Panasonic WH-SXC16F9E8 Service Manual page 105

16.5.13 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).
105