Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 172

SCM-HG (4 room)
Outdoor unit e rror
Over current
Power transistor overheat
Compressor overheat
170
Is output voltage applied to all 3
phases of power transistor?
YES
Is compressor wiring connected
securely?
YES
Inspect compressor. (Broken coil
wire)
Is refrigerant charge quantity adequate?
YES
Is outdoor ventilation condition good?
YES
Inspect compressor.
YES
Defective inverter
Is outdoor fan motor operating
properly?
YES
Is there any shortcircuit?
YES
Defective inverter
Is discharge pipe sensor resistance
value good?
YES
Is sufficient quantity of refrigerant
circulated?
YES
Defective inverter
NO
Defective inverter
NO
Connect securely.
[Overload operation, compressor
lock, overcharge]
NO
Discharge refrigerant.
NO
Secure space for inlet and outlet.
NO
Inspect outdoor fan motor.
NO
Secure space for inlet and outlet.
NO
Connector connection check, resistancevalue
check, replacement of discharge pipe sensor
NO
Does trouble persist after
charging gas?
YES
Clogged capillary tube,
etc.
[Broken power transistor,
broken compressor wire]
[Poor cooling]
[Gas shortage, defective
discharge pipe sensor]
NO
Gas shortage