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SECTION 3
TROUBLESHOOTING
3-1
INDICATION/
REFERENCE
TROUBLE
POSSIBLE CAUSES
SECTION
3.1 UNIT WILL NOT COOL
Compressor will not run
V-Belt broke or defective
Check
Compressor malfunction
See Note
Clutch malfunction
Check/Replace
Safety device open
1.4
Electrical malfunction
A/C switch defective
Check
A/C relay defective
Check/2.3
Low Ambient Thermostat open
1.5.c
Circuit breaker CB6 open
Check/Reset
Temperature Controller malfunction
3.5
Run Control Switch in OFF position
Check
Liquid Line Solenoid malfunction
4.16
3.2 UNIT RUNS BUT HAS INSUFFICIENT COOLING
Compressor
Compressor valves defective
See Note
V-belt loose
Check
Refrigeration system
Abnormal pressures
3.4
No or restricted evaporator air flow
2.3
Expansion valve malfunction
3.7
Restricted refrigerant flow
3.7
Low refrigerant charge
4.9
Service valves partially closed
Open
Safety device open
1.4
3.3 ABNORMAL PRESSURE
High discharge pressure
Refrigerant overcharge
4.9
Noncondensibles in system
Check Pressure
Condenser fan motor rotation incorrect
Check/Reverse
Motor Electrical
Leads
Condenser coil dirty
Clean
Low discharge pressure
Compressor valves(s) worn or broken
See Note
Low refrigerant charge
4.9
High suction pressure
Compressor valves worn or broken
See Note
NOTE: Refer to 05G Compressor manual, Form T-199.