A08
Riello
Flow NTC Sensor Failure
Boiler shows flow temperature sensor fault, may not start or may run erratically
Advertisements
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Advertisements
Possible Causes
Open-circuit or shorted NTC sensor, Damaged sensor wiring harness, Poor connection at control board, Water ingress into sensor pocket
How to Fix / Troubleshooting
Safety: Isolate power before accessing the control panel or sensors.
- Locate flow sensor: Identify the flow NTC sensor on the boiler flow pipe (usually clipped or inserted into a pocket).
- Check connections: Ensure the sensor plug is firmly seated on the PCB and that the cable is not damaged or pinched.
- Visual inspection: Look for signs of corrosion or water leakage around the sensor pocket. Any leak must be repaired before replacing the sensor.
- Reset and test: After checking connections, reset the boiler. If the error persists, the sensor is likely faulty.
- Replace sensor: With the system drained or pressure reduced as needed, remove the old NTC and fit a new Riello-compatible flow sensor, using thermal paste or sealing washers as specified.
Advertisements
Repair Difficulty
Medium
3/5
Required Part
Flow NTC Sensor
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements