Part 5 – Diagnosis and Troubleshooting
5.26 Pd Troubleshooting
Digital display output
Procedure
Pd: High temperature protection of air side
heat exchanger temperature(T3)
The fan or fan motor is blocked or damaged
Ensure the fan or fan motor works
normally
The air side heat exchanger dirty or blockage
Clean the air side heat exchanger
The location of heat pump is near the place
where temperature is too high or with poor
ventilation
Make sure heat pump is away from high
temperature heat source and installed
with good ventilation
Air side heat exchanger temperature sensor is
not installed
Installed the air side heat exchanger
temperature sensor
Air side heat exchanger temperature sensor
1
connection on main PCB is loose
Ensure the sensor is connected properly
Air side heat exchanger temperature sensor is
affected by moisture or water
Air side heat exchanger Temperature sensor has
short-circuited or failed or big temperature drift
Notes:
1. Air side heat exchanger temperature sensor (T3) connection is port CN6 on the refrigerant system PCB.