High
93 on Alpha H25 Xtraflame

Your boiler has detected an issue with the flame sensor reading, meaning it cannot safely regulate the internal flame and has shut down to prevent damage.

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

Flame signal beyond limit - The flame signal is beyond the adjustment range required for a limited period of time

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

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