Service Manual -
VMH 9/12/18/24 SU & VMH30/36S D Series
40
43
9.3.
9
Over voltage or too low voltage protection diagnosis and solution
(P1)
Error Code
P1
Malfunction conditions
An abnormal voltage rise or drop is detected by checking the
specified voltage detection circuit.
Possible
causes
●
Power supply problems
●
System leakage or block
age
●
PCB faulty
Troubleshooting:
P
N
Check the power supply.
Is it OK?
Stop the unit
Check the connections
and wires. Are they OK?
Correct the connections or
replace the wires
Check the voltage between
P and N. Is it OK?
Replace the IPM board
Check the reactor. Is it OK?
Replace outdoor main PCB
Replace the reactor
Remark:
Measure the DC voltage
between P and N port. The
normal value should be
around 310V.