6
is found on this and the following pages. However, before begin-
ning maintenance, follow these safety precautions:
FILTERING OUT TROUBLE
A dirty filter will cause excessive stress on the furnace, heat
exchanger, and blower motor and can cause it to overheat
and automatically shut down. The furnace filter should be
checked every 4 weeks or so and cleaned or replaced if
necessary.
If installed with factory specified disposable media filter,
check or replace filter before each heating and cooling
season. Replace disposable media filter at least twice
a year.
If your furnace filter needs replacing, be sure to use the
same size and type of filter that was originally specified.
The air filter for the furnace may be located in a filter cabinet
attached to the side or bottom of the furnace. If air filter has
been installed in another location, contact your dealer for
instructions. To inspect, clean and/or replace the air filter(s),
follow these steps:
1. Turn off the electrical supply to the furnace. (See
Fig. 7.)
2. Remove filter cabinet door (See Fig. 18 and 19.)
NOTE:
It may be necessary to remove 1 thumbscrew.
3. Slide air filter out of filter cabinet. Keep dirty side up (if
dirty) to avoid spilling dirt. (See Fig. 20 and 21.)
4. Inspect the filter. If torn, replace it.
NOTE:
If a washable filter has been replaced with:
a) Factory specified disposable media filter – Do not clean.
If dirty, replace only with media filter having the same
part number and size. Install with airflow direction arrow
pointing towards blower.
b) Electronic air cleaner (EAC) – Refer to EAC Owner’s
Manual for maintenance information.
5. Wash filter (if dirty) in sink, bathtub, or outside with a gar-
den hose. Always use cold tap water. A mild liquid deter-
gent may be used if necessary. Spray water through filter
in the opposite direction of airflow. Allow filter to dry.
6. Reinstall clean air filter
7. Replace filter cabinet door. (See Fig. 22 and 23.)
8. Turn on electrical supply to furnace (See Fig 12).
NOTE:
If side return ducts are used, 2 filters may be required
in some models.The procedure listed above may be used to
remove side filters.
* Recommended ** Some furnaces may have 2 filters
Filters may be field modified by cutting filter material and support rods (3)
in filters. Alternate sizes and additional filters may be ordered from your
dealer.
COMBUSTION AREA AND
VENT SYSTEM
Inspect the combustion area and vent system before each
heating season. An accumulation of dirt, soot, or rust can
mean a loss of efficiency and improper performance. Build-
ups on the main burners can cause faulty firing. This “delayed
ignition’’ is characterized by an alarmingly loud sound. If
your furnace makes a loud noise when the main burners are
ignited, shut down the furnace and call your servicing dealer.
Use your flashlight and follow these steps for inspecting the
combustion area and vent system of your furnace:
1. Turn off electrical supply to the furnace and remove
the access door. (See Fig. 7 and 8.)
2. Carefully inspect the gas burner for dirt, rust, or scale
(See Fig. 17.) Inspect the elbow, flue connection
area, and the vent pipe for rust.
17
NOTE:
If dirt, rust, soot, or scale accumulations are found, call
your servicing dealer. DO NOT OPERATE THE FURNACE.
WARNING
Turn off electrical power supply to your furnace
before removing the access doors to service or
perform maintenance. A failure to follow this
warning could result in personal injury or death.
CAUTION
Although special care has been taken to minimize
sharp edges, be extremely careful when handling
parts or reaching into the furnace.
CAUTION
Never operate your furnace without a filter in place.
Doing so may damage the furnace blower motor.
An accumulation of dust and lint on internal parts
of your furnace can cause a loss of efficiency.
!
!
!
FURNACE CAS-
ING WIDTH
FILTER QUANTITY
AND SIZE
**
FILTER TYPE
*
SIDE
RETURN
BOTTOM RETURN
14-1/2
(1) 16 x 25
(1) 14 x 25
1” thick cleanable
or 4-5/16” thick
media-type
17-1/2
(1) 16 x 25
(1) 16 x 25
1” thick cleanable
or 4-5/16” thick
media-type
21
(1) 16 x 25
(1) 20 x 25
1” thick cleanable
or 4-5/16” thick
media-type
24
(1) 16 x 25
(1) 24 x 25
1” thick cleanable
or 4-5/16” thick
media-type
CAUTION
Use care when cutting support rods in filters to
protect against flying pieces and sharp rod ends.
Wear safety glasses, gloves, and appropriate pro-
tective clothing. Failure to follow this caution
could result in personal injury.
!
