NO
YES
YES
YES
•
Measure coil resistance of
starting relay. (SR)
•
Measure resistance of
compressor motor winding.
•
Check capacitors.
(Either C or BC)
•
Either internal protector or
overload relay is working.
(49C or OLR)
YES
•
Temperature of compressor
is abnormally high.
Refrigerant gas shortage. Charge refrigerant gas (R22).
Rotor may be locked up.
•
Measure coil resistance of
power relay. (PR)
Fan cannot
be turned.
OK
•
Check fan rotation.
Turn fan gently once or twice by
hand.
•
Check fan casing
foreign matter on
inside.
Fan motor burnout
or foreign matter in
bearings.
Remove foreign
matter or repair.
Repair or replace.
•
Measure resistance of outdoor fan
motor winding.
•
Check fan motor capacitor.