44
11. Trouble shooting
S/
N
Fault description
Possible cause
Troubleshooting
Remarks
1
Too high
exhaust
pressure
1.Air or non-condensable gas found in the system Discharge and empty, if necessary, the
non-condensable gas
Cooling/heating
2.High suction pressure
Refer to “High Suction Pressure"
Cooling/heating
3.Undesirable high-pressure switch
Replace the high-pressure switch
Cooling/heating
4.Dirty or clogged fin of the condenser
Clean the air-side heat exchanger
Cooling
5.Insufficient air capacity or faulty fan of the
condenser.
Check the fan
Cooling
6.High charge of refrigerant
Adjust the charge of refrigerant
Cooling
7.High ambient temperature
Inspect the ambient temperature
Cooling
8.Insufficient water flow
Check the water flow
Heating
9.Water-side heat exchanger scaling or with
foreign matters inside
Clean up the incrustation scale
Heating
10.High outlet temperature of water-side heat
exchanger
Check the water temperature
Heating
2
Low suction
pressure
1.Insufficient refrigerant
Adjust the charge of refrigerant
Cooling/heating
2.Undesirable low-pressure switch
Replace the low-pressure switch
Cooling/heating
3.Insufficient water flow
Check the water flow
Cooling
4.Low water inlet temperature at water side
Check the water temperature
Cooling
5.Water-side heat exchanger scaling or with
foreign matters inside
Clean up the incrustation scale
Cooling
6.Insufficient air capacity
Check the fan
Heating
7.Short circuit found in air circuit
Check the cause of short circuit and take
troubleshooting
Heating
8.Incomplete defrosting
Replace the poor 4-way valve or defrosting
sensor
Heating
3 Too low exhaust
pressure
1.Lack of refrigerant
Adjust the charge of refrigerant
Cooling/heating
2.Low suction pressure
Refer to “Low Suction Pressure"
Cooling/heating
3.Low ambient temperature of air-side heat
exchanger
Check the ambient temperature
Cooling
4.Too low water temperature at water side
Check the water temperature
Heating
4
1.Too high charge of refrigerant
Adjust the charge of refrigerant
Cooling/heating
High suction
pressure
2.High water inlet temperature at water side
Check the water temperature
Cooling
3.High ambient temperature of air-side heat
exchanger
Check the ambient temperature
Heating
5
Overtemperatur
e of exhaust
temperature
sensor
1.Poor ventilation around the unit
Clean up the obstacles around the unit, or
add air ducts
Heating
2.Too low ambient temperature
Shut down
Heating
3.Dirty or clogged filter at fluorine side
Replace the filter
Cooling/heating
4.Incomplete frosting (for heating) or no frosting
Change the frosting parameters
Heating
6
Open circuit or
short circuit of
temperature
sensor
1.Damaged sensor
Replace the sensor
Cooling/heating
2.Poor connection of sensor
Reconnect the sensor
7 Abnormal noise
1.Loose metal plate bolts
Retighten bolts
2.Liquid impact due to entry of liquid refrigerant
into the compressor
Adjust the charge of refrigerant or the poor
throttling device
Cooling/heating
3.Poor compressor
Replace the compressor