Heat Pump, Split System, Single Service, 3 phase
Maintenance Document 1394-1 35
Clear 12: Heat-exchange thermistor (intermediate) error
Hydraulic Unit LED:
Green 7 flashes / Red 3 flashes
Outdoor Unit LED: 5 flashes
Probable causes:
• Misconnection.
• Sensor failure.
• Main PCB failure.
Check:
1. Check the sensor connection:
- See if the connector has been disconnected.
- 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) -10 -5 0 10 15 20 25 30
Resistance (kΩ) 27,5 20,9 16,1 12,4 9,73 7,67 6,10 3,95
- 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)
- If there is no voltage, replace Main PCB.
OK
OK