62
Installation and Maintenance
Service Manual
(9) Malfunction of Overcurrent Protection E5
Main detection points:
●
Is the supply voltage unstable with big fluctuation?
●
Is the supply voltage too low with overload?
●
Hardware trouble?
Malfunction diagnosis process:
5. Malfunction of Overcurrent Protection
Main detection points:
● Is the supply voltage too low with overload?
● Hardware trouble?
Malfunction diagnosis process:
no
no
no
no
yes
no
no
End
yes
Malfunction is
eliminated
Is the supply voltage unstable
with big fluctuation?
Start
Is the supply voltage too low
with overload?
The fan is abnormal? Fan
speed is too low or fan doesn’t rotate
Measure the
current of live wire on the main
board with a clamp ampere meter. Is the
current higher than the value of the
overcurrent protection?
Is there blockage inside
the system? (Filth blockage, ice plug,
greasy blockage, the cut off valve hasn’t been
opened completely)
Is the compressor running
abnormally? Is there abnormal sound or oil
leakage; is the temperature of the shell
too high, etc.?
Is the indoor / outdoor
heat exchanger dirty,or are the air inlet
and outlet blocked?
Normal fluctuation should be within 10 % of the
rated voltage on the nameplate
Malfunction is
eliminated
no
yes
no
yes
no
yes
no
no
no
yes
no
yes
no
yes
yes
yes
yes
yes
yes
yes
Malfunction is
eliminated
Malfunction is
eliminated
Malfunction is
eliminated
Malfunction is
eliminated
Malfunction is
eliminated
Malfunction is
eliminated
Adjust the supply voltage to maintain it within
normal range
Clean the indoor and outdoor heat exchangers
and remove the blockage of air inlet and outlet
Check the motor and reinstall the motor to have
the fan run normally
Replace the mainboard with the same model
Replace the compressor
Flush the heat exchangers with high pressure
nitrogen
Replace the mainboard with
the same model
