Midea MHC-96HWD1N1(A) Service Manual page 53

MCAC-UTSM-201503
Step 2: Disconncet the power wiring from the compressor(named compressor A) of the faulted
system(named system A).
If there is a system running normally nearby(named system B):
Extend the power line of the inverter compressor of system B, connect compressor A to the control box of
system B, make sure that the U, V, W terminals are connected in right order, then start system B.
If compressor A can start normally, that means compressor is OK, the control box of system A is
malfunction, then raplace the main PCB of system A with correct wire connection.
If compressor A can not start normally, that means compressor A is demaged, needs to be replaced.
If there is no normal system nearby:
Replace the main PCB of system A with correct connection, if compressor A can start normally, it means
the main PCB which is replaced is damaged. If compressor A still can't start normally, replace the
compressor.

P9: DC Fan module protection
P9/H9: Fan module protection
The fan module is too hot for bad
heat dissipation or high ambient
temperature
No
Some power wires or signal
wires of fan module are loose
No
The fan motor is blocked or disabled
No
Output voltage between P and
N on fan module is abnormal*
No
Fan module is disabled
Notes: There are three times in 60 minutes, 'H9' will be displayed. Repower-on, the protection will be
canceled. At the same time, the reason of protection should be settled.
R410A Full DC Inverter Split Duct Type Technical Manual
Yes
Make sure the fan module working
in the normal temperature range
Yes Well connect the power wires
and signal wires
Yes
Clear away the block or replace
the fan motor
Yes
Replace the power supply module
Yes
Replace the fan module
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