Boiler does not start at all, no display or lights
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: Do not open electrical enclosures unless you are competent. Isolate power before removing covers.
Steps to check:
- Verify that the mains isolator or fused spur near the boiler is switched on.
- Check the fuse in the fused spur (typically 3A) and replace if blown, ensuring the correct rating.
- Check the consumer unit for any tripped breakers and reset if appropriate.
- If power is present at the boiler but the display is dead, an internal fuse or the PCB may have failed and requires a professional to diagnose.
Warning: Repeatedly blowing fuses indicates a fault that must be investigated by an electrician or heating engineer.
Repair Difficulty
Required Part
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