Haier 1U50JECFRA-3 Service Manual page 35

10.3.1 Thermistor or Related Abnormality
Indoor Display
Outdoor display
Method of The temperatures detected by the thermistors are used to determine thermistor errors
Malfunction
Detection
Malfunction When the thermistor input is more than 4.92V or less than 0.08V during compressor
Decision operation.
Conditions
Note: The values vary slightly in some models
Supposed
Causes
Troubleshooting * Caution Be sure to turn off power switch before connect or disconnect connector,
Check the connector connection.
Thermistor resistance check
Thermistor resistance check method:
Remove the connector of the thermistor on the PCB, and measure the resistance of thermistor using tester.The
relationship between normal temperature and resistance is shown in the value of indoor thermistor.
E1: Room temperature sensor failure
E2: Heat-exchange sensor failure
LED1 flash 10 times Defrost temperature sensor failure
LED1 flash 11 times Suction temperature sensor failure
LED1 flash 12 times Ambient temperature sensor failure
LED1 flash 13 times Discharge temperature sensor failure
Faulty connector connection
Faulty thermistor
Faulty PCB
else parts damage may be occurred.
Is it normal?
Yes
Is it normal?
NO
Correct the connection
NO
Replace the thermistor
Yes
Replace the indoor unit PCB
33
Service diagnosis
Domestic air conditioner
or