Mitsubishi Electronics MUY-D30NA Air Conditioner User Manual


 
31
Fan motor does not operate or stops operating shortly after starting the operation.
Is the resistance between each ter-
minal of outdoor fan motor normal?
(Refer to 10-4.)
Check the connection between the
connector CN931 and CN932.
Disconnect CN932 from outdoor electronic control P.C. board,
and turn on the power supply.
Rotate the outdoor fan motor manually and measure the voltage
of CN931.
Between 1(+) and 5(-)
Between 2(+) and 5(-)
Between 3(+) and 5(-)
Does the voltage between each terminal become 5 VDC
and 0 VDC repeatedly?
Does the outdoor fan motor rotate smoothly?
Replace the outdoor DC fan motor. Replace the outdoor electronic control P.C. board.
Yes
Yes
No
(Fixed to either 5 or 0 VDC)
No
No
Yes
Outdoor unit does not operate.
Is there voltage of 208 / 230 VAC in the
power supply terminal block?
Check the connecting of parts of main power
supply circuit.
Check the power supply cable.
Turn ON power supply.
Is the output voltage from the noise lter P.C.
board 208 / 230 VAC?
Replace the noise lter P.C. board.
No
Yes
No
Yes
Is the input voltage to the power board 208 /
230 VAC?
Replace the reactor.
No
Yes
Is the input voltage to the outdoor electronic
control P.C. board 294 / 325 VDC?
Replace the power board.
No
Replace the outdoor electronic control P.C. board.
Yes
D Check of outdoor fan motor
E Check of power supply