Carrier 48SS018-060, 48SX024-060 user manual Burner Access Panel

Combustion-Air Blower Ð Clean periodically to as- sure proper air¯ow and heating efficiency. Inspect blower wheel every fall and periodically during heating season. For the ®rst heating season, inspect blower wheel bimonthly to determine proper cleaning frequency.

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 induced-draft motor mount- ing plate to blower housing. (See Fig. 34.)

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 self-diagnostic LED. During servicing, refer to label diagram for LED interpretation.

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

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