Panasonic WH-MHF09G3E5 Service Manual page 122

16.5.38 Cooling High Pressure Overload Protection (F95)
Malfunction Decision Conditions:
During operation of cooling, when pressure 4.0MPa and above is detected by outdoor high pressure sensor.
Malfunction Caused:
1 Dust accumulation in the outdoor unit heat exchanger.
2 Air short circuit at outdoor unit.
3 2 way valve closed.
4 Faulty outdoor unit fan motor.
5 Clogged expansion valve or strainer.
6 Excessive refrigerant.
7 Faulty outdoor high pressure sensor.
8 Faulty outdoor unit PCB (main).
Troubleshooting:
Check the dust accumulation on the
outdoor unit heat exchanger.
Is the outdoor unit heat
exchanger dirty?
No
Check the outdoor air
passage.
Is there any short circuit?
No
Check the 2 way valve.
Is the 2 way valve closed?
No
Yes
Clean the heat exchanger.
Yes
Provide sufficient air
passage
Yes
Open the 2 way valve.
For safety reason and to prevent component breakdown,
always switch off the power before remove and connect the component.
Check the outdoor unit fan
motor operation.
Is the outdoor unit fan
motor operate normally?
Yes
Check for clogged
expansion valve or strainer.
Is the expansion valve or
strainer clogged (ice formed)?
No
Check refrigerant amount.
Is the additional refrigerant
amount filled correctly?
Yes
122
Replace the outdoor unit
No
fan motor and/or outdoor
unit PCB (main).
- Replace the expansion
Yes
valve and/or strainer.
- Reclaim and recharge
refrigerant.
Reclaim and recharge with
No
correct amount of
refrigerant.
- Replace the outdoor unit
PCB (main).
- Replace the outdoor high
pressure sensor.