Daikin UWL-B5 Series Catalogue/Engineering Data page 42

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