Boiler trips the electrical circuit breaker or RCD when it tries to start
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: Repeated tripping indicates a potentially dangerous fault. Do not keep resetting the breaker.
User checks:
- Visual inspection: Look for obvious signs of water leaks around the boiler. If present, turn off water and power and call an engineer.
- Isolate boiler: Leave the boiler switched off at the fused spur and do not attempt further resets.
A qualified engineer or electrician must test insulation resistance of components, locate the short, and repair or replace the faulty part.
Repair Difficulty
Required Part
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