BoilerFaultCodesYour boiler has sensed that the water inside it is too cold and has switched on its safety mode to prevent the 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: Boiler protected by an automatic frost protection device (water temperature below 5°C)
What causes this fault?
This fault occurs when the temperature sensor inside your boiler detects that the water has dropped to near-freezing levels. It is a safety feature that triggers the burner to fire up automatically to warm the water and protect the internal components from expansion damage. The most common reason is that the boiler is located in a cold area like a garage or loft during a period where the heating has been left off.
This code is almost exclusively seen during the winter months or during sudden overnight cold snaps when external temperatures drop below freezing.
DIY fix possible
Ensure the boiler's electrical power supply remains switched onCheck that your gas supply is active so the boiler can fire up to warm the waterIncrease your room thermostat/timer settings slightly to encourage the system to runIf the condensate pipe is frozen outside, carefully pour warm (not boiling) water over it to defrost it
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