41
S/N
Error Code
Symptom
Possible Cause
Solution
3
The LED indicator
of the unit displays
ER16 and the
wired controller
displays 16
Heat source
side pump/
cooling tower
fan overload
Over current of the pump, the overload
protector triggered.
Check whether the electric current parameter of
the overload protector is configured correctly by
referring to the wiring diagram.
Over current of the fan, the overload protector
triggered.
4
The LED indicator
of the unit displays
ER17 and the wired
controller
displays 17
Overload of
compressor
in #2
Over current in the compressor has triggered
the overload protector.
1. Check whether the electric current parameter
of the overload protector is configured correctly by
referring to the electric circuit.
2. Check whether the resistor of the malfunctioned
compressor meets specification requirements.
5
The LED indicator
of the unit displays
ER18 and the
wired controller
displays 18
Using side pump
overload
Over current in the pump has triggered the
overload protector.
Check whether the electric current parameter of
the overload protector is configured correctly by
referring to the electric circuit.
6
The LED indicator
of the unit displays
ER19 and the
wired controller
displays 19
Lack of
water flow of
evaporator
1. Pump is too small.
Replace the pump.
2. Blocked of water filter.
Clean water filter.
3. Air inside water system.
Discharge air by opening the pump.
4. water flow switch broken.
Replace water flow switch.
5. Water pressure drop to large, water system
is not balance.
Optimize the water system.
6. Blocked of other parts in water system.
Check and repair.
7
The LED indicator
of the unit displays
ER20 and the
wired controller
displays 20
High pressure
of #1
1. Heat exchanger dirty.
Check and troubleshoot.
2. Blocked of refrigerant filter.
Check and replace.
3. Water temperature too high (condenser).
Tune down the water temperature.
4. Lack of water (condenser).
Check and troubleshoot.
5. Blocked of water filter (condenser).
Clean the water filter.
6. Too much refrigerant.
Release a proper amount of refrigerant.
7. Failure of high-voltage modular output port. Replace the module.
8. The switch has broken down.
Replace the pressure switch.
8
The LED indicator
of the unit displays
ER21 and the
wired controller
displays 21
Low pressure
of #1
Malfunction of heat exchanger.
Check and troubleshoot.
Insufficient refrigerant or leakage .
Check and replenish refrigerant.
Failure of low-voltage modular input port .
Replace the module.
The low pressure sensor has broken down.
Replace the pressure sensor.
9
The LED indicator
of the unit displays
ER22 and the
wired controller
displays 22
Lack of
water flow of
condenser
1. Pump is too small.
Replace the pump.
2. Blocked of water filter.
Clean water filter.
3. Air inside water system.
Discharge air by opening the pump.
4. water flow switch broken.
Replace water flow switch.
5. Water pressure drop to large, water system
is not balance.
Optimize the water system.
6. Blocked of other parts in water system.
Check and repair.
10
The LED indicator
of the unit displays
ER24 and the
wired controller
displays 24
High pressure
of #2
1. Heat exchanger dirty.
Check and troubleshoot.
2. Blocked of refrigerant filter.
Check and replace.
3. Water temperature too high (condenser).
Tune down the water temperature.
4. Lack of water (condenser).
Check and troubleshoot.
5. Blocked of water filter (condenser).
Clean the water filter.
6. Too much refrigerant.
Release a proper amount of refrigerant.
7. Failure of high-voltage modular output port. Replace the module.
8. The switch has broken down.
Replace the pressure switch.
11
The LED indicator
of the unit displays
ER25 and the
wired controller
displays 25
Over-low
of water
temperature of
evaporator
The temperature of return water is set too low. Change the temperature setting for return water.
The water flow is too small, resulting in a large
pressure drop.
Check the water system.
