Haier 2U40S2SM1FA, Service Manual, Page: 46 / 73

10.4.9 Overheat Protection For Discharge Temperature
Outdoor display: LED1 flash 8 times
Method of The Discharge temperature control is checked with the temperature being detected
Malfunction by the Discharge pipe thermistor
Detection
Malfunction when the compressor discharge temperature is above 116
Decision
Conditions
Supposed Electronic expansion valve defective
Causes Faulty thermistor
Faulty PCB
Troubleshooting * Caution Be sure to turn off power switch before connect or disconnect connector, or
else parts damage may be occurred.
Electrify the machine again and turn it on with the remote controller,
then measure the temperature at the exhaust temperature sensor of
the compressor on the outdoor unit
The temperature exceeds
116
shortly after the
machine starts up?
1) The cryogen may have been leaked during
installation, or there may be leakage in the piping
system.
2) There may be other causes to make the exhaust
temperature too high.
Malfunctions occur after running for some time even
though the measured temperature is below 116 . Pull
out the exhaust sensor and measure its resistance at
standard
temperatures according to the
resistance-temperature table
The results deviate
much?
The sensor is damaged. Replace the sensor
with a new one.
The outdoor mainboard is damaged and needs be
replaced
YES
NO
NO
YES
Service diagnosis
Domestic air conditioner
44