Panasonic WH-ADC0916G9E8, Service Manual, Page: 124 / 205

124
17.5.16 Outdoor High Pressure Protection (H98)
Malfunction Decision Conditions:
During operation of heating, when pressure 4.0 MPa and above is detected by outdoor high pressure sensor.
Malfunction Caused:
1 Faulty water pump.
2 Insufficient water flow rate in system.
3 Water leak in system.
4 2/3 way closed.
5 Clogged expansion valve or strainer.
6 Excessive
refrigerant.
7 Faulty outdoor high pressure sensor.
8 Faulty outdoor unit PCB (main).
Troubleshooting:
For safety reason and to prevent component breakdown,
always switch off the power before remove and connect the component.
Check the system water pump.
Check the 2/3 way valve.
Is the 2/3 way valve closed?
Check for clogged expansion
valve or strainer.
Is the expansion valve or
strainer clogged (ice formed)?
Check refrigerant amount.
Is the additional refrigerant
amount filled correctly?
Yes
Yes
Yes
Yes Yes
Yes
No
No
No
No
No
No
Yes
Is the water pump working?
Check the system water
flow rate.
Is there any water leakage?
Check the system water passage.
Is the water pump speed
adjusted according to system
hydraulic external static pressure?
- Replace the expansion
valve and/or strainer.
- Reclaim and recharge
refrigerant.
- Replace the outdoor unit
PCB (main).
- Replace the outdoor high
pressure sensor.
Reclaim and recharge with
correct amount of
refrigerant.
Replace the faulty water
pump.
Open the 2/3 way valve.
Readjust the water pump
speed.
Fix the system water
leakage.