BoilerFaultCodesYour boiler has paused operation because it believes the internal temperature is so low that the pipes are at risk of freezing.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Heating mode frost protection error
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the water temperature has dropped near freezing levels, triggering a safety pause to prevent pipe damage. The most common reason is that the boiler is located in a very cold area, like a garage or loft, and the frost protection system has been activated to protect the heat exchanger. It can also be triggered by a faulty temperature sensor sending an incorrect freezing signal to the main control board.
This fault is almost exclusively seen during periods of extreme winter weather or prolonged cold spells when external temperatures drop below freezing.
DIY fix possible
Check that the room thermostat and radiator valves are turned upEnsure the boiler's power supply is constant and has not been switched offIf the condensate pipe is outside, check if it is frozen and gently thaw it with warm waterWait 15-30 minutes for the boiler to warm up naturally before resetting
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