Lennox EL280DF Installation Instructions PDF
Summary of Content for Lennox EL280DF Installation Instructions PDF
Page 1
08/12
50689601
2012 Lennox Industries Inc.
Dallas, Texas, USA
DOWNFLOW
AIR FLOW
INSTALLATION INSTRUCTIONS EL280DF MERIT SERIES GAS FURNACE DOWNFLOW AIR DISCHARGE
50689601 08/2012
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.
THIS MANUAL MUST BE LEFT WITH THE HOMEOWNER FOR FUTURE REFERENCE
WARNING Improper installation, adjustment, alteration, service or maintenance can cause property damage, person- al injury or loss of life. Installation and service must be performed by a licensed professional installer (or equivalent), service agency or the gas supplier.
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 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
EL280DF Gas Furnace 3. . . . . . . . . . . . . . . . . . . . . . . . . .
Shipping and Packing List 3. . . . . . . . . . . . . . . . . . . . . . . .
Safety Information 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Use of Furnace as a Construction Heater 4. . . . . . . . . . .
General 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Combustion, Dilution & Ventilation Air 5. . . . . . . . . . . . . .
Downflow Installation 8. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Setting Equipment 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filters 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Duct System 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Venting 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Piping 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Integrated Control 23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unit StartUp 24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Pressure Adjustment 25. . . . . . . . . . . . . . . . . . . . . . . .
Proper Combustion 26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
High Altitude 26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Other Unit Adjustments 27. . . . . . . . . . . . . . . . . . . . . . . . . .
Heating Sequence of Operation 28. . . . . . . . . . . . . . . . . . .
Service 29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Repair Parts List 30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Start Up and Performance Checklist 31. . . . . . . . . . . . . . .
Litho U.S.A.
Page 2
Unit Dimensions inches (mm)
11/2 (38) Front Panel
GAS PIPING INLET (Either Side)
FLUE OUTLET (Top)
ELECTRICAL INLET (Either Side)
RETURN AIR OPENING
TOP VIEW
A
B
C
D
3/4 (19)
273/4 (705)
191/4 (489)
65/8 (168) Right 71/8 (181) Left
53/8 (137) Right 23/16 (56) Left
33 (838)
AIR FLOW
197/16 (494)
9/16 (14)
B
Supply Air
Supply Air
9/16 (14)
9/16 (14)
31/8 (79)
9/16 (14)
9/16 (14)
197/16 (494)
Model No. A B C D
in. mm in. mm in. mm in. mm
EL280DF070P36A 141/2 368 133/8 340 13 330 43/4 121
EL280DF090P48B 171/2 446 163/8 416 16 406 61/4 159
EL280DF110P60C 21 533 197/8 504 191/2 495 8 203
Page 3
EL280DF Gas Furnace
The EL280DF gas furnace is shipped ready for installation
in the downflow position fueled by natural gas. A conver-
sion kit (ordered separately) is required for use in LP/Pro-
pane gas applications.
Shipping and Packing List
Package 1 of 1 contains
1 Assembled EL280DF unit
1 Bag assembly containing the following:
2 Screws
1 Snap bushing
1 Snap plug
1 Wire tie
1 Vent warning label
1 Owners manual and warranty card
The following items may be ordered separately:
1 Thermostat
1 LP/Propane changeover kit
1 Combustible flooring base
1 High altitude kit
Check equipment for shipping damage. If you find any
damage, immediately contact the last carrier.
Safety Information
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 floor and may be difficult to smell. An LP/propane leak detector should be installed in all LP applications.
WARNING Improper installation, adjustment, alteration, service or maintenance can cause property damage, person- al injury or loss of life. Installation and service must be performed by a licensed professional installer (or equivalent), service agency or the gas supplier.
CAUTION As with any mechanical equipment, personal injury can result from contact with sharp sheet metal edges. Be careful when you handle this equipment.
Certifications
EL280DF units are CSA International certified.
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). The National Fuel Gas Code is
available from the following address:
American National Standards Institute, Inc.
11 West 42nd Street
New York, NY 10036
Clearances
Adequate clearance must be made around the air open-
ings into the vestibule area. In order to ensure proper unit
operation, combustion and ventilation air supply must be
provided according to the current National Fuel Gas Code.
Vent installations must be consistent with the National Fuel
Gas Code venting tables (in this instruction) and applicable
provisions of local building codes.
This furnace is CSA International certified for installation
clearances to combustible material as listed on the unit
nameplate and in the tables in figure 13. Accessibility and
service clearances must take precedence over fire protection
clearances.
Installed Locations
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
floor. 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 haz-
ardous atmosphere, the furnace must be installed accord-
ing to recommended good practice requirements and cur-
rent National Fuel Gas Code.
NOTE Furnace must be adjusted to obtain a temperature
rise within the range(s) specified on the unit nameplate. Fail-
ure to do so may cause erratic limit operation and may also
result in premature heat exchanger failure.
This EL280DF furnace must be installed so that its electri-
cal components are protected from water.
Installed in Combination with a Cooling Coil
When this furnace is used with cooling units, it shall be
installed in parallel with, or on the upstream side of, cooling
units to avoid condensation in the heating compartment.
With a parallel flow arrangement, a damper (or other
means to control the flow of air) must adequately prevent
chilled air from entering the furnace (see figure 1). If the
damper is manually operated, it must be equipped to pre-
vent operation of either the heating or the cooling unit, un-
less it is in the full HEAT or COOL setting.
Page 4
FIGURE 1
AIR HANDLERGAS UNIT
Dampers (open during cooling
operation only)
Dampers (open during heating
operation only)
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 Elec-
tric Code, ANSI/NFPA No. 70. The National Electric Code
(ANSI/NFPA No. 70) is available from the following ad-
dress:
National Fire Protection Association
1 Battery March Park
Quincy, MA 02269
NOTE This furnace is designed for a minimum continu-
ous return air temperature of 60F (16C) or an intermit-
tent operation down to 55F (13C) dry bulb for cases
where a night setback thermostat is used. Return air tem-
perature must not exceed 85F (29C) dry bulb.
The EL280DF furnace may be installed in alcoves, closets,
attics, basements, garages, and utility rooms in the down-
flow position.
This furnace design has not been CSA International
certified for installation in mobile homes, recreational
vehicles, or outdoors.
Use of Furnace as Construction Heater
Lennox does not recommend the use of EL280DF units as
a construction heater during any phase of construction.
Very low return air temperatures, harmful vapors and op-
eration of the unit with clogged or misplaced filters will dam-
age the unit.
EL280DF units may be used for heating of buildings or
structures under construction, if the following conditions
are met:
The vent system must be permanently installed per
these installation instructions.
A room thermostat must control the furnace. The use of
fixed 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 60F (16C) and
80F (27C) must be maintained.
Air filters must be installed in the system and must be
maintained during construction.
Air filters must be replaced upon construction comple-
tion.
The input rate and temperature rise must be set per the
furnace rating plate.
One hundred percent (100%) outdoor air must be pro-
vided for combustion air requirements during construc-
tion. 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
confined space with air from outside.
The furnace heat exchanger, components, duct system,
air filters and evaporator coils must be thoroughly
cleaned following final construction cleanup.
All furnace operating conditions (including ignition, in-
put rate, temperature rise and venting) must be verified
according to these installation instructions.
General
These instructions are intended as a general guide and do
not supersede local codes in any way. Consult authorities
having jurisdiction before installation.
In addition to the requirements outlined previously, the fol-
lowing general recommendations must be considered
when installing a EL280DF furnace:
Place the furnace as close to the center of the air dis-
tribution system as possible. The furnace should also be
located close to the chimney or vent termination point.
Do not install the furnace where drafts might blow direct-
ly into it. This could cause improper combustion and un-
safe operation.
Do not block the furnace combustion air openings 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 insu-
lated space, keep insulation away from the furnace.
NOTE The Commonwealth of Massachusetts stipu-
lates these additional requirements:
Gas furnaces shall be installed by a licensed plumb-
er or fitter only.
The gas cock must be T handle" type.
When a furnace is installed in an attic, the passage-
way to and service area surrounding the equipment
shall be floored.
Page 5
WARNING The State of California has determined that this prod- uct may contain or produce a chemical or chemicals, in very low doses, which may cause serious illness or death. It may also cause cancer, birth defects or re- productive harm.
Combustion, Dilution & Ventilation Air
In the past, there was no problem in bringing in sufficient out-
door air for combustion. Infiltration provided all the air that
was needed. In todays homes, tight construction practices
make it necessary to bring in air from outside for combus-
tion. Take into account that exhaust fans, appliance vents,
chimneys, and fireplaces force additional air that could be
used for combustion out of the house. Unless outside air is
brought into the house for combustion, 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 liv-
ing space creating a potentially dangerous situation.
In the absence of local codes concerning air for combus-
tion and ventilation, use the guidelines and procedures in
this section to install EL280DF furnaces to ensure efficient
and safe operation. You must consider combustion air
needs and requirements for exhaust vents. A portion of this
information has been reprinted with permission from the
National Fuel Gas Code (ANSI-Z223.1). This reprinted ma-
terial is not the complete and official position of the ANSI on
the referenced subject, which is represented only by the
standard in its entirety.
CAUTION Do not install the furnace in a corrosive or contami- nated atmosphere. Meet all combustion and ventila- tion air requirements, as well as all local codes.
CAUTION Insufficient combustion air can cause headaches, nausea, dizziness or asphyxiation. It will also cause excess water in the heat exchanger resulting in rust- ing 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 combus- tion 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
All gas-fired appliances require air for the combustion pro-
cess. If sufficient combustion air is not available, the fur-
nace or other appliances will operate inefficiently and un-
safely. 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 fireplaces, ex-
haust fans, or clothes dryers are used at the same time as
the furnace, much more air is necessary to ensure proper
combustion and to prevent a downdraft. Insufficient 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 contami-
nants may include bleaches, adhesives, detergents, sol-
vents and other contaminants which can corrode furnace
components.
The requirements for providing air for combustion and ven-
tilation depend largely on whether the furnace is installed in
an unconfined or a confined space.
Unconfined Space
An unconfined 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 com-
bined 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 un-
confined, it might be necessary to bring in outdoor air for
combustion if the structure does not provide enough air by
infiltration. 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.
Page 6
Confined Space
A confined space is an area with a volume less than 50 cu-
bic 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 definition 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 contain-
ing 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
confined space such as a closet or small equipment room.
Even a small leak around the base of the unit at the platform
or at the return air duct connection can cause a potentially
dangerous negative pressure condition. Air for combustion
and ventilation can be brought into the confined space either
from inside the building or from outside.
EQUIPMENT IN CONFINED SPACE ALL AIR FROM INSIDE
CHIMNEY OR GAS
VENT
FURNACE WATER HEATER
OPENINGS (To Adjacent
Room)
NOTE Each opening shall have a free area of at least one square inch (645 mm2) per 1,000 Btu (.29 kW) per hour of the total input rat- ing of all equipment in the enclosure, but not less than 100 square inches (64516 mm2).
FIGURE 2
Air from Inside
If the confined space that houses the furnace adjoins a
space categorized as unconfined, 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 gasfired equipment in the confined
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 2.
Air from Outside
If air from outside is brought in for combustion and ventila-
tion, the confined space must have two permanent open-
ings. 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 di-
rectly or by ducts with the outdoors or spaces (crawl or at-
tic) 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 en-
closure. See figures 3 and 4. 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 5.
When ducts are used, they shall be of the same crosssec-
tional 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 cov-
ering is not known for calculating the size opening required,
it may be assumed that wood louvers will have 20 to 25 per-
cent free area and metal louvers and grilles will have 60 to
75 percent free area. Louvers and grilles must be fixed in the
open position or interlocked with the equipment so that they
are opened automatically during equipment operation.
Page 7
EQUIPMENT IN CONFINED SPACE ALL AIR FROM OUTSIDE
(Inlet Air from Crawlspace and Outlet Air to Ventilated Attic)
NOTEThe inlet and outlet air openings shall each have a free area of at least one square inch (645 mm2) per 4,000 Btu (1.17 kW) per hour of the total input rating of all equipment in the enclosure.
VENTILATION LOUVERS (Each end of attic)
OUTLET AIR WATER
HEATER
INLET AIR
CHIMNEY OR GAS VENT
FURNACE
VENTILATION LOUVERS
(For unheated crawl space)
FIGURE 3
EQUIPMENT IN CONFINED SPACE ALL AIR FROM OUTSIDE
(All Air Through Ventilated Attic)
NOTEThe inlet and outlet air openings shall each have a free area of at least one square inch (645 mm2) per 4,000 Btu (1.17 kW) per hour of the total input rating of all equip- ment in the enclosure.
CHIMNEY OR GAS
VENT
WATER HEATER
OUTLET AIR
VENTILATION LOUVERS (Each end of attic)
INLET AIR (Ends 12 in.
above bottom)
FURNACE
FIGURE 4
EQUIPMENT IN CONFINED SPACE
ALL AIR FROM OUTSIDE
OUTLET AIR
INLET AIR
WATER HEATER
CHIMNEY OR GAS
VENT
NOTE Each air duct opening shall have a free area of at least one square inch (645 mm2) per 2,000 Btu (.59 kW) per hour of the total input rating of all equipment in the enclosure. If the equipment room is located against an outside wall and the air openings communicate directly with the outdoors, each open- ing shall have a free area of at least one square inch (645 mm2) per 4,000 Btu (1.17 kW) per hour of the total input rating of all other equipment in the enclosure.
FURNACE
FIGURE 5
Page 8
Downflow Installation
Downflow unit installs in three ways: on noncombustible
flooring, on combustible flooring using a downflow com-
bustible flooring base, or on a reverseflow cooling cabinet.
Do not drag the unit across the floor.
Installation on NonCombustible Flooring (Figure 6)
1 Cut floor opening keeping in mind clearances listed on
unit rating plate. Also keep in mind gas supply connec-
tions, electrical supply, flue and air intake connections
and sufficient installation and servicing clearances.
See table 1 for correct floor opening size.
2 Flange warm air plenum and lower the plenum into the
opening.
3 Set the unit over the plenum and seal the plenum to
the unit.
4 Ensure that the seal is adequate.
FIGURE 6
EL280DF UNIT
SUPPLY AIR PLENUMOPENING
TABLE 1 NONCOMBUSTIBLE FLOOR OPENING SIZE
Cabinet Width Front to Rear Side to Side
in. mm in. mm
A (14.5") 193/4 502 131/4 337
B (17.5") 193/4 502 161/4 413
C (21") 193/4 502 193/4 502
NOTE Floor opening dimensions listed are 1/4 inch (6 mm) larger than the unit opening. See unit dimensions on page 2.
Installation on Combustible Flooring (Figure 7)
1 When unit is installed on a combustible floor, a down-
flow combustible flooring base must be installed be-
tween the furnace and the floor. The base must be or-
dered separately.
See table 2 for opening size to cut in floor.
CAUTION The furnace and downflow combustible flooring base shall not be installed directly on carpeting, tile, or other combustible material other than wood floor- ing.
EL280DF UNIT
SUPPLY AIR PLENUM
DOWNFLOW COMBUSTIBLE
FLOORING BASE
PROPERLY SIZED FLOOR
OPENING
FIGURE 7
TABLE 2 COMBUSTIBLE FLOOR OPENING SIZE
Cabinet Width Front to Rear Side to Side
in. mm in. mm
A (14.5") 22 559 153/4 400
B (17.5") 22 559 183/4 476
C (21") 22 559 223/4 578
2 After opening is cut, set combustible flooring base into
opening.
3 Check sealing strips on combustible flooring base to
make sure they are properly glued and positioned.
4 Lower supply air plenum into downflow combustible
flooring base until plenum flanges seal against the
strips.
NOTE Be careful not to damage sealing strips. Check
for a tight seal.
5 Set the furnace over the plenum.
6 Ensure that the seal between the furnace and plenum
is adequate.
Installation on Cooling Cabinet (Figure 8)
1 Refer to reverseflow coil installation instructions for
correctly sized opening in floor and installation of cabi-
net.
NOTE Downflow combustible flooring kit is not used
2 When cooling cabinet is in place, set and secure the
furnace according to the instructions that are provided
with the cooling coil. Secure the furnace to the cabinet.
3 Seal the cabinet and check for air leaks.
Page 9
EL280DF UNIT
COOLING COIL
PLENUM
FIGURE 8
PROPERLY SIZED FLOOR
OPENING
Return Air Opening Downflow Units
The following steps should be taken when installing ple-
num:
1 Bottom edge of plenum should be flanged with a
hemmed edge (See figure 9).
SECURE FROM
OUTSIDE CABINET
HEMMED EDGE
PLENUM
SEALING STRIP
(Field Provided)
CABINET SIDE PANEL
Side View
FIGURE 9
2 Sealing strip should be used.
3 In all cases, plenum should be secured to top flanges
of furnace with sheet metal screws.
SECURE FROM IN-
SIDE CABINET
HEMMED EDGE
FIBERGLASS
SEALING STRIP
(Field Provided) CABINET SIDE
PANEL
PLENUM
Side View
FIGURE 10
4 In closet installations, it may be impossible to install
sheet metal screws from the outside. In this case,
make plenum with a removable front and install
screws from the inside (See figure 10).
5 Make certain that an adequate seal is made.
Setting Equipment
WARNING Do not install the furnace on its front, back or in the horizontal position. See figure 12. Do not connect the return air ducts to the back of the furnace. Doing so will adversely affect the operation of the safety con- trol devices, which could result in personal injury or death.
Install the EL280DF gas furnace as shipped in the down-
flow position only. Do not install the furnace hori-
zontally.
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,
and installation and service clearances [24 inches (610
mm) at unit front]. The unit must be level.
NOTE Units with 1/2 hp blower motors are equipped with
three flexible legs and one rigid leg. See figure 11. The rigid
leg is equipped with a shipping bolt and a flat white plastic
washer (rather than the rubber mounting grommet used
with a flexible mounting leg). The bolt and washer must
be removed before the furnace is placed into opera-
tion. After the bolt and washer have been removed, the rig-
id leg will not touch the blower housing.
FIGURE 11
RIGID LEG remove shipping bolt and washer
UNITS WITH 1/2 HP BLOWER MOTOR
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 inju- ry or death.
Page 10
FIGURE 12
Front Back Horizontal
Downflow Application
Allow for clearances to combustible materials as indicated
on the unit nameplate. Minimum clearances for closet or al-
cove installations are shown in figure 13.
Downflow Application Installation Clearances
Top
Bottom
Left Side Right Side
Type of Vent Connector
Type C Type B1
Top 1 in. (25 mm) 1 in. (25 mm)
*Front 21/4 in. (57 mm)** 21/4 in. (57 mm)
Back 0 0
Sides 0 0
Vent 6 in. (152 mm) 1 in. (25 mm)
Floor NC NC
*Front clearance in alcove installation must be 24 in. (610 mm). Maintain a minimum of 24 in. (610 mm) for front service access. ** 41/2 in. if a single wall vent pipe is used. Left side requires 3 in. if a single wall vent is used on 14 1/2 in. cab- inets, or 2 in. if a single wall vent is used on 17 1/2 in. cabinets. The furnace may be installed on a combustible wood floor if an optional additive base is installed between the furnace and the combustible floor.
FIGURE 13
WARNING Improper installation of the furnace can result in per- sonal injury or death. Combustion and flue products must never be allowed to enter the return air system or the living space. Use screws and joint tape to seal the return air system to the furnace. In platform installations with bottom return air, the furnace should be sealed airtight to the return air ple- num. 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. Al- low absolutely no sagging, cracks, gaps, etc. The return and supply air duct systems must never be connected to or from other heating devices such as a fireplace or stove, etc. Fire, explosion, carbon monoxide poisoning, personal injury and/or proper- ty damage could result.
Filters
This unit is not equipped with a filter or rack. A fieldpro-
vided highvelocity filter is required for the unit to operate
properly. Table 3 lists recommended filter sizes.
A filter must be in place any time the unit is operating.
TABLE 3
Cabinet Width Return Air Filter Size (inches)
A (141/2") 14 x 25 x 1 (1)
B (171/2") 16 x 25 x 1 (1)
C (21") 20 x 25 x 1 (1)
Page 11
Duct System
Use industry-approved standards (such as those pub-
lished by Air Conditioning Contractors of America or Ameri-
can Society of Heating, Refrigerating and Air Conditioning
Engineers) to size and install the supply and return air duct
system. This will result in a quiet and low-static system that
has uniform air distribution.
NOTE Do not operate the furnace in the heating mode
with an external static pressure that exceeds 0.5 inches
w.c. Higher external static pressures may cause erratic lim-
it operation.
Ensure that you have made a seal between the supply air
plenum and the furnace and between the furnace and the
return air plenum.
Return Air Plenum
Return air must not be drawn from a room where this
furnace, or any other gasfueled appliance (i.e., water
heater), or carbon monoxideproducing device (i.e.,
wood fireplace) 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 pres-
sure, the flue products can be pulled back down the vent
pipe and into the room. This reverse flow of the flue gas
may result in incomplete combustion and the formation
of carbon monoxide gas. This toxic gas might then be dis-
tributed throughout the house by the furnace duct sys-
tem.
Venting
A 4inch diameter flue transition is factory-installed on all models. Modifying or removing the flue transition will cause the unit to operate unsafely and will void the unit certification. The vent connector does not require insula- tion.
The EL280DF series units are classified as fanassisted
Category I furnaces when vertically vented according to
the latest edition of National Fuel Gas Code (NFPA 54 /
ANSI Z223.1). A fanassisted Category I furnace is an ap-
pliance equipped with an integral mechanical means to ei-
ther draw or force combustion products through the com-
bustion chamber and/or heat exchanger.
NOTE Use these instructions as a guide. They do not su-
persede local codes. This furnace must be vented accord-
ing to all local codes, these installation instructions, and the
provided venting tables in these instructions
The venting tables in this manual were extracted from the
National Fuel Gas Code (NFPA 54 / ANSI Z223.1) and are
provided as a guide for proper vent installation. Proper ap-
plication, termination, construction and location of vents
must conform to local codes having jurisdiction. In the ab-
sence of local codes, the NFGC serves as the defining doc-
ument.
Refer to the tables and the venting information contained in
these instructions to properly size and install the venting
system.
IMPORTANT Once the venting system is installed, attach the Dis- connected Vent" warning sticker to a visible area of the plenum near the vent pipe. The warning sticker is provided in the bag assembly. Order kit 66W04 for additional stickers.
WARNING Asphyxiation hazard. The exhaust vent for this fur- nace must be securely connected to the furnace flue transition at all times.
FLUE TRANSITION COLLAR
VENT CONNECTION DISCONNECTED VENT WARNING STICKER
FIGURE 14
Use selfdrilling sheet metal screws or a mechanical fas- tener to firmly secure the vent pipe to the round collar of the flue transition. If selfdrilling screws are used to attach the vent pipe, it is recommended that three be used. Drive one selfdrilling screw through the front and one through each side of the vent pipe and collar. See figure 14.
Install the first vent connector elbow at a minimum of six inches (152 mm) from the furnace vent outlet.
Masonry chimneys used to vent Category I central fur- naces must be either tile-lined or lined with a listed metal lining system or dedicated gas vent. Unlined masonry chimneys are prohibited. See figures 15 and 16 for com- mon venting.
Page 12
FIGURE 15
Common Venting Using TileLined Interior Masonry Chimney and Combined Vent Connector
MINIMUM LENGTH = AS SHORT AS PRACTICAL. FOR MAXIMUM LENGTH SEE NOTE TO LEFT
INTERIOR TILELINED MASONRY CHIMNEY
NOTE the chimney must be properly sized per provided venting tables or lined with listed metal lining system.
PERMANENTLY SEALED FIREPLACE OPENING
VENT CONNECTOR
NOTE Refer to provided venting tables for installations.
FURNACE
OTHER APPLIANCE
Venting Using a Masonry Chimney
The following additional requirements apply when a lined masonry chimney is used to vent this furnace.
A chimney with one or more sides exposed to the outside of the structure is considered to be an exterior chimney.
An exterior masonry chimney that is not tilelined must be
lined with B1 vent or a listed insulated flexible metal vent.
An exterior tilelined chimney that is sealed and capped
may be lined with a listed uninsulated flexible metal vent.
If the existing chimney will not accommodate a listed metal
liner, either the chimney must be rebuilt to accommodate
one of these liners or an alternate approved venting meth-
od must be found.
Insulation for the flexible vent pipe must be an encapsu-
lated fiberglass sleeve recommended by the flexible vent
pipe manufacturer. See figure 16.
FIGURE 16
Common Venting Using MetalLined Masonry Chimney
4 in. (102 mm) minimum
MIN. LENGTH AS SHORT AS PRACTICAL
MAX. LENGTH SEE NOTE
BELOW.
SEALED
PERMANENTLY SEALED FIREPLACE
OPENING
EXTERIOR CHIMNEY WITH
METAL LINER
VENT CONNECTOR
NOTE 1 Refer to the provided venting tables for installations.
OTHER APPLIANCE
FURNACE
5 ft. (1.5 m) minimum
DO NOT insulate the space between the liner and the
chimney wall with puffed mica or any other loose gran-
ular insulating material
IMPORTANT SINGLE appliance venting of a fan-assisted furnace into a tile-lined masonry chimney (interior or outside wall) is PROHIBITED. The chimney must first be lined with either type B1 vent or an insulated single wall flexible vent lining system which has been sized ac- cording to the provided venting tables and the vent pipe manufacturers instructions.
A fanassisted furnace may be commonly vented into an existing lined masonry chimney if the following conditions are met:
The chimney is currently serving at least one drafthood equipped appliance
The vent connectors and chimney are sized according to the provided venting tables.
If type B1 double-wall vent is used inside a chimney, no oth-
er appliance can be vented into the chimney. The outer wall
of type B1 vent pipe must not be exposed to flue products.
A type B1 vent or masonry chimney liner shall terminate
above the roof surface with a listed cap or a listed roof as-
sembly according to the terms of their respective listings
and the vent manufacturers instructions.
When inspection reveals that an existing chimney is not
safe for the intended purpose, it shall be rebuilt to conform
to nationally recognized standards, lined or relined with
suitable materials, or replaced with a gas vent or chimney
suitable for venting EL280DF series units. The chimney
passageway must be checked periodically to ensure that it
is clear and free of obstructions.
Do not install a manual damper, barometric draft regulator,
or flue restrictor between the furnace and the chimney.
Page 13
Never connect a Category I appliance to a chimney that is servicing a solidfuel appliance. If a fireplace chimney flue is used to vent this appliance, the fireplace opening must be permanently sealed.
A type B or listed chimney lining system that passes through an unused masonry chimney flue is not considered to be exposed to the outdoors.
General Venting Requirements
Vent all EL280DF furnaces according to these instructions:
1 Vent diameter recommendations and maximum allow-
able piping runs are found in the provided venting
tables.
2 In no case should the vent or vent connector diameter
be less than the diameter specified in the provided
venting tables.
3 The minimum vent capacity determined by the sizing
tables must be less than the low fire input rating and the
maximum vent capacity must be greater than the high
fire input rating.
4 Single appliance vents If the vertical vent or tile-lined
chimney has a larger diameter or flow area than the
vent connector, use the vertical vent diameter to de-
termine the minimum vent capacity and the vent
connector diameter to determine the maximum vent
capacity. The flow area of the vertical vent, however,
shall not exceed 7 times the flow area of the listed ap-
pliance categorized vent area, drafthood outlet area or
flue collar area unless designed according to approved
engineering methods.
5 Multiple appliance vents The flow area of the largest
section of vertical vent or chimney shall not exceed 7
times the smallest listed appliance categorized vent
area, drafthood outlet area or flue collar area unless de-
signed according to approved engineering methods.
6 The entire length of single wall metal vent connector
shall be readily accessible for inspection, cleaning,
and replacement.
7 Single appliance venting configurations with zero lat-
eral lengths (tables 5 and NO TAG) are assumed to
have no elbows in the vent system. For all other vent
configurations, the vent system is assumed to have
two 90 elbows. For each additional 90 elbow or
equivalent (for example two 45 elbows equal one 90
elbow) beyond two, the maximum capacity listed in the
venting table should be reduced by 10% (0.90 x maxi-
mum listed capacity).
8 The common venting tables (6, 7, NO TAG, and
NO TAG) were generated using a maximum horizontal
vent connector length of 11/2 feet (.46 m) for each inch
(25 mm) of connector diameter as follows:
TABLE 4
Connector Diameter inches (mm)
Maximum Horizontal Connector Length feet (m)
3 (76) 41/2 (1.37)
4 (102) 6 (1.83)
5 (127) 71/2 (2.29)
6 (152) 9 (2.74)
7 (178) 101/2 (3.20)
9 If the common vertical vent is offset, the maximum
common vent capacity listed in the common venting
tables should be reduced by 20%, the equivalent of two
90 elbows (0.80 x maximum common vent capacity).
The horizontal length of the offset shall not exceed
1-1/2 feet (.46 m) for each inch (25 mm) of common
vent diameter.
10 The vent pipe should be as short as possible with the
least number of elbows and angles required to com-
plete the job. Route the vent connector to the vent us-
ing the shortest possible route.
11 A vent connector shall be supported without any dips
or sags and shall slope a minimum of 1/4 inch (6.4 mm)
per linear foot (305 mm) of connector, back toward the
appliance.
12 Vent connectors shall be firmly attached to the furnace
flue collar by selfdrilling screws or other approved
means, except vent connectors of listed type B vent
material which shall be assembled according to the
manufacturers instructions. Joints between sections
of single wall connector piping shall be fastened by
screws or other approved means.
13 When the vent connector used for Category I ap-
pliances must be located in or pass through a crawl-
space or other areas which may be cold, that portion of
the vent connector shall be constructed of listed
double-wall type B vent material or material having
equivalent insulation qualities.
14 All venting pipe passing through floors, walls, and ceil-
ings must be installed with the listed clearance to com-
bustible materials and be fire stopped according to lo-
cal codes. In absence of local codes, refer to NFGC
(Z223.1).
15 No portion of the venting system can extend into, or pass
through any circulation air duct or plenum.
16 Vent connectors serving Category I appliances shall
not be connected to any portion of mechanical draft
systems operating under positive pressure such as
Category III or IV venting systems.
17 If vent connectors are combined prior to entering the
common vent, the maximum common vent capacity
listed in the common venting tables must be reduced by
10%, the equivalent of one 90 elbow (0.90 x maximum
common vent capacity).
18 The common vent diameter must always be at least as
large as the largest vent connector diameter.
Page 14
19 In no case, shall the vent connector be sized more than
two consecutive table size diameters over the size of
the draft hood outlet or flue collar outlet.
20 Do not install a manual damper, barometric draft regu-
lator or flue restrictor between the furnace and the
chimney.
21 When connecting this appliance to an existing dedi-
cated or common venting system, you must inspect the
venting systems general condition and look for signs
of corrosion. The existing vent pipe size must conform
to these instructions and the provided venting tables. If
the existing venting system does not meet these re-
quirements, it must be resized.
TABLE 5
Capacity of Type B DoubleWall Vents with Type B DoubleWall Connectors
Serving a Single Category I Appliance
Height H
(feet)
Lateral L
(feet)
Vent and Connector Diameter D (inches)
3 Inch 4 Inch 5 Inch 6 Inch
Appliance Input Rating in Thousands of Btu Per Hour
MIN MAX MIN MAX MIN MAX MIN MAX
6
0 0 78 0 152 0 251 0 375
2 13 51 18 97 27 157 32 232
4 21 49 30 94 39 153 50 227
6 25 46 36 91 47 149 59 223
8
0 0 84 0 165 0 276 0 415
2 12 57 16 109 25 178 28 263
5 23 53 32 103 42 171 53 255
8 28 49 39 98 51 164 64 247
10
0 0 88 0 175 0 295 0 447
2 12 61 17 118 23 194 26 289
5 23 57 32 113 41 187 52 280
10 30 51 41 104 54 176 67 267
15
0 0 94 0 191 0 327 0 502
2 11 69 15 136 20 226 22 339
5 22 65 30 130 39 219 49 330
10 29 59 40 121 51 206 64 315
15 35 53 48 112 61 195 76 301
20
0 0 97 0 202 0 349 0 540
2 10 75 14 149 18 250 20 377
5 21 71 29 143 38 242 47 367
10 28 64 38 133 50 229 62 351
15 34 58 46 124 59 217 73 337
20 48 52 55 116 69 206 84 322
30
0 0 100 0 213 0 374 0 587
2 9 81 13 166 14 283 18 432
5 21 77 28 160 36 275 45 421
10 27 70 37 150 48 262 59 405
15 33 64 44 141 57 249 70 389
20 56 58 53 132 66 237 80 374
30 NA NA 73 113 88 214 104 346
NOTE Single appliance venting configurations with zero lateral lengths are assumed to have no elbows in the vent system. For all other vent configurations, the vent system is assumed to have two 90 elbows. For each additional 90 elbow or equivalent (for example two 45 elbows equal one 90 elbow) beyond two, the maximum capacity listed in the venting table should be reduced by 10 percent (0.90 x maxi- mum listed capacity).
Page 15
TABLE 6
Vent Connector Capacity
Type B DoubleWall Vents with Type B DoubleWall Connectors
Serving Two or More Category I Appliances
Vent Height
H (feet)
Connector Rise
R (feet)
Vent and Connector Diameter D (inches)
3 Inch 4 Inch 5 Inch 6 Inch
Appliance Input Rating in Thousands of Btu Per Hour
MIN MAX MIN MAX MIN MAX MIN MAX
6
1 22 37 35 66 46 106 58 164
2 23 41 37 75 48 121 60 183
3 24 44 38 81 49 132 62 199
8
1 22 40 35 72 49 114 64 176
2 23 44 36 80 51 128 66 195
3 24 47 37 87 53 139 67 210
10
1 22 43 34 78 49 123 65 189
2 23 47 36 86 51 136 67 206
3 24 50 37 92 52 146 69 220
15
1 21 50 33 89 47 142 64 220
2 22 53 35 96 49 153 66 235
3 24 55 36 102 51 163 68 248
20
1 21 54 33 99 46 157 62 246
2 22 57 34 105 48 167 64 259
3 23 60 35 110 50 176 66 271
30
1 20 62 31 113 45 181 60 288
2 21 64 33 118 47 190 62 299
3 22 66 34 123 48 198 64 309
TABLE 7
Common Vent Capacity
Type B DoubleWall Vents with Type B DoubleWall Connectors
Serving Two or More Category I Appliances
Vent Height
H (feet)
Common Vent Diameter D (inches)
4 Inch 5 Inch 6 Inch 7 Inch
Appliance Input Rating in Thousands of Btu Per Hour
FAN + FAN FAN + NAT FAN + FAN FAN + NAT FAN + FAN FAN + NAT FAN + FAN FAN + NAT
6 92 81 140 116 204 161 309 248
8 101 90 155 129 224 178 339 275
10 110 97 169 141 243 194 367 299
15 125 112 195 164 283 228 427 352
20 136 123 215 183 314 255 475 394
30 152 138 244 210 361 297 547 459
Page 16
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 ap-
pliances, the venting system is likely to be too large to
properly vent the remaining attached appliances.
Conduct the following test while each appliance is operat-
ing and the other appliances (which are not operating) re-
main 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 re-
quirements 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 mon- oxide poisoning or death. The following steps shall be followed for each ap- pliance connected to the venting system being placed into operation, while all other appliances connected to the venting system are not in operation:
1 Seal any unused openings in the common venting sys-
tem.
2 Inspect the venting system for proper size and horizontal
pitch. Determine that there is no blockage, restriction,
leakage, corrosion, or other deficiencies which could
cause an unsafe condition.
3 Close all building doors and windows and all doors be-
tween the space in which the appliances remaining
connected to the common venting system are located
and other spaces of the building. Turn on clothes dry-
ers 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 oper-
ate at maximum speed. Do not operate a summer ex-
haust fan. Close fireplace 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 flue gases at the draft hood relief opening.
Use the flame of a match or candle, or smoke from a
cigarette, cigar, or pipe.
6 After determining that each appliance connected to the
common venting system is venting properly, (step 3)
return all doors, widows, exhaust fans, fireplace damp-
ers, and any other gasburning appliances to their pre-
vious mode of operation.
7 If a venting problem is found during any of the preced-
ing tests, the common venting system must be modi-
fied 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 stan-
dards of the National Fuel Gas Code ANSI Z223.1.
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.
CAUTION If a flexible 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 flexible connector can then be added between the black iron pipe and the gas supply line.
Gas Supply
1 This unit is shipped standard for left or right side instal-
lation of gas piping. Connect the gas supply to the pip-
ing assembly.
2 When connecting the gas supply piping, consider fac-
tors such as length of run, number of fittings, and fur-
nace rating to avoid excessive pressure drop. Table 8
lists recommended pipe sizes for typical applications.
3 The gas piping must not run in or through air ducts,
clothes chutes, gas vents or chimneys, dumb waiters,
or elevator shafts.
4 The piping should be sloped 1/4 inch (6.4 mm) per 15
feet (4.57 m) upward toward the meter from the fur-
nace. The piping must be supported at proper intervals
[every 8 to 10 feet (2.44 to 3.01 m)] with suitable hang-
ers or straps. Install a drip leg inside vertical pipe runs
to the unit.
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 NO TAG.
6 In some localities, codes may require the installation of
a manual main shut-off valve and union (furnished by
the installer) external to the unit. The union must be of
the ground joint type.
IMPORTANT Compounds used on threaded joints of gas piping must be resistant to the actions of liquified petro- leum gases.
NOTE If emergency shutoff is necessary, shut off the main
manual gas valve and disconnect main power to the fur-
nace. The installer should properly label these devices.
Page 17
TABLE 8
Gas Pipe Capacity ft3/hr (m3/hr)
Nominal Iron Pipe
Size inches (mm)
Internal Diameter inches (mm)
Length of Pipe feet (m)
10 (3.048)
20 (6.096)
30 (9.144)
40 (12.192)
50 (15.240)
60 (18.288)
70 (21.336)
80 (24.384)
90 (27.432)
100 (30.480)
1/2 (12.7)
.622 (17.799)
172 (4.87)
118 (3.34)
95 (2.69)
81 (2.29)
72 (2.03)
65 (1.84)
60 (1.69)
56 (1.58)
52 (1.47)
50 (1.42)
3/4 (19.05)
.824 (20.930)
360 (10.19)
247 (7.00)
199 (5.63)
170 (4.81)
151 (4.28)
137 (3.87)
126 (3.56)
117 (3.31)
110 (3.11)
104 (2.94)
1 (25.4)
1.049 (26.645)
678 (19.19)
466 (13.19)
374 (10.59)
320 (9.06)
284 (8.04)
257 (7.27)
237 (6.71)
220 (6.23)
207 (5.86)
195 (5.52)
11/4 (31.75)
1.380 (35.052)
1350 (38.22)
957 (27.09)
768 (22.25)
657 (18.60)
583 (16.50)
528 (14.95)
486 (13.76)
452 (12.79)
424 (12.00)
400 (11.33)
11/2 (38.1)
1.610 (40.894)
2090 (59.18)
1430 (40.49)
1150 (32.56)
985 (27.89)
873 (24.72)
791 (22.39)
728 (20.61)
677 (19.17)
635 (17.98)
600 (17.00)
2 (50.8)
2.067 (52.502)
4020 (113.83)
2760 (78.15)
2220 (62.86)
1900 (53.80)
1680 (47.57)
1520 (43.04)
1400 (39.64)
1300 (36.81)
1220 (34.55)
1160 (32.844)
21/2 (63.5)
2.469 (67.713)
6400 (181.22)
4400 (124.59)
3530 (99.95)
3020 (85.51)
2680 (75.88)
2480 (70.22)
2230 (63.14)
2080 (58.89)
1950 (55.22)
1840 (52.10)
3 (76.2)
3.068 (77.927)
11300 (319.98)
7780 (220.30)
6250 (176.98)
5350 (151.49)
4740 (134.22)
4290 (121.47)
3950 (111.85)
3670 (103.92)
3450 (97.69)
3260 (92.31)
NOTE Capacity given in cubic feet (m3 ) of gas per hour and based on 0.60 specific gravity gas.
GROUND JOINT UNION
AUTOMATIC GAS VALVE (with manual
shutoff valve)
FIELD PROVIDED
AND INSTALLED
GROUND JOINT UNION
Left Side Piping (Standard)
Right Side Piping (Alternate)
AUTOMATIC GAS VALVE (with manual
shutoff valve)
DRIP LEG
DRIP LEG
MANUAL MAIN SHUTOFF
VALVE
MANUAL MAIN SHUTOFF
VALVE
NOTE BLACK IRON PIPE ONLY TO BE ROUTED INSIDE OF CABINET
FIGURE 17
Page 18
Leak Check
After gas piping is completed, carefully check all piping
connections (factory and fieldinstalled) for gas leaks. Use
a leak detecting solution or other preferred means.
NOTE If emergency shutoff is necessary, shut off the main
manual gas valve and disconnect the main power to the
furnace. The installer should properly label these devices.
CAUTION Some soaps used for leak detection are corrosive to certain metals. Carefully rinse piping thoroughly af- ter leak test has been completed. Do not use matches, candles, flame or other sources of ignition to check for gas leaks.
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.).
IMPORTANT When testing pressure of gas lines, gas valve must be disconnected and isolated. See figure 18. Gas valves can be damaged if subjected to pressures greater than 1/2 psig (3.48 kPa, 14 inches w.c.).
MANUAL MAIN SHUTOFF VALVE WILL NOT HOLD NORMAL TEST
PRESSURE
CAP
ISOLATE GAS VALVE
FURNACE
FIGURE 18
1/8 NPT PLUG
Electrical
ELECTROSTATIC DISCHARGE (ESD)
Precautions and Procedures
CAUTION Electrostatic discharge can affect elec- tronic components. Take precautions to neutralize electrostatic charge by touching your hand and tools to metal prior to handling the control.
The unit is equipped with a field makeup box on the left
hand side of the cabinet. The makeup box may be moved
to the right side of the furnace to facilitate installation. If the
makeup box is moved to the right hand side, clip the wire
ties that bundle the wires together. Secure the excess wire
to the existing harness to protect it from damage.
INTERIOR MAKEUP BOX INSTALLATION (Right Side)
FIGURE 19
MAKEUP BOX
Cut the two wire ties to extend power wires for right side only
Refer to figure 20 for schematic wiring diagram and trou-
bleshooting and table 9 for field wiring.
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.
NOTE Unit nameplate states maximum current draw.
Maximum overcurrent protection allowed is 15 AMP.
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, check to make sure the
wires will be long enough for servicing at a later date. Make
sure that thermostat wire is long enough to facilitate future
removal of blower for service.
Complete the wiring connections to the equipment. Use
18gauge 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 Na-
tional Electric Code (ANSI/NFPA No. 70). A green ground
wire is provided in the field makeup box.
NOTE The EL280DF furnace contains electronic compo-
nents that are polarity sensitive. Make sure that the furnace
is wired correctly and is properly grounded.
Accessory Terminals
One line voltage EAC" 1/4" spade terminal is provided on
the furnace integrated control. See figure 21 for integrated
control configuration. This terminal is energized when the
indoor blower is operating. Any accessory rated up to one
amp can be connected to this terminal with the neutral leg
Page 19
of the circuit being connected to one of the provided neutral
terminals. If an accessory rated at greater than one amp is
connected to this terminal, it is necessary to use an exter-
nal relay.
One line voltage HUM" 1/4" spade terminnal is provided on
the furnace integrated control. See figure 21 for integrated
control configuration. This terminal is energized in the
heating mode when the combustion air inducer is operat-
ing. Any humidifier rated up to one amp can be connected
to this terminal with the neutral leg of the circuit being con-
nected to one of the provided neutral terminals. If a humidi-
fier rated at greater than one amp is connected to this termi-
nal, it is necessary to use an external relay relay.
One 24V "H" 1/4" spade terminal is provided on the furnace
integrated control. See figure 21 for integrated control con-
figuration. The terminal is energized in the heating mode
when the combustion air inducer is operating and the pres-
sure switch is closed. Any humidifier rated up to 0.5 amp
can be connected to this terminal with the ground leg of the
circuit connected to ground or the "C" terminal.
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 + 10% (Range: 108
volts to 132 volts).
The furnace operates at 60 Hz + 5% (Range: 57 Hz to 63 Hz).
The furnace integrated control requires both proper polarity and proper ground. Both polarity and proper grounding should be checked before attempting to op- erate the furnace on either permanent or temporary power.
Generator should have a wave form distortion of less than 5% total harmonic distortion (THC).
Thermostat
Install the room thermostat according to the instructions
provided with the thermostat. See table 9 for thermostat
designations. If the furnace is being matched with a heat
pump, refer to the FM21 installation instruction or appropri-
ate dual fuel thermostat instructions.
Indoor Blower Speeds
1 When the thermostat is set to FAN ON," the indoor blower will run continuously on the low heat speed when there is no cooling or heating demand.
2 When the EL280DF is operating in the highfire or low fire heating mode, the indoor blower will run on the cor- responding heating speed.
3 When the EL280DF is operating in the low cool or the high cool cooling mode, the indoor blower will run on the corresponding cooling speed.
Page 20
TABLE 9
Field Wiring Applications
Thermostat
DIP Switch Settings and OnBoard Links (See figure 21)
Wiring Connections DIP Switch 1
W915 TwoStage
Cooling W951
Heat Pumps
1 Heat / 1 Cool
NOTE Use DIP switch 2 to set sec- ondstage heat ON delay. OFF10 minutes. ON15 minutes.
ON Intact Intact S1 TSTAT
CONTROL TERM. STRIP
OUTDOOR UNIT
1 Heat / 2 Cool
NOTE Use DIP switch 2 to set sec- ondstage heat ON delay. OFF10 minutes. ON15 minutes.
ON Cut Intact S1 TSTAT
CONTROL TERM. STRIP
OUTDOOR UNIT
Page 21
TABLE 9
Field Wiring Applications (Continued)
Thermostat
DIP Switch Settings and OnBoard Links (See figure 21)
Wiring Connections DIP Switch 1
W915 TwoStage
Cooling W951
Heat Pumps
2 Heat / 2 Cool OFF Cut Intact S1 TSTAT
CONTROL TERM. STRIP
OUTDOOR UNIT
2 Heat / 1 Cool OFF Intact Intact S1 TSTAT
CONTROL TERM. STRIP
OUTDOOR UNIT
Page 22
FIGURE 20
EL280DF Schematic Wiring Diagram
Page 23
Integrated Control
FIGURE 21
TWOSTAGE INTEGRATED CONTROL
THERMOSTAT CONNECTIONS (TB1)
1/4" QUICK CONNECT TERMINALS
DIP SWITCH FUNCTIONS
DIP SWITCHES
DIAGNOSTIC LEDs
ONBOARD LINKS 1= ERROR CODE RECALL
H= 24V HUMIDIFIER OUTPUT L= LENNOX SYSTEM OPERATION MONITOR
SENSE = 120 VAC OUTPUT TO FLAME SENSER
NEUTRALS= 120 VAC NEUTRAL
PARK = DEAD TERMINAL FOR UNUSED BLOWER LEAD HEAT LOW = 120 VAC OUTPUT TO CIRC BLWR LOW HT SPEED HEAT HIGH/ COOL LOW = 120 VAC OUTPUT TO CIRC BLWR
HIGH HEAT AND LOW COOL SPEED COOL HIGH = 120 VAC OUTPUT TO CIRC BLWR HIGH COOL SPEED
DIP SWITCH(ES) FUNCTION
1 2 Stage Tstat Selects t/stat type (single or twostage) 2 2nd Stage Delay Second stage ON delay (singlestage tstat)
3 & 4 Heat Off Delay Heating fan OFF delay
5 Cool Off Delay Cooling fan OFF delay
W915
W951
EL280DF units are equipped with a twostage integrated control. This control manages ignition timing and fan off delays 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 con- tinuous thermostat demand for heat, the watchguard will break and remake thermostat demand to the furnace and automatically reset the control to relight the furnace.
DIP Switch Settings Switch 1 Thermostat Selection This unit may be used
with either a singlestage or twostage thermostat. The
thermostat selection is made using a DIP switch which
must be properly positioned for the particular application.
The DIP switch is factorypositioned for use with a two
stage thermostat. If a singlestage thermostat is to be used,
the DIP switch must be repositioned.
Select OFF" for twostage heating operation con- trolled by a twostage heating thermostat (factory set- ting);
b Select ON" for twostage heating operation con- trolled by a singlestage heating thermostat. This set- ting provides a timed delay before secondstage heat is initiated.
Switch 2 Second Stage Delay (Used with Single
Stage Thermostat Only) This switch is used to deter-
mine the second stage on delay when a singlestage ther-
mostat is being used. The switch is factoryset in the OFF
position, which provides a 10minute delay before second
stage heat is initiated. If the switch is toggled to the ON
position, it will provide a 15minute delay before second
stage heat is initiated. This switch is only activated when
the thermostat selector jumper is positioned for SINGLE
stage thermostat use.
Switches 3 and 4 Heating BlowerOff Delay The
heating bloweron delay of 45 seconds is not adjustable.
The heating bloweroff delay (time that the blower operates
after the heating demand has been satisfied) can be ad-
justed by moving switches 3 and 4 on the integrated con-
trol. The unit is shipped from the factory with a heating
bloweroff delay of 90 seconds. The heating blower off
delay affects comfort and is adjustable to satisfy individual
applications. Adjust the blower off delay to achieve a sup-
ply air temperature between 90 and 110F at the exact
moment that the blower is deenergized. Longer off delay
Page 24
settings provide lower supply air temperatures; shorter set-
tings provide higher supply air temperatures.Table 10 pro-
vides the blower off timings that will result from different
switch settings.
TABLE 10 Heating BlowerOff Delay Switch Settings
Blower Off Delay (Seconds)
Switch 3 Switch 4
60 Off On
90 (factory setting) Off Off
120 On Off
180 On On
Switch 5 Cooling BlowerOff Delay The cooling
bloweroff delay (time that the blower operates after the
cooling demand has been satisfied) can be adjusted by
moving switch 5 on the integrated control. The switch is fac-
toryset in the OFF position, which provides a cooling blow-
eroff delay of 45 seconds. If the switch is toggled to the ON
position, it will provide a 2second cooling bloweroff delay
OnBoard Link W951 Onboard link W951 is a clippable connection between ter- minals 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 dual fuel use. If the link is left intact, terminal O" will remain ener- gized eliminating the HEAT MODE in the heat pump.
OnBoard Link W915 Onboard link W915 is a clippable connection between ter- minals Y1 and Y2 on the integrated control. W915 must be cut if twostage cooling will be used. If the link is not cut the outdoor unit will operate in secondstage cooling only.
Unit StartUp
FOR YOUR SAFETY READ BEFORE LIGHTING
WARNING Do not use this furnace if any part has been under- water. A flooddamaged furnace is extremely dan- gerous. Attempts to use the furnace can result in fire or explosion. Immediately call a qualified ser- vice 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 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 mainte- nance, turn the electrical power to unit OFF at dis- connect switch.
BEFORE LIGHTING smell all around the appliance area for
gas. Be sure to smell next to the floor because some gas is
heavier than air and will settle on the floor.
The gas valve on the EL280DF unit will be equipped with a
gas control switch. Use only your hand to move the switch.
Never use tools. If the switch will not turn or if the control
switch will not move by hand, do not try to repair it.
Placing the furnace into operation:
EL280DF units are equipped with an automatic ignition
system. Do not attempt to manually light burners on these
furnaces. 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 units with an automatic
ignition system.
WARNING If you do not follow these instructions exactly, a fire or explosion may result causing property damage, personal injury or death.
Gas Valve Operation (Figure 22)
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 upper access panel.
6 Move switch on gas valve to OFF. Do not force. See
figure 22.
7 Wait five minutes to clear out any gas. If you then smell
gas, STOP! Immediately call your gas supplier from a
neighbors phone. Follow the gas suppliers instruc-
tions. If you do not smell gas go to next step.
Page 25
FIGURE 22
GAS VALVE SHOWN IN ON POSITION
INLET PRESSURE POST HIGH FIRE ADJUSTMENT
SCREW (under cap)
MANIFOLD PRESSURE TAP
8 Move switch on gas valve to ON. Do not force. See fig-
ure 22.
9 Replace the upper 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 techni-
cian 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 upper access panel.
4 Move switch on gas valve to OFF. Do not force.
5 Replace the upper 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 circuit breaker?
5 Is the filter dirty or plugged? Dirty or plugged filters 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 lock out? If the unit locks out again, call the service technician to inspect the unit for blockages.
10 Is pressure switch closed? Obstructed flue will cause unit to shut off at pressure switch. Check flue and outlet for blockages.
11 Are flame rollout switches tripped? If flame rollout switches are tripped, call the service technician for in- spection.
Gas Pressure Adjustment
Gas Flow (Approximate)
TABLE 11
GAS METER CLOCKING CHART
EL280DF Unit
Seconds for One Revolution
Natural LP
1 cu ft Dial
2 cu ft Dial
1 cu ft Dial
2 cu ft DIAL
045 80 160 200 400
070 55 110 136 272
090 41 82 102 204
110 33 66 82 164
135 27 54 68 136
Natural1000 btu/cu ft LP2500 btu/cu ft
Furnace should operate at least 5 minutes before check-
ing gas flow. Determine time in seconds for two revolu-
tions of gas through the meter. (Two revolutions assures a
more accurate time.) Divide by two and compare to time
in table 11. If manifold pressure matches table 13 and rate
is incorrect, check gas orifices for proper size and restric-
tion. 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 22. 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 13
for supply line pressure.
Manifold Pressure
NOTE Pressure test adapter kit (10L34) is available from
Lennox to facilitate manifold pressure measurement.
1 Connect test gauge to manifold pressure tap (figure
22) gas valve.
2 Ignite unit on high fire and let run for 5 minutes to allow
for steady state conditions.
3 After allowing unit to stabilize for 5 minutes, record
manifold pressure and compare to value given in table
13.
4 If necessary, make adjustments. Figure 22 shows
location of high fire adjustment screw.
5 If an adjustment is made on high fire, recheck man-
ifold pressure on low fire. Do not adjust low fire man-
ifold pressure. If low fire manifold pressure is more
than 1/2" above or below value specified in table 13,
replace valve.
NOTE Shut unit off and remove manometer as soon as an
accurate reading has been obtained. Take care to remove
barbed fitting and replace threaded plug.
Page 26
Proper Combustion
Furnace should operate minimum 15 minutes with correct
manifold pressure and gas flow rate before checking com-
bustion. Table 12 shows acceptable combustion for ALL
EL280DF models. The maximum carbon monoxide
reading should not exceed 50 ppm
TABLE 12
Firing Rate CO2% For Nat CO2% For L.P.
High Fire 6.8 7.4 7.5 9.0
Low Fire 4.2 5.7 5.0 6.0
High Altitude
The manifold pressure may require adjustment and com-
bustion air pressure switch may need replacing to ensure
proper combustion at higher altitudes. Refer to table 13 for
manifold pressure and table 14 for pressure switch change
and gas conversion kits.
IMPORTANT For safety, shut unit off and remove manometer as soon as an accurate reading has been obtained. Take care to replace pressure tap plug.
TABLE 13
Manifold Pressure Settings at all Altitudes
Unit Input
Gas
Manifold Pressure in.wg.
04500 ft.
Manifold Pressure in.wg. 45017500 ft.1
Manifold Pressure in.wg. 7501 10,000 ft.2
Supply Line Pressure in. w.g.
Low Fire High Fire Low Fire High Fire Low Fire High Fire Min Max
070 Natural 1.7 3.5 1.5 3.2 1.7 3.5 4.5 13.0
LP/propane3 4.9 10.0 4.9 10.0 4.9 10.0 11.0 13.0
090 Natural 1.7 3.5 1.5 3.0 1.7 3.5 4.5 13.0
LP/propane3 4.9 10.0 4.9 10.0 4.9 10.0 11.0 13.0
110 Natural 1.7 3.5 1.5 3.2 1.7 3.5 4.5 13.0
LP/propane3 4.9 10.0 4.9 10.0 4.9 10.0 11.0 13.0
1 This is the only permissible derate for these units. 2 Natural gas high altitude orifice kit required. 3 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.
NOTE Units may be installed at altitudes up to 4500 ft. above sea level without modifications.
TABLE 14
Pressure Switch and Gas Conversion Kits at all Altitudes
Unit Input
High Altitude Pressure Switch Kit High Altitude
Natural Gas Kit LP/Propane Gas Kit
LP/Propane to Natural Kit
0 4500 ft. 4501 7500 ft. 7501 10,000 ft. 7501 10,000 ft. 0 7500 ft 7501 10,000 ft. 0 7500 ft.Min
070
No Change No Change
73W36
73W37 77W07 77W11 77W09090 73W36
110 73W35
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.
Page 27
Other Unit Adjustments
Primary and Secondary Limits
The primary limit is located on the heating compartment
vestibule panel. The secondary limits (if equipped) are lo-
cated in the blower compartment, attached to the back side
of the blower. These auto reset limits are factoryset and re-
quire no adjustment.
Flame Rollout Switches
These manually reset switches are located on the burner
box.
Pressure Switch
The pressure switch is located in the heating compartment
adjacent to the combustion air inducer. The switch checks
for proper combustion air inducer operation before allow-
ing ignition trial. The switch is factoryset and requires no
adjustment.
Temperature Rise
After the furnace has been started, and supply and return
air temperatures have been allowed to stabilize, check the
temperature rise. If necessary, adjust the blower speed to
maintain the temperature rise within the range shown on
the unit nameplate. Increase the blower speed to decrease
the temperature. Decrease the blower speed to increase
the temperature rise. Failure to adjust the temperature rise
may cause erratic limit operation.
Fan Control
The fanon time of 30 seconds is not adjustable. The heat
fanoff delay (amount of time that the blower operates after
the heat demand has been satisfied) may be adjusted by
changing DIP switches 3 and 4. See figure 23 and table 10.
The unit is shipped with a factory fanoff delay setting of 90
seconds. The fanoff delay affects comfort and is adjust-
able to satisfy individual applications. Adjust the fanoff
delay to achieve a supply air temperature between 90 and
110F at the moment that the blower is deenergized. Lon-
ger off delay settings provide lower return air temperatures;
shorter settings provide higher return air temperatures.
See figure 23.
HEAT FAN-OFF TIME IN SECONDS
FIGURE 23
60sec. 90sec.
120sec. 180sec.
1 2 3 4 5 1 2 3 4 5
1 2 3 4 5 1 2 3 4 5
To adjust fanoff timing, flip dip switch to desired setting.
Input Voltage Requirements The circuit is designed to be operated with AC voltage. A voltage of 12 to 33VAC is required to energize the motor. Expected current draw will be less than 20mA.
Blower Speeds
Follow the steps below to change the blower speeds.
1 Turn off electrical power to furnace.
2 Remove blower access panel.
3 Disconnect existing speed tap at integrated control
speed terminal.
NOTE Termination of any unused motor leads must be insulated.
4 Place unused blower speed tap on integrated control
PARK" terminal or insulate.
5 Refer to blower speed selection chart on unit wiring dia-
gram for desired heating or cooling speed. See Blower
performance data beginning on the next page.
6 Connect selected speed tap at integrated control
speed terminal.
7 Resecure blower access panel.
8 Turn on electrical power to furnace.
9 Recheck temperature rise.
Electronic Ignition
The integrated control has an added feature of an internal Watchguard control. The feature serves as an automatic re- set device for integrated control lockout caused by ignition failure. This type of lockout is usually due to low gas line pressure. After one hour of continuous thermostat demand for heat, the Watchguard will break and remake thermostat demand to the furnace and automatically reset the inte- grated control to begin the ignition sequence.
Page 28
Heating Sequence of Operation
When there is a call for heat, the integrated control runs a
self check. The control checks for S10 primary limit, S21
secondary limit (s) and S47 rollout switch normally closed
contacts. The control also checks for S102 high heat and
S128 low heat prove switch normally open contacts. Once
self check is complete and all safety switches are opera-
tional, heat call can continue.
TwoStage Thermostat, Two Stage Heat. Dip Switch set at TWO".
1 SureLight control energizes combustion air inducer B6
on low heat speed. Combustion air inducer runs until
S128 low heat prove switch contacts close (switch
must close within 2 1/2 minutes or control goes into
Watchguard Pressure Switch mode. High heat prove
switch S102 may also close). A 15 second prepurge
follows once S128 closes.
NOTE If the low fire pressure switch does not close the
combustion air inducer will switch to high fire. After a 15
second prepurge the high fire pressure switch will close
and the unit will begin operation on high fire. After 10 to 20
seconds of high fire operation the unit will switch to low fire.
NOTE If the furnace is operating on continuous fan mode
(terminal R" and G" are energized), the combustion air in-
ducer will energize on high speed, the gas valve will ener-
gize on secondstage heat and the furnace will operate on
high fire. Furnace will stay on high fire for 60 seconds then
switch to low fire.
2 SureLight control begins 20 second ignitor warm up
period.
3 Gas valve opens on first stage for a 4 second trial for
ignition. Ignitor stays energized during the trial or until
flame sensed.
4 Flame is sensed, gas valve remains on first stage heat,
ignitor deenergizes.
5 After 30 second delay, indoor blower B3 is energized
on low heat speed.
The furnace will stay in this mode until first stage de-
mand is satisfied OR a second stage heat demand is
initiated.
6 Second stage heat demand initiated. A 30 second sec-
ond stage recognition period begins.
7 The combustion air inducer ramps up to high heat
speed.
8 S102 high heat prove switch closes and the gas valve
energizes second stage heat.
9 B3 indoor blower switches to high heat speed.
SingleStage Thermostat, Two Stage Heat. Dip Switch set at SINGLE"
1 SureLight control energizes combustion air inducer B6
on low heat speed. Combustion air inducer runs until
S128 low heat prove switch contacts close (switch
must close within 2 1/2 minutes or control goes into
Watchguard Pressure Switch mode. High heat prove
switch S102 may also close). A 15 second prepurge
follows once S128 closes.
NOTE If the low fire pressure switch does not close the
combustion air inducer will switch to high fire. After a 15
second prepurge the high fire pressure switch will close
and the unit will begin operation on high fire. After 10 to 20
seconds of high fire operation the unit will switch to low fire.
NOTE If the furnace is operating on continuous fan mode
(terminal R" and G" are energized), the combustion air in-
ducer will energize on high speed, the gas valve will ener-
gize on secondstage heat and the furnace will operate on
high fire. Furnace will stay on high fire for 60 seconds then
switch to low fire.
2 SureLight control begins 20 second ignitor warm up
period.
3 Gas valve opens on first stage for a 4 second trial for
ignition. Ignitor stays energized during the trial or until
flame sensed.
4 Flame is sensed, gas valve remains on first stage heat,
ignitor deenergizes.
5 After 30 second delay, indoor blower B3 is energized
on low heat speed.
6 A 10 minute (factory set) or 15 minute (field set) second
stage heat delay period begins.
7 After the delay the combustion air inducer ramps up to
high heat speed.
8 S102 high heat prove switch closes and the gas valve
energizes second stage heat.
9 B3 indoor blower switches to high heat speed.
Page 29
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 opera- tion, serious injury, death, or property damage. Before servicing, disconnect all electrical power to furnace. When servicing controls, label all wires prior to dis- connecting. Take care to reconnect wires correctly. Verify proper operation after servicing.
At the beginning of each heating season, a licensed profes-
sional technician (or equivalent) should check the system
as follows:
Blower
Check the blower wheel for debris and clean if necessary.
The blower motors are prelubricated for extended bearing
life. No further lubrication is needed.
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 inju- ry or death.
Filters
All EL280DF filters are installed external to the unit. Filters
should be inspected monthly. Clean or replace the filters
when necessary to ensure that the furnace operates prop-
erly. Replacement filters must be rated for high velocity air-
flow. Table 3 lists recommended filter sizes.
Flue And Chimney
1 Check flue pipe, chimney and all connections for tight- ness and to make sure there is no blockage.
2 Check unit for proper draft.
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 ampdraw on the blower motor with blower ac- cess panel in place. Unit Nameplate__________Actual__________
Cleaning the Burners
NOTE Use papers or protective covering in front of the fur-
nace during cleaning.
1 Turn off both electrical and gas power supplies to fur- nace.
3 Label the wires from gas valve, rollout switches, prima-
ry limit switch and makeup box then disconnect them.
4 Disconnect gas supply piping. Remove the four screws
securing the burner manifold assembly to the vestibule
panel and remove the assembly from the unit.
5 Remove 4 screws securing burner box and remove
burner box.
6 To clean burners, run a vacuum cleaner with a soft brush
attachment over the face of burners. Visually inspect in-
side the burners and crossovers for any blockage
caused by foreign matter. Remove any blockage. Figure
24 shows burner detail.
7 Reinstall burner box, manifold assembly and burner box
cover.
8 Reconnect all wires.
9 Reconnect gas supply piping.
10 Turn on power and gas supply to unit.
11 Set thermostat and check for proper operation.
12 Check all piping connections, factory and field, for gas
leaks. Use a leak detecting solution or other preferred
means.
CAUTION Some soaps used for leak detection are corrosive to certain metals. Carefully rinse piping thoroughly af- ter leak test has been completed. Do not use matches, candles, flame or other sources of ignition to check for gas leaks.
13 If a leak is detected, shut gas and electricity off and
repair leak.
14 Repeat steps 12 and 13 until no leaks are detected.
15 Replace access panel.
Page 30
EL280DF BURNER, COMBUSTION AIR INDUCER ASSEMBLY & HEAT EXCHANGER REMOVAL
FIGURE 24
burners
burner box assembly
manifold and gas valve retention rings
cross over
Repair Parts List
The following repair parts are available through indepen-
dent Lennox dealers. When ordering parts, include the
complete furnace model number listed on the CSA Interna-
tional nameplate Example: EL280DF110P60C.
All service must be performed by a licensed profes-
sional installer (or equivalent), service agency, or gas
supplier.
Cabinet Parts
Main access panel
Blower access panel
Top cap
Control Panel Parts
Transformer
Integrated control
Door interlock switch
Circuit breaker
Blower Parts
Blower wheel
Blower housing
Motor
Motor mounting frame
Blower housing cutoff plate
Heating Parts
Flame Sensor
Heat exchanger assembly
Gas manifold
Combustion air inducer
Gas valve
Main burner cluster
Main burner orifices
Pressure switches
Ignitor
Primary limit control
Flame rollout switch
Secondary limit
Page 31
StartUp & Performance Check List
Unit Model Number_______________
Serial Number___________________
UNIT SET UP (typical)
Gas Supply Pressure
1
2
2
1
SUPPLY AIR
Line Voltage
3
4
5
Filter
RETURN AIR
GAS SUPPLY
Natural Gas LP/Propane Gas
Piping Connections Tight
Leak Tested
Supply Line Pressure W.C.________
1
VENT / EXHAUST PIPE
Secure to Unit
Elbows Secured to Pipe
Vent Pipe Supported
2
Roof Flashing (water tight)
3 DUCT SYSTEM
SUPPLY AIR DUCT
Sealed
Insulated (if necessary)
Registers Open and Unobstructed
RETURN DUCT
Sealed
Filter Installed and Clean
Grilles Unobstructed
4
5
INTEGRATED CONTROL
DIP Switches Set (if applicable)
Appropriate Links in Place (if applicable)
VOLTAGE CHECK
Supply Voltage _____
Electrical Connections Tight
upflow furnace shown
Page 32
Contractors: Name_________________________Telephone_____________Checklist Completed____________________
Job Address_____________________________________Technicians Name___________________________________
UNIT OPERATION (typical)
1
HEATING MODE
GAS MANIFOLD PRESSURE W.C._____
COMBUSTION SAMPLE CO2%______CO PPM_______2
INDOOR BLOWER AMPS______3
TEMPERATURE RISE4
Supply Duct Temperature ________
Return Duct Temperature _ _____
Temperature Rise = ________
5
COOLING MODE
INDOOR BLOWER AMPS______3
TEMPERATURE DROP
Return Duct Temperature _________
Supply Duct Temperature _ _______
4
5
6
7
DRAIN LINE
Leak Free
THERMOSTAT
Adjusted and Programmed
Operation Explained to Owner
RETURN AIR
SUPPLY AIR
6
7
Blower Motor Amps
3
Thermostat
2
Combustion CO2
Duct Static
Gas Manifold Pressure
1 4
5
Temperatures
Filter
Temperature Drop = _________
TOTAL EXTERNAL STATIC (dry coil)
Supply External Static _______
Return Ex
Related manuals for Lennox EL280DF Installation Instructions
Manualsnet FAQs
If you want to find out how the EL280DF Lennox works, you can view and download the Lennox EL280DF Installation Instructions on the Manualsnet website.
Yes, we have the Installation Instructions for Lennox EL280DF as well as other Lennox manuals. All you need to do is to use our search bar and find the user manual that you are looking for.
The Installation Instructions should include all the details that are needed to use a Lennox EL280DF. Full manuals and user guide PDFs can be downloaded from Manualsnet.com.
The best way to navigate the Lennox EL280DF Installation Instructions is by checking the Table of Contents at the top of the page where available. This allows you to navigate a manual by jumping to the section you are looking for.
This Lennox EL280DF Installation Instructions consists of sections like Table of Contents, to name a few. For easier navigation, use the Table of Contents in the upper left corner.
You can download Lennox EL280DF Installation Instructions free of charge simply by clicking the “download” button in the upper right corner of any manuals page. This feature allows you to download any manual in a couple of seconds and is generally in PDF format. You can also save a manual for later by adding it to your saved documents in the user profile.
To be able to print Lennox EL280DF Installation Instructions, simply download the document to your computer. Once downloaded, open the PDF file and print the Lennox EL280DF Installation Instructions as you would any other document. This can usually be achieved by clicking on “File” and then “Print” from the menu bar.