High
A Illuminated continuously on Alpha C23

Your boiler has attempted to start but is unable to ignite its internal flame, meaning your heating and hot water will not work.

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 has failed to 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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