High
8.4.2 on Chaffoteaux Britony II 40FF

Your boiler is starting to heat water but quickly shuts down the flame, meaning you will likely have cold or flickering water temperatures.

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

Burner goes out on hot water demand

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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