Mitsubishi Electric PUHY-P72 Service Manual page 255

[ IX Troubleshooting ]
[THMU-A]
(2) Inverter output related troubles
Items to be checked
[1] <P72 and P96 models>
Check the INV
board error
detection cir-
cuit.
(1) Disconnect the invert-
er output wire from
the terminals of the
INV board (SC-U,
SC-V, SC-W).
(2) Put the outdoor unit
into operation.
<P120 model>
(1) Disconnect the invert-
er output wire from
the output terminals
(U, V, W) of the IPM.
(2) Put the outdoor unit
into operation.
[2] Disconnect the compres-
Check for sor wiring, and check the
compressor compressor Meg, and coil
ground fault or resistance.
coil error.
HWE0804A
Phenomena
1) IPM/overcurrent breaker trip
Error code: 4250
Detail code: No. 101, 104, 105, 106,
and 107
2) Logic error
Error code: 4220
Detail code: No. 111
3) ACCT sensor circuit failure
Error code: 5301
Detail code: No.117
4) IPM open
Error code: 5301
Detail code: No.119
1) IPM/overcurrent breaker trip
Error code: 4250
Detail code: No. 101, 102, 103, 104,
105, 106, and 107
2) Logic error
Error code: 4220
Detail code: No. 111
3) ACCT sensor circuit failure
Error code: 5301
Detail code: No.117
4) DCCT sensor circuit failure
Error code: 5301
Detail code: No.118
5) IPM open
Error code: 5301
Detail code: No.119
1) Compressor Meg failure
Error if less than 1 Mohm.
When no liquid refrigerant in the
compressor
2) Compressor coil resistance failure
Coil resistance value of 0.3 ohm
(20°C [68°F]) : -P96 models
Coil resistance value of 0.3 ohm
(20°C [68°F]) : P120 model
- 246 -
Remedy
Replace the INV board.
Replace the INV board.
Replace the INV board.
Normal
See the section "Troubleshooting
the IPM" ( Refer to - 6 - [5] ).
Replace the IPM, and put the out-
door unit back into operation.
If the problem persists, replace the
INV board.
See the section "Troubleshooting
the IPM" ( Refer to - 6 - [5] ).
Replace the IPM, and put the out-
door unit back into operation.
If the problem persists, replace the
INV board.
Replace the INV board, and put
the outdoor unit back into opera-
tion.
If the problem persists, replace the
DCCT.
Replace the INV board.
Replace the DCCT board.
Replace the DCCT, and put the
outdoor unit back into operation.
If the problem persists, replace the
INV board.
Normal
Replace the compressor
Check that no liquid refrigerant in
the compressor.
GB