BoilerFaultCodesYour boiler has switched itself off because the water inside the system has become too hot.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Temperature too high during central heating demand
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature limit because it isn't moving away from the heat exchanger properly. The most common reasons are a pump failure, a blockage caused by sludge and debris in the pipework, or air trapped within the system preventing flow.
This fault often appears during the first cold spell of autumn when the heating is turned back on after being idle for several months, which can cause internal pump parts to seize.
DIY fix possible
Check that at least two or three radiator valves are fully open to allow water to flow.Ensure there are no obstructions or trapped air by bleeding your radiators.Check your boiler pressure gauge and top it up to 1.5 bar if it is too low.
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A boiler cover plan would cover faults like F001 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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