Low
F3 on Alpha Intec 28GS

Your boiler has automatically activated its internal heater to protect itself from freezing during cold weather.

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

Anti-freeze mode in progress. Boiler operating to restore the minimum safety temperature against boiler freezing.

Engineer required

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

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