ENGINEMAN 1 & C
Trouble
Compressor will not run.
(Contd)
Sudden loss of oil from
crankcase.
Possible Cause
4. Fuses blown.
5. Over-load relays tripped.
6. Low voltage.
7. Electrical motor in trouble.
8. Trouble in starting switch
or control circuit.
9. Compressor motor stopped
by oil pressure differ-
ential switch.
Liquid refrigerant slugging
back to compressor crank
case.
Capacity reduction system
fails to unload cylinders.
Hand operating stem of
capacity control valve not
turned to automatic position.
Compressor continues to
operate at full or partial load.
Pressure regulating valve
not opening.
Capacity reduction system
fails to load cylinders.
Broken or leaking oil tube
between pump and power
element.
Compressor continues to
operate unloaded.
Pressure regulating valve
not closing.
Corrective Measure
4. Test fuses and renew
if necessary.
5. Re-set relays and find
cause of overload.
6. Check voltage (should
be within 10 percent of
nameplate rating).
7. Repair or replace motor.
8. Close switch manually to
test power supply. If
OK check control circuit
including temperature and
pressure controls.
9. Check oil level in crank-
case. Check oil pump
pressure.
Adjust or replace expansion
valve.
Set hand operating stem to
automatic position.
Adjust or repair pressure
regulating valve.
Repair leak.
Adjust or repair pressure
regulating valve.
54.299.3
Figure 6-12.Trouble diagnosis chart-Continued.
6-20