Boiler makes loud banging or kettling noises when heating is on
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 down the boiler flow temperature and allow the system to cool if noises are severe. Do not ignore persistent banging as it can damage the boiler.
User checks:
- Reduce flow temperature: Set the central heating temperature to around 65°C.
- Bleed radiators: Remove trapped air and top up pressure.
- Check system filter valves: If you have an Ideal System Filter, ensure its isolation valves are fully open.
Engineer tasks: Powerflush or chemically clean the system, descale or replace the primary heat exchanger, clean the system filter, and check pump performance.
Repair Difficulty
Required Part
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