Low
Burner output modulates on Alpha CB 240 / 280

Your boiler is automatically adjusting its flame intensity to save energy and balance heat, which is a normal part of its efficient operation rather than a breakdown.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Follow section 'G' fault finding

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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