BoilerFaultCodesYour boiler has noticed the temperature is very cold and has automatically turned itself on to prevent the internal pipes from freezing.
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: Antifrost mode active
What causes this fault?
This occurs when the boiler's internal sensors detect that the water temperature has dropped below 5°C. To prevent the unit from freezing and potentially bursting a pipe, the boiler automatically fires up the burner and runs the pump until the water reaches a safer temperature. This is a normal safety feature designed to protect your heating system during extreme cold spells.
This status code is almost exclusively seen during the winter months when external temperatures drop below freezing.
DIY fix possible
No action is required; this is a normal safety function.The boiler will stop this mode automatically once the internal water temperature rises sufficiently.Ensure your external condensate pipe is not frozen if the weather is extremely cold.
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