Haier HSM18HEKC03/R2 Service Manual page 62

Indoor display:
outdoor display:
Exhaust temperature sensor failure
Indoor display:
outdoor display:
Ambient temperature sensor failure
Indoor display:
outdoor display:
Method of This type of error is detected by checking the thermistor input voltage to the microcomputer.
Malfunction (A thermistor error is detected by checking the temperature)
Detection
Malfunction The thermistor input is above 4.9V or below 0.1V with the power on.
Decision
Conditions * Note: The values may vary slightly in some models
Supposed
Causes
Troubleshooting * Caution Be sure to turn off power switch before connect or disconnect connector, or
Check the connector connection.
Is it normal?
Thermistor resistance check
Is it normal?
Replace the outdoor unit PCB
7.3.6 Overheat Protection For Exhaust Temperature
Indoor display
HSM18HEKC/HRAC03/R2(DB)HUM18HC03/R2(DB)-SM
F21
LED1 flash 10 times:
F25
LED1 flash 13 times:
F6
LED1 flash 12 times:
Faulty connector connection
Faulty thermistor
Faulty PCB
else parts damage may be occurred.
NO
YES
YES
F4
Correct the connection
NO
Replace the thermistor
60
Service Diagnosis
Domestic Air Conditioner