Troubleshooting Sheet
For 30K~36K: 
At first test the resistance between every two ports of U, V, W of IPM and P, N. If any result of them is 0 or 
close to 0, the IPM is defective. Otherwise, please follow the procedure below: 
Yes
Check whether the power voltage 
is normal
.
Check whether the power voltage 
is normal.
Measure whether outdoor terminal 
voltage is normal?
Measure whether o
utdoor terminal 
voltage is normal?
Restart the unit when the power supply 
gets normal
Restart the unit when the power supply 
gets normal
No
Yes
No
Reconnect 
it
 well
Rec
onnect 
it 
well
Yes
Measure whether 
the voltage 
between L and N is
 normal
?
Measure whether the voltage 
between
 L
and N 
is 
normal
?
Yes
Measure whether input voltage of 
bridge rectifier 
is normal
?
Measure whether input voltage of 
bridge rectifier is normal?
No
No
 Check the wiring of 
power wires well or 
correctly
 Check the wiring of 
power wires well or 
correctly
Reconnect it well
Reconnect it well
Check the wiring of L 
and N well or correctly
C
heck the wiring of L 
and N well or correctly
Rec
onnect 
it
 well
Reconnect
it 
well
 Check the wiring of 
bridge rectifier well or 
correctly
 C
heck the wiring of 
bridge rectifier well or 
correctly
No
Yes
Replace the PFC module(If has)
Replace the PFC module(If has)
No
Measure whether 
the voltage 
between 
P 
and N
 is
 normal 
refer to the 
Appendix 4?
Measure whether 
the voltage 
between P and N is normal 
refer to the Appendix 
4
?
Replace the bridge rectifier
Replace the 
bridge rectifier
No
Check whether 
bridge 
rectifier is normal
Check whether 
bridge 
rectifier is normal
Check the wiring of reactor 
or 
inductance
Check the wiring of reactor 
or inductance
Reconnect the wiring 
Reconnect the wiring No
Check whether reactor or 
inductance is normal
Check whether reactor or 
inductance is normal
Yes
Replace reactor 
or 
inductance
Replace reactor or 
inductance
No
Check whether the connecting 
wire 
between main board and the 
IPM board is connected tightly
Check whether the connecting 
wire
 between main board and the 
IPM board is connected tightly
Reconnect it well
Reconnect it well
No
Check if the outdoor unit 
ventilation is good
Check if the outdoor unit 
ventilation is good
Yes
Make the outdoor unit ventilate well
Make the outdoor unit ventilate well
Check whether the refrigerant system is ok
Check whether the refrigerant system is ok
No
Check if the outdoor fan runs 
properly
Check if the outdoor fan runs 
properly
please refer to the solution of [fan speed 
has been out of control malfunction] . 
Find out the cause and have it solved.
please refer to the solution of [fan speed 
has been out of control malfunction]
 . 
Find out the cause and have it solved.
No
Yes
No
Yes
Yes
Check the compress is 
normal
Check the compress is 
normal
Yes
Replace the compressor
Replace the compressor
No
 Replace 
IPM board
 Replace 
IPM 
board
 Replace the outdoor main PCB
 Replace the outdoor main PCB
No
Check whether the connecting 
wire of the compressor is 
connected correctly or tightly
Check whether the connecting 
wire 
of the compressor is 
connected correctly or tightly
Reconnect
 it well
Reconnect
 it well
No
Yes
Yes










