TM 9-4120-385-14
Table 4-2. TROUBLESHOOTING FOR UNIT MAINTENANCE
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
Step 3. Inspect shelter or van for openings that allow cold air to move inside.
Seal all openings.
Step 4. Check for air movement out of discharge air outlet louver and into return
air inlet.
Remove
obstructions
from
air
inlet/outlets.
Clean return air filer. Refer to Paragraph 4-14.
Clean mist eliminator.Refer to Paragraph 4-15.
NOTE
This unit can operate in temperatures as low as -50 F (10 C).
However, depending on shelter or van size, heat loss, and amount of
heat generated by equipment, heat output in the LO HEAT mode
may or may not heat shelter or van to a comfortable level.
Step 5. Check thermostatic switch S3.
Replace if defective. Refer to Paragraph 4-25
Step 6. Check mode selector switch S.
Replace if defective. Refer to Paragraph 4-18.
Step 7. Check relay K2.
Replace if defective. Refer to Paragraph 4-20.
WARNING
Allow heater elements to cool before handling. Severe burns can
result from touching heater elements.
4-20
