High
8.13 on Chaffoteaux Britony II 40FF

Your boiler is making a loud knocking or vibrating noise because the water isn't flowing through the main heat exchanger correctly, causing it to overheat locally.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Heating Body Noise

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

8.11View →8.12View →8.14View →

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