COMFORT-AIRE A-DVC09SF-0, Service Manual

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Service Manual - DVC 09/12/18/24 SF Series
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8.2.1 1 Inverter compressor drive error diagnosis and solution (P4)
Error Code
P4
Malfunction conditions An abnormal inverter compressor drive is detected by a special
detection circuit, including communication signal detection,
voltage detection, compressor rotation speed signal detection
and so on.
Possible causes
●
Wiring error
●
IPM malfunction
●
Outdoor fan ass embl y faulty
●
Compressor malfunction
●
Outdoor PCB faulty
Troubleshooting:
Check if the wiring between main
PCB and compressor connected
well?
Correct the connection or
replace the wires and
connectors.
No
Is the IPM installed correctly ?
Correct the installation,
tighten the screws and
apply silicon grease.
No
IPM continuity check. Are the IPM
terminal resistance values uniform ?
Yes
Replace the IPM board or replace
the main PCB if the IPM board and
main PCB are integrated together.
No
Check if the outdoor fan runs
properly or the outdoor unit
ventilation is good.
Yes
No
Please refer to the solution of
【
Fan
Speed Has Been Out Of Control
】
malfunction
Yes
Are the compressor resistance
values uniform?
No Replace the compressor.
Yes
Replace the outdoor main PCB.
Check the reactor or
Inductance .Is it normal?
No
Replace the reactor
or Induct or
Yes
Yes