Boiler does not start at all, display is blank or unlit, no response from controls.
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: Before any checks, ensure the boiler's isolation switch is off. Electrical work must comply with local regulations.
User-level checks:
- Check that the boiler's fused spur or plug is switched on and that the fuse has not blown.
- Verify that the household circuit breaker for the boiler circuit has not tripped.
Technical checks (qualified personnel):
- Confirm presence of mains voltage at the boiler terminals.
- Check and replace internal fuses on the PCB with identical ratings if blown.
- Inspect the on/off switch and wiring block for loose connections or burning.
- If supply and fuses are correct but the boiler remains dead, replace the main PCB.
After restoring power, perform functional tests on heating and hot water.
Repair Difficulty
Required Part
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