To inspect blower wheel, remove draft hood assembly. Shine a ¯ashlight into opening to inspect wheel. If cleaning is re- quired, remove motor and wheel as follows:
1.Remove burner access panel. (See Fig. 35.)
2.Remove the 7 screws that attach
3.Slide the motor and blower wheel assembly out of the blower housing. (See Fig. 36.) Clean the blower wheel. If additional cleaning is required, continue with Steps 4 and 5.
4.To remove blower, remove 2 setscrews. (See Fig. 36.)
BURNER
ACCESS
PANEL
Fig. 35 Ð Burner Access Panel
BLOWER
HOUSING
2 SETSCREWS (HIDDEN)
5.To remove motor, remove 4 screws that hold blower hous- ing to mounting plate. Remove the motor cooling fan by removing one setscrew. Remove nuts that hold motor to mounting plate.
6.To reinstall, reverse the procedure outlined above.
Limit Switch Ð Remove blower panel. Limit switch is located on the gas partition.
Burner Ignition Ð Unit is equipped with a direct spark ignition 100% lockout system. Ignition module is lo- cated in the control box. Module contains a
If lockout occurs, unit may be reset by either momentarily interrupting power supply to unit, or turning selector switch to OFF position at the thermostat.
Main Burners Ð At the beginning of each heating sea- son, inspect for deterioration or blockage due to corrosion or other causes. Observe the main burner ¯ames and adjust if necessary.
When servicing gas train, do not hit or plug ori®ce spuds.
REMOVAL OF GAS TRAIN
1.Shut off manual gas valve.
2.Shut off power to unit.
3.Remove burner access panel. (See Fig. 35.)
4.Disconnect gas piping at unit gas valve.
5.Remove wires connected to gas valve. Mark each wire.
6.Remove ignitor and sensor wires at the ignitor module.
7.Remove the mounting screw that attaches the burner rack to the basepan. (See Fig. 34.)
8.Slide the burner rack out of the unit. (See Fig. 34 and 37.)
9.To reinstall, reverse the procedure outlined above.
Fig. 36 Ð Removal of Motor and Blower Wheel
Fig. 37 Ð Burner Rack Removed
46
