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P
P
Check of outdoor fan motor
Abnormal
Normal
Yes
No
No
Yes
No
Yes
Start
Check the connection of connector (CN851) in the fan motor relay connector and outdoor electronic control P. C. board
at the noise filter P. C. board and connector (CN901) in the noise filter board.
Disconnect the fan motor connector, and measure the resistance of the
fan motor winding to check the winding characteristic.
Is there voltage of 230V AC?
1. Turn off power supply of the indoor and outdoor unit, and disconnect the connector
(CN851).
2. Is the voltage 0V, when the voltage between CN851 pin3 (+), pin7 (-), pin6 (-) are
measured after the power supply is turned on the outdoor unit?
Replace the fan motor
Replace the oudtoor
electronic control P. C.
board
Is there voltage of 12V DC between CN851 pin3 (+) and pin6 (-), when power supply
turns on the indoor unit and EMERGENCY OPERATION starts in three minutes.
1. Disconnect the lead wire leading to the compressor. Turn on power supply to the
indoor and outdoor unit. Three minutes later, start EMERGENCY OPERATION.
2. Check the voltage between pin 3 and pin 4, pin 3 and pin 5 at the fan motor connector.
Replace the noise filter P. C. board
O
O
Check of outdoor unit thermistor
Normal
Yes
No
Abnormal
Reconnect the connector (CN661, CN662 and CN663) and disconnect the lead wire leading to the compressor.
3 minutes after turning on the power supply, start EMERGENCY OPERATION.
Start
Disconnect the connector in the outdoor electronic control P. C. board (see below table),
and measure the resistance of thermistor to check whether the thermistor is normal or not.
Thermistor
Discharge temperature thermistor
Defrost thermistor
Evaporation temperature thermistor
High-pressure protect thermistor
Gas pipe temperature A thermistor
Gas pipe temperature B thermistor
Fin temperature thermistor
Symbol
RT61
RT62
RT63
RT68
RT6A
RT6B
RT65
Connector, Pin No.
Between CN662 pin3 and pin4
Between CN662 pin1 and pin2
Between CN662 pin5 and pin6
Between CN662 pin7 and pin8
Between CN661 pin1 and pin2
Between CN661 pin3 and pin4
Between CN663 pin1 and pin2
Does thermistor operate 10 minutes or more though the
thermistor abnormality is not displayed?
Replace the thermistor
Normal
Replace the outdoor electronic
control P. C. board.
• When thermistor is abnormal. (When the LED display is a table below.)
• Fan motor does not operate or stops operating shortly after starting the operation.
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