BoilerFaultCodesYour boiler has detected that the water inside is getting too hot and has shut down to prevent damage.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Temperature is too high during central heating demand.
What causes this fault?
This fault occurs when water cannot flow through the boiler quickly enough to carry heat away, causing the internal temperature to reach a dangerous level. The most common reasons are a failed pump that isn't pushing water around or a physical blockage, such as air or sludge, trapped within the main heat exchanger.
This fault often appears during the first cold spell of autumn when the heating is turned back on after a long summer break, which can cause internal pump components to seize.
DIY fix possible
Check that at least two of your radiator valves (TRVs) are turned to the highest settingEnsure your boiler pressure is between 1.0 and 1.5 bar on the displayTurn the boiler off and back on again at the mains to reset the system
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
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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