Low
F3 on Alpha Intec 50CS

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.

DIY fix possible

Wait for the boiler to finish its heating cycle; the code will disappear once it reaches a safe temperature.Ensure your thermostat is turned up slightly if the property is very cold.Verify that any external condensate pipes are not frozen or blocked.

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