High
8.4.1 on Chaffoteaux Britony II 40FF

Your boiler is failing to ignite the gas burner, meaning you will not have any heating or hot water until it is reset or repaired.

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

Main burner does not light

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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