TM 9-4120-407-14
SECTION V UNIT TROUBLESHOOTING
3-10. USE OF TROUBLESHOOTING TABLE. This table contains troubleshooting information useful to
Unit Maintenance technicians in diagnosing and correcting malfunctions or unsatisfactory operation of the air
conditioner.
a . The Troubleshooting Table lists the common malfunction symptoms and unsatisfactory performance
characteristics technicians are most likely to encounter. Included are test and inspection steps to be followed
to determine the cause and the corrective action(s) that should be performed for each possible cause listed.
b. The technicians should first find the malfunction symptom or unsatisfactory performance
characteristic in the table which most closely describes the immediate situation. Perform the test and
inspections, and corrective action steps in the order in which they are listed.
C. This manual cannot list all possible situations which may be encountered, nor can it list all test and
inspection, and corrective action steps which may be taken. If a condition is encountered which cannot be
resolved within the capabilities and experience of Unit Maintenance personnel, assistance should be
requested from Direct Support Maintenance.
SYMPTOM INDEX
MALFUNCTION NO.
TROUBLE
AIR CONDITIONER DOES NOT START IN ANY MODE ..................
1
2
COMPRESSOR DOES NOT START IN COOL MODE ..........................
CUTOUT SWITCH SOON TRIPS.. ...................................................
3
COOLING CAPACITY REDUCED .......................................................
4
5
HEATING CAPACITY REDUCED .......................................................
6
FRESH AIR DAMPER WILL NOT OPERATE ......................................
7
EVAPORATOR FAN MOTOR SHAFT DOES NOT TURN.. .................
8
CONDENSER FAN MOTOR SHAFT DOES NOT TURN.. ...................
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