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17.5.25 Outdoor High Pressure Protection (H98 / F95)
Malfunction Decision Conditions:
During operation of cooling / heating, when pressure 4.2 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 Dust accumulation in the outdoor unit heat exchanger.
5 Air short circuit at outdoor.
6 Faulty outdoor unit fan motor.
7 2/3 way closed.
8 Clogged expansion valve or strainer.
9 Excessive refrigerant.
10 Faulty outdoor high pressure sensor.
11 Faulty outdoor unit PCB (main).
Operation Mode
Check the system water pump.
Heating / Tank
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.
Troubleshooting:
For safety reason and to prevent component breakdown,
always switch off the power before remove and connect the component.
Caution