Table 3-2. TROUBLESHOOTING

TM 5-4120-359-14

Table 3-2. TROUBLESHOOTING (cont.)

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

Step 4.

Check that condenser air is not blocked.

Remove any obstruction from condenser inlet or discharge.

Step 5.

Check that high pressure cutout reset is not tripped.

Press in to reset.

Step 6.

After 15 minutes of operation in COOL MODE with TEMPERATURE CONTROL set to COOLER

position, check sight glass. Refrigerant should be clear and center indicator should be green.

If refrigerant is milky/bubbly or center indicator is yellow, report condition to direct support

maintenance.

INSUFFICIENT HEATING.

Step 1.

Check to see that MODE SELECTOR SWITCH is properly positioned.

Set switch to LOW HEAT or HIGH HEAT.

NOTE

During LOW HEAT operation only, one bank of the heaters (nine) is operational.

These heaters are thermostatically controlled by the TEMPERATURE CONTROL.

During HIGH HEAT operation, the second bank of the heaters (six) operate

continuously.

Step 2.

Check that TEMPERATURE CONTROL is set to WARMER position.

Set TEMPERATURE CONTROL to WARMER position.

Step 3.

Inspect fresh and return air filters for dirt or blockage.

Clean filter(s)/remove blockage

RUN INDICATOR LIGHT DOES NOT ILLUMINATE WITH AIR CONDITIONER OPERATING

Step 1.

Press light in. Light should illuminate.

Replace bulb.

Change 6 3-21