Your boiler has detected very low temperatures and is running its internal systems 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: Antifrost mode on (burner and pump in operation).
DIY fix possible
Ensure your heating controls are set to a temperature that keeps the room above freezingEnsure no external taps or pipes are blocked or frozenWait for the indicator lights to clear once the internal temperature of the boiler rises
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A boiler cover plan would cover faults like 40 - 50 - 60 - 70 - 80 — no call-out fees, no surprises.
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Chaffoteaux Minima HE is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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