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• To achieve the best performance and minimize
equipment failure it is recommended that a yearly
maintenance checkup be performed. At a minimum,
this check should include the following items:
Air Filter(s)
WARNING:
Never operate the furnace without a fi lter in
place. Dust and lint in the return air can build
up on internal components, resulting in loss of
effi ciency, equipment damage, and possible fi re.
Note:
Air fi lter(s) are not supplied with the furnace as
shipped from the factory. The installer must provide a
high velocity fi lter and rack for a fi lter in the return air
duct adjacent to the furnace, or in a return air grill to the
furnace. It is recommended that fi lters be 1” or 2” thick and
be cleaned or replaced monthly. New or newly renovated
homes may require more frequent changing until the
construction dust has minimized.
Filters designed to remove smaller particles such as
pollen, may require additional maintenance. Filters for
side return and bottom return applications are available
from most local distributors.
Blower Compartment
Dirt and lint can create excessive loads on the motor
resulting in higher than normal operating temperatures
and shortened service life. It is recommended that the
blower compartment be cleaned of dirt or lint that may
have accumulated in the compartment or on the blower
and motor as part of the annual inspection.
Cleaning of Burners
If the burners must be cleaned, follow the steps below and
see Figure 28 (page 41) for component location.
1. Shut off gas supply to the furnace either at the meter
or at a manual valve in the supply piping.
2. Turn off all power to the furnace and set the thermostat
to its lowest setting.
3. Remove the burner door from the furnace.
4. Turn the gas control knob to the OFF position.
5. Disconnect the wires from the gas valve, igniter, fl ame
sensor, and fl ame rollout switch.
CAUTION:
To prevent damage to the unit or internal
components, it is recommended that two
wrenches be used when loosening or tightening
nuts. Do not over tighten!
6. Using two wrenches, separate the ground-joint union
in the gas supply piping at the furnace.
7. Remove the piping between the gas valve and the
ground-joint union. (If applicable).
8. Remove all screws securing the burner assembly to
the furnace.
9. Carefully remove the burner assembly from the furnace.
DO NOT DAMAGE THE IGNITER WHILE REMOVING
THE BURNER ASSEMBLY.
10. Inspect the burners for accumulated dust or debris.
If necessary carefully clean them with a soft wire
brush and a vacuum cleaner.
DO NOT DAMAGE THE
IGNITER WHILE CLEANING THE BURNER.
11. Replace all the parts in reverse order that they were
removed.
12. Follow the lighting instructions found on the furnace
door to return the furnace to operation. Verify proper
operation after servicing.
Cleaning Of Flue Passages
If the fl ue passages must be cleaned, follow the steps
below. See Figure 28 for component location.
1. Shut off the gas supply to the furnace at the meter or
at the manual valve in the gas supply piping.
2. Turn off all power to the furnace and set the thermostat
to the lowest temperature setting.
3. Remove the blower door from the furnace.
4. Turn the gas control switch to the OFF position.
5. Disconnect the wires from the gas valve, fl ame sensor,
inducer, fl ame roll-out switch, limit switch, pressure
switch and igniter.
6. Remove the silicone rubber tube from the inducer.
7. Using two wrenches, separate the ground-joint union
in the gas supply piping at the furnace.
8. Remove the piping between the gas valve and the
ground-joint union. (If applicable).
9. Remove all screws securing the burner assembly to
the furnace.
10. Carefully remove the burner assembly from the
furnace.
DO NOT DAMAGE THE IGNITER WHILE
REMOVING THE BURNER ASSEMBLY.
11. *TA models - Remove all screws securing the inducer
assembly to the vent pipe running out of the furnace
*TK models - Remove all screws securing the
combustion air tube assembly to the vent pipe running
out of the furnace.
12. Remove all screws securing the inducer assembly to
the collector pan.
13. *TA models - Carefully remove the inducer assembly
from the furnace.
*TK models - Carefully remove the inducer assembly
and combustion tube assembly from the furnace.
DO
NOT BREAK THE SEALS AT EACH END OF THE
COMBUSTION AIR TUBE.
14. Remove all screws securing the collector pan to the
furnace.
15. Remove the collector pan and gasket from the furnace.