Mitsubishi Electric MUZ-GB50VA, Service Manual

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30
MUZ-GB50VA-
E1
/
E2
Thermistor Symbol Connector, Pin No. Board
Defrost RT61 Between CN661 pin 1 and pin 2
Outdoor electronic control P.C. board
Discharge temperature RT62 Between CN661 pin 3 and pin 4
Outdoor heat exchanger temperature RT68 Between CN661 pin 7 and pin 8
Ambient temperature
RT65 Between CN663 pin 1 and pin 2
Fin temperature RT64 Between CN3 pin 1 and pin 2 Outdoor power board
MUZ-GB50VA-
E3
Thermistor Symbol Connector, Pin No. Board
Defrost RT61 Between CN641 pin1 and pin2
Inverter P.C. board
Discharge temperature RT62 Between CN641 pin3 and pin4
Fin temperature RT64 Between CN642 pin1 and pin2
Ambient temperature RT65 Between CN643 pin1 and pin2
Outdoor heat exchanger temperature RT68 Between CN644 pin1 and pin3
Replace the thermistor except RT64.
When RT64 is abnormal, replace the inverter P.C.
board or the outdoor power board.
Replace the inverter P.C. board
or the outdoor power board.
No
No
Is the thermistor normal? (Refer to 11-6.1.
or 4.)
Reconnect the connector of thermistor.
Turn ON the power supply and press EMERGENCY OPERATION switch.
Does the unit operate for 10 minutes or more
without showing thermistor abnormality?
OK.
(Cause is poor contact.)
Yes
Yes
G Check of outdoor thermistors
Disconnect the connector of thermistor in the outdoor P.C. board (see
below table), and measure the resistance of thermistor.