Willis WST12MC16S Service Manual page 46

(5) Diagnosis of overload and discharge malfunction
Main detection points:
Is electric expansion valve well connected? Is it damaged?
Is refrigerant leaked?
Is overload wire connection normal?
Malfunction diagnosis process:
(6) Process of
62
communication circuit detection
outdoor unit
de-energization of
complete unit
Is electric expansion
valve well connected?
Is overload wire
reliably connected?
Replace electric
expansion valve
Remove malfunction?
Replace parts
of outdoor electric box
Remove malfunction?
Refrigerant leakage,
recharge the refrigerant
E6 communication
error is displayed
Is connecting
N
wire reliably connected?
Y
Replace main
board of indoor unit
Y
Remove malfunction?
N
Replace parts of
outdoor electric box
Finish
20min after
N
Y
N
Y
Y
N
Y
N
Finish
Adjust
connecting wire
Troubleshooting
Adjust
connecting wire