Daikin UWL-B5 Series Catalogue/Engineering Data page 47

S/N Error Code
The LED indicator
of the unit displays
48 ER67 and the
wired controller
displays 67
The LED indicator
of the unit displays
49 ER68 and the
wired controller
displays 68
The LED indicator
of the unit displays
50 ER69 and the
wired controller
displays 69
The LED indicator
of the unit displays
51 ER70 and the
wired controller
displays 70
The LED indicator
of the unit displays
52 ER71 and the
wired controller
displays 71
The LED indicator
of the unit displays
53 ER72 and the
wired controller
displays 72
The LED indicator
of the unit displays
54 ER78 and the
wired controller
displays 78
The digital pipe of
55 the unit displays
ERRO
46
Symptom
The heat exchanger needs cleaning (cooling). Check and troubleshoot the unit.
The electronic expansion valve is not opened
as expected (heating).
Discharge
temperature #3
The water temperature is too high.
is too high
Insufficient refrigerant or leakage.
TH3 temperature sensor is broken down.
The heat exchanger needs cleaning (cooling). Check and troubleshoot the unit.
The electronic expansion valve is not opened
as expected (heating).
Discharge
temperature #4
The water temperature is too high.
is too high
Insufficient refrigerant or leakage.
TH4 temperature sensor is broken down.
Low pressure sensor failure.
Refrigerant
leakage in #3
Insufficient refrigerant.
Low pressure sensor failure.
Refrigerant
leakage in #4
Insufficient refrigerant.
Three lines of the low pressure sensor is
incorrectly connected.
Low pressure
The low pressure sensor is shorted/ open.
sensor
malfunction of
The Low pressure sensor has broken down.
#3
There is something wrong with the test circuit
of the low pressure sensor in the control
module.
Three lines of the low pressure sensor is
incorrectly connected.
Low pressure
The low pressure sensor is shorted/ open.
sensor
malfunction of
The Low pressure sensor has broken down.
#4
There is something wrong with the test circuit
of the low pressure sensor in the control
module.
1. The Bin/Ain communication line of the
master unit has broken off.
Communication
2. One of the A/B communication lines is
failure for all
connected incorrectly.
slave units
3. The Bin/Ain port of the master unit has
broken down.
Dialing setting
Dialing setting error on the module.
error
Possible Cause Solution
Check and troubleshoot the electronic expansion
valve.
Change the setting for return water temperature (to
be performed by service personnel).
Replenish a proper amount of refrigerant.
see Item 26 in the table.
Check and troubleshoot the electronic expansion
valve.
Change the setting for return water temperature
(to be performed by service personnel).
Replenish a proper amount of refrigerant.
see Item 27 in the table.
Replace the low pressure sensor.
Add refrigerant.
Replace the low pressure sensor.
Add refrigerant.
Reconnect the connecting lines of the low
pressure sensor.
Repair or replace the lines of the low pressure
sensor.
Replace the low pressure sensor.
Replace the control module.
Reconnect the connecting lines of the low
pressure sensor.
Repair or replace the lines of the low pressure
sensor.
Replace the low pressure sensor.
Replace the control module.
Reconnect the communication line to the Bin/Ain
port and screw down the wire terminal.
Check the communication line.
Replace the control panel of the master unit.
According to the circuit diagram, complete the
dialing setting again.