PROBABLE CAUSE
CORRECTIVE ACTION
SYMPTOM
7. Prolonged operation on
Start capacitor open,
Replace capacitor.
start cycle.
shorted, or blown.
Relay mounted incorrectly.
Remount relay in correct
position.
Relay being influenced by
Remount rigidly.
loose or vibrating
mounting.
Prolonged operation on
Correct by using pump
start cycle due to high
down arrangement, if
starting load.
necessary.
8. Space temperature too
Control setting too high.
Reset control.
high.
Environmental control unit
Adjust ECU.
(ECU) temperature too
high.
Inadequate air circulation.
Improve air movement.
9. Suction line frosted or
Expansion valve passing
Replace valve.
sweating.
excess refrigerant.
Expansion valve stuck
Replace valve.
open.
Test fan motor; replace fan
running.
motor, if required.
Overcharge of refrigerant.
Correct charge.
MD0367
A-5