unit size code. Configure per the following:
Yes
To enter Program UnitCapacity/Size: push
and hold button next to
7-segment LED display
until solid “P” symbol
appears. Release
button.
IMPORTANT: Field replacement controls may
need to be manually configured to validate
furnace unit size code.
Solid P starts
blinking on
7-Segment LED
P
_
Furnace control in IDLE mode
No heating, cooling or indoor fan
operation)
UNIT SIZE
CODE
0
1
2
3
4
5
6
7
FURNACE MODEL
EL296UH045V36B
EL296UH070V36B
EL296UH090V36C
EL296UH09048C
EL296UH090V60C
EL296UH110V48C
EL296UH110V60C
EL296UH135V60D
−
−
−
No
Turn room thermostat to OFF
UNIT SIZE
CODE
FURNACE MODEL
8
EL296DF0450V36A
9
EL296DF070V48B
11
EL296DF090V60C
U
EL296DF110V60C
Push and hold button. Integrated control will
display unit size code number for each
furnace model for three seconds.
When the correct unit size code is displayed, release
button. Selected code will flash for 10-second period.
During that period, press and hold push button for 5
seconds. Integrated control will store code in
memory and will automatically exit Program UnitCapacity/Size Mode and reset. (If second period
expires or push button is held less than five seconds,
control will automatically exit ProgramCapacity/Size Mode and go into IDLE mode without
storing unit size code. If this happens, programming
function must be repeated).
−
. If
−
−
Verify that the selected unit size code is correct
and stored in non-volatile memory by cycling
the 24 volt power to the furnace control. (At 24
volt power-up of the furnace control, the
7-segment LED will display a unit size code
three horizontal bars display, board does not
recognize unit size code
function must be repeated)
. Programming
FINISHED
Page 65
Page 66
Requirements for Commonwealth of Massachusetts
Modications to NFPA-54, Chapter 10
Revise NFPA-54 section 10.8.3 to add the following
requirements:
For all side wall, horizontally vented, gas-fueled equipment installed in every dwelling, building or structure used
in whole or in part for residential purposes, including those
owned or operated by the Commonwealth and where the
side wall exhaust vent termination is less than seven (7)
feet above the nished grade in the area of the venting, including but not limited to decks and porches, the following
requirements shall be satised:
1 - INSTALLATION OF CARBON MONOXIDE
DETECTORS. At the time of installation of the side
wall, horizontally vented, gas-fueled equipment,
the installing plumber or gastter shall observe that
a hard-wired carbon monoxide detector with an
alarm and battery backup is installed on the oor
level where the gas equipment is to be installed.
In addition, the installing plumber or gastter shall
observe that a battery-operated or hard-wired
carbon monoxide detector with an alarm is installed
on each additional level of the dwelling, building or
structure served by the side wall, horizontally vented,
gas-fueled equipment. It shall be the responsibility
of the property owner to secure the services of
qualied licensed professionals for the installation
of hard-wired carbon monoxide detectors.
a. I n the event that the side wall, horizontally vented, gas-fueled
equipment is installed in a crawl space or an attic, the hardwired carbon monoxide detector with alarm and battery
back-up may be installed on the next adjacent oor level.
b. In the event that the requirements of this subdivision cannot
be met at the time of completion of installation, the owner
shall have a period of thirty (30) days to comply with the
above requirements; provided, however, that during said
thirty (30) day period, a battery-operated carbon monoxide
detector with an alarm shall be installed.
2 - APPROVED CARBON MONOXIDE
DETECTORSach carbon monoxide detector as
required in accordance with the above provisions
shall comply with NFPA 720 and be ANSI/UL 2034
listed and IAS certied.
3 - SIGNAGE. A metal or plastic identication plate
shall be permanently mounted to the exterior of the
building at a minimum height of eight (8) feet above
grade directly in line with the exhaust vent terminal
for the horizontally vented, gas-fueled heating
appliance or equipment. The sign shall read, in print
size no less than one-half (1/2) inch in size, “GAS
VENT DIRECTLY BELOW. KEEP CLEAR OF ALL
OBSTRUCTIONS
4 - INSPECTION. The state or local gas inspector
of the side wall, horizontally vented, gas-fueled
equipment shall not approve the installation unless,
upon inspection, the inspector observes carbon
monoxide detectors and signage installed in
accordance with the provisions of 248 CMR 5.08(2)
(a) 1 through 4.
EXEMPTIONS: The following equipment is exemptfrom 24 CMR 5.08(2)(a) 1 through 4:
1 - The equipment listed in Chapter 10 entitled
“Equipment Not Required to Be Vented” in the most
current edition of NFPA 54 as adopted by the Board;
and
2 - Product Approved side wall, horizontally vented,
gasfueled equipment installed in a room or structure
separate from the dwelling, building or structure
used in whole or in part for residential purposes.
MANUFACTURER REQUIREMENTS - GAS EQUIPMENT VENTING SYSTEM PROVIDED.
When the manufacturer of Product Approved side wall,
horizontally vented, gas-fueled equipment provides a
venting system design or venting system components
with the equipment, the instructions provided by the manufacturer for installation of the equipment and the venting
system shall include:
1 - Detailed instructions for the installation of the venting
system design or the venting system components:
and
2 - A complete parts list for the venting system design
or venting system.
MANUFACTURER REQUIREMENTS GAS EQUIPMENT VENTING SYSTEM NOT PROVIDED.
When the manufacturer of Product Approved side wall,
horizontally vented, gas-fueled equipment does not pro-
vide the parts for venting the ue gases, but identies
“special venting systems,” the following requirements
shall be satised by the manufacturer:
1 - The referenced “special venting system” instructions
shall be included with the appliance or equipment
installation instructions; and
2 - The “special venting systems” shall be Product
Approved by the Board, and the instructions for
that system shall include a parts list and detailed
installation instructions.
A copy of all installation instructions for all Product
Approved side wall, horizontally vented, gas-fueled
equipment, all venting instructions, all parts lists for
venting instructions, and/or all venting design instruc-
tions shall remain with the appliance or equipment at
the completion of the installation.
Page 66
Page 67
FOR THE PROVINCE OF ONTARIO, HORIZONTAL SIDEWALL VENT APPLICATIONS ONLY
For exterior horizontal venting applications, the 2” X 1.5” reducer for 2” venting at the point where the exhaust pipe exits
the structure is not required in direct or nondirect vent applications in the Province of Ontario. In these applications, the
vent should be oriented such that the exhaust plume is unobjectionable. If the installation requires more separation be-
tween the ue gases and the building structure, a reducer may be installed on the exhaust pipe to increase the ue gas
velocity.
ADDENDUM FOR THE PROVINCE OF SASKATCHEWAN
See below for venting in the province of Saskatchewan. Lennox approves the following termination for use in
Saskatchewan Canada.
C
D
B
12”
A
2” (51MM)
Vent Pipe
A − Clearance above grade or
average snow accumulation
B − Horizontal separation between
intake and exhaust
C − Exhaust pipe length
D − Wall support distance from top
of each pipe (intake/exhaust)
NOTE − Flue gas may be acidic and may adversely affect some building materials. If flue gases impinge
on the building materials, a corrosion−resistant shield should be used to protect the wall surface. The
shield should be constructed using wood, sheet metal or other suitable material. All seams, joints, cracks,
etc. in affected area, should be sealed using an appropriate sealant.
12” (305 mm) Min. 12” (305 mm) Min.
6” (152 mm) Min.
24” (610 mm) Max.
Per: Saskatchewan Code of Practice
6” (152 mm) Max.
3” (76MM)
Vent Pipe
6” (152 mm) Min.
24” (610 mm) Max.
6” (152 mm) Max.
Page 67
Loading...
+ hidden pages
You need points to download manuals.
1 point = 1 manual.
You can buy points or you can get point for every manual you upload.