Midea V4 Plus

R410A DC Inverter VRF V4 Plus W Series 50Hz MCAC-VTSM-2016-04
204 Troubleshooting
3.3 E8: Main unit address error
3.4 E9: Voltage error
Note:
1. How to check whether the compressor is short circuit①:
The normal resistance value of inverter compressor among U V W is 0.7~1.5Ω, and infinity to earth. If the resistance value is out
of the range, the compressor is abnormal.
2. How to check whether the fan motor is short circuit②:
The normal value of DC fan motor coil among U V W is less than 10Ω, and the value of AC fan motor coil is from a few ohm to
hundreds of ohm for different fan motor model. If the measured value is 0Ω, the fan motor is short circuit.
3. How to check whether the inverter module is output error③:
Dial the multimeter to diode file, black pen on P and red pen respectively on U,V,W, if the multimeter displays 0.4~0.7 V, it is
normal; Red pen on N, black pen respectively on U,V,W, if the multimeter displays 0.4~0.7 V, it is normal. Satisfying the above
two conditions at the same time indicates that the inverter module has no problem.
E8: Main unit address error
The ODU's address is more than 3 or
be set repeatedly
The addresses should be set less
than 3 and differently
Outdoor main PCB is
damaged
Replace the outdoor
main PCB
No
Yes
The communication wires H1, H2 and
E are short circuit or disconnected. If
the resistance between H1, H2andE is
zero or very small, the reason is short
circuit; If using the multimeter testing
the communication wires don’t have
belling sound, the reason is
disconnected.
Replace or reconnect the
communication wires
Yes
No
Yes
E5: Voltage error
Voltage of power supply is too high or
too low (the normal voltage between A
and N (B and N, C and N) should be
198V~242V)
Provide normal power supply
Check the high voltage circuit. Whether
the compressor is short circuit①
, fan
motor is short circuit②
, inverter module
is output error③, etc.
Replace the inverter module
or repair related parts
No
No
Yes
Yes
Outdoor main PCB
is damaged
Replace the outdoor
main PCB