Troubleshooting Sheet

Digital tester
Normal resistance value
Digital tester
Normal resistance value
(+)Red
(-)Black
∞
(Several MΩ)
(+)Red
(-)Black
∞
(Several MΩ)
P
N
U
N
U
V
V
W
W
(+)Red
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 outdoor 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
Check the wiring of L
and N well or correctly
Reconnect it well
Rec
onnect it
well
Check the wiring of
bridge rectifier well or
correctly
Check 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 rectifierNo
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 r
eactor or
inductance
Replace r
eactor 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
M
ake 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 compressorNo
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