Haier HSU12VHJ(DB), Service Manual

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Domestic Air Conditioner
7.3.1Thermistor or Related Abnormality (indoor unit)
Indoor Display
E1 : Room temperature sensor failure
E2 : Heat-exchange sensor failure
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 Ƶ Faulty connector connection
Causes Ƶ Faulty thermistor
Ƶ
Faulty PCB
Troubleshooting * Caution Be sure to turn off power switch before connect or disconnect connector, or
else parts damage may be occurred.
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.
Thermistor resistance check
Is it normal?
Yes
NO
Yes
Is it normal?
NO
Check the connector
i
Correct the connection
Replace the thermistor
Replace the indoor unit PCB
HSU12/18VHJ(DB) Functions and control
56