BoilerFaultCodesYour boiler has detected very cold temperatures 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: The boiler is operating in frost mode
What causes this fault?
This occurs when the temperature sensor inside your boiler drops below 5°C, triggering an automatic safety cycle. The boiler fires up to circulate heat through its internal components to prevent water from freezing and damaging the pipes. Once the water temperature reaches a safe level, the code will disappear and the boiler will return to its normal state.
This status code is most common during the winter months or during overnight cold snaps when external temperatures drop significantly.
DIY fix possible
No action is required as this is a normal safety function.The boiler will stop this mode automatically once the water temperature inside the unit rises sufficiently.Ensure your external condensate pipe is not frozen if temperatures are extremely low.
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