Operating instructions

TM 11574A-OI
3-55
(3) Component(s) not operating.
Step Probable Cause Remedy
1 Evaporator fan motor internal protector open. Replace evaporator fan IAW 3-10b(12).
If fault is not corrected proceed to step 2.
2 Condenser fan motor internal protector open. Replace condenser fan motor IAW 3-10b(8).
If fault is not corrected proceed to step 3.
3 Compressor internal protector open. Replace Compressor internal protector IAW
3-10b(5).
If fault is not corrected proceed to step 4.
4 High pressure switch open. Check high pressure switch IAW 3-10b(6).
If necessary, replace high pressure switch
IAW 3-10b(6).
If fault is not corrected proceed to step 5.
5 Heat termination thermostat open. Check heat termination thermostat IAW 3-
10b(17)(b).
If necessary, replace heat termination
thermostat IAW 3-10b(18)(o)
If fault is not corrected proceed to a (4).
(4) Compressor hums, but does not start.
Step Probable Cause Remedy
1 Low line voltage. Check low line voltage IAW wiring diagram.
If fault is not corrected proceed to step 2.
2 Single phasing. Check power source for single phasing.
If fault is not corrected proceed to step 3.
3 Shorted or grounded motor windings or
compressor seized.
Replace compressor IAW 3-10b(5).
m. Unit operates long or continuously in cooling.
(1) Container.
Step Probable Cause Remedy
1 Hot load (failure to pre-cool). Normal. Pre-cool hot load.
If fault is not corrected proceed to step 2.
2 Defective box insulation or air leak Repair box insulation or air leak IAW 3-10a.
If fault is not corrected proceed to b (2).