TM 9-4120-399-14
Table 4-3. Unit Troubleshooting. (Continued).
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
4.
REDUCED COOLING CAPACITY. (Continued).
Check to be sure that excessive hot, outside air is not being
Step 3.
introduced through the fresh air dampers.
Fully close damper; then, if condition improves, adjust properly.
Check to be sure that condenser air inlet and outlet are not
Step 4.
obstructed.
Remove obstructions.
If air volume is low:
Step 5.
Clean or replace air conditioner filter.
Clean evaporator coil.
Check to be sure that condenser damper is operating properly.
Step 6.
If damper is not defective, but not operating, notify your supervisor.
Check operation of temperature selector.
Step 7.
Set control at maximum DECREASE then, if condition improves,
adjust properly.
If conditions do not improve, test mode selector switch per para.
Check operation of temperature control thermostat switch.
Step 8.
Inspect sensing bulb and capillary for damage or leakage.
Replace switch if damage or leakage is found per para. 4-43.
Test temperature control thermostat switch. Replace defective
4-28