BoilerFaultCodesYour boiler is struggling to move water around the system properly, which is causing it to overheat and shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: All Boilers
What causes this fault?
This fault occurs when the water inside your boiler is heating up too quickly because it isn't being pumped away fast enough. The most common reasons are a pump that has seized up, a build-up of sludge blocking the pipework, or a blockage inside the main heat exchanger.
This issue is more frequent in autumn when the heating is turned back on for the first time, as pump components can seize up after being idle during the summer.
DIY fix possible
Check that your system pressure is between 1 and 1.5 bar on the pressure gauge.Ensure all radiator valves are fully open to allow water to flow.Try bleeding your radiators to remove trapped air that might be blocking circulation.
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 1p2 — 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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