Fujitsu WATERSTAGE WOYG160LJL Maintenance Document page 20

Clear 14: Expansion valve thermistor error
Hydraulic Unit LED:
Outdoor Unit LED:
Probable causes:
• Misconnection.
• Sensor failure.
• Main PCB failure.
Check:
1. Check the sensor connection:
-
See if the connector has been removed
-
See if the connection is correct
-
Check for any damage on the sensor cable.
After solving the misconnection problem, switch the heat pump back on.
2. Remove the sensor and check its resistance value :
- Check the resistance value.
Temperature (°C)
Resistance (k )
Temperature (°C)
Resistance (k )
- If the thermistor is faulty, replace it.
3. Check the electronic board voltage:
- Make sure circuit diagram of outdoor unit and check terminal voltage at thermistor (DC5.0V)
THERMISTOR
(COMPRESSOR)
THERMISTOR
(OUTDOOR)
THERMISTOR
(PIPE)
THERMISTOR
(DISCHARGE)
THERMISTOR
(HEAT SINK)
THERMISTOR
(PIPE MID)
THERMISTOR
(EXPANSION)
- If there is no voltage, replace Main PCB.
- 20 -
Green 7 fl ashes / Red 8 fl ashes
6 fl ashes
OK
0 5 10 15
168 130 101 79
60 70 80 90
12,3 8,7 6,3 4,6
OK
20 30 40 50
63 40 26,3 17,8
100 120
3,4 2
Waterstage / Maintenance Manual / 2105 - EN