Trouble Shooting - Haier H2SM-(9+12)HEK03/R2 Service Manual

7.4. Trouble Shooting

7.4.1 Thermistor or Related Abnormality (indoor unit)
Indoor Display
Method of Malfunction
Detection
Malfunction Decision
Conditions
Supposed Causes
* Caution
Be sure to turn off power switch before connect or disconnect connector, or else parts damage
may be occurred.
Pull the sensor out of the mainboard
1)Measure the value of resistance
Between its two jumpers
2)Measure the temperature at the
room temperature sensing head.
Check the value of the sensor to see
whether the sensor is damaged or not?
The indoor PCB is broken, replace
with new indoor PCB
H2SM-(9+12)HEK03/R2
E1:Room temperature sensor failure
E2:Indoor heat-exchange sensor failure
The temperatures detected by the thermistors are used to determine thermistor errors
When the thermistor input is more than 4.92V or less than 0.08V during compressor
operation. (* Note: The values vary slightly in some models)
Faulty connector connection
Faulty thermistor
Faulty PCB
whether terminal CN8 on
indoor PCB contact wellt?
YES
YES
Pull out the terminals on the indoor
NO
mainboard and reinsert them
Sensor is broken,replace it with new
NO
sensor
49
Service Diagnosis
Domestic Air Conditioner