Boiler intermittently shuts down with E12, especially during hot water use at low flow rates.
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.
Possible Causes
How to Fix / Troubleshooting
Safety first: Turn off power and close the cold water inlet valve before removing the flow sensor.
User-level checks:
- Ensure that taps are fully opened when drawing hot water; very low flow may not trigger the boiler.
- Check that service valves under the boiler are fully open.
Technical checks (qualified personnel):
- Remove and inspect the DHW flow sensor/turbine for debris or scale; clean carefully and ensure the turbine spins freely.
- Clean or replace the cold inlet filter/strainer.
- Measure the sensor output (e.g. Hall effect pulses) during water flow and compare with specifications.
- Replace the flow sensor if no or erratic signal is detected.
After reassembly, check for leaks and verify that hot water starts reliably at normal tap openings.
Repair Difficulty
Required Part
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