Service diagnosis
38                   Domestic air conditioner 
10.3.9 Overheat Protection For Discharge Temperature 
Outdoor display: ƵƾƵ F4 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 110ć
Decision 
Conditions 
Supposed Ŷ
Electronic expansion valve defective 
Causes Ŷ
 Faulty thermistor 
Ŷ
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 
110 ć  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 110ć. 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