61
Service Manual
Installation and Maintenance
7. Diagnosis for overload and discharge malfunction (AP1 below is control board of outdoor unit)
Main detection point:
● If the electron expansion valve is connected well? Is the expansion valve damaged?
● If the refrigerant is leakage?
● If the overload protector is damaged?
Malfunction diagnosis process:
Connect wire 
well with wiring 
diagram
Replace EKV 
coil of electron 
expansion valve
If the wiring terminal FA of electron 
expansion is well connected?
Remove 
malfunction?
The resistance value of 
firs t 4 lead fo ot  an d th e 
fifth lead  foot is similar,  
less than 100
de-energized 
for 20min
Remove 
malfunction?
Y
N
N
N
If the overload protector SAT 
is well connected?
N
Under ambient temperature, test the 
resistance of  overload protector  with ohmic 
Y
Y
Replace 
overload 
protector SAT
N
Y
Check refrigerant, if there is 
leakage, please refer to 
specification
Replace 
control board 
AP1
End