Fujitsu Waterstage WS G140DC6 Series Maintenance Document page 26

Split system (Single phase and 3-phase type)
Clear 24: Pressure sensor error
Hydraulic Unit LED: Green 8 flashes / Red 6 flashes
Outdoor Unit LED: 3 flashes
Probable causes:
Connector connection failure.

Pressure Sensor failure.

Main PCB failure.

Check:
1. Check connection of the Pressure Sensor:
- Check if the terminal connection is loose.
- Check if connector is removed.
- Check if connector is erroneous connection.
- Check if cable is open.
Upon correcting the removed connector or mis-wiring, reset the power.
2. Check output voltage of Main PCB :
Check voltage of Main PCB (Measure at Main PCB side connector)
1 pin(Red) - 3 pin(Black) DC5V +/- 5%
If the voltage is not correct, replace Main PCB.
3. Check output voltage of Pressure Sensor
Check voltage of Main PCB (Measure at Main PCB side connector)
2 pin(White) - 3 pIn(Black) Voltage is refer to the following graph.
Voltage [V]
If the voltage is not correct, replace Presure Sensor.
26
OK
PRESSURE SENSOR
OK
Pressure [MPa]
Maintenance Document 1544-1