BoilerFaultCodesYour boiler has shut down because the water inside the central heating system has reached an unsafely high temperature.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Central heating flow T° > 95°C
What causes this fault?
This fault occurs when water cannot move quickly enough through the boiler to carry heat away, causing the internal temperature to spike rapidly. The most common reasons are a failed internal pump that has stopped spinning or a physical blockage caused by a build-up of sludge and debris within the pipework.
This issue often surfaces during the first cold spell of autumn when the heating is turned back on after being idle all summer, which can cause internal pump parts to seize.
DIY fix possible
Check that all radiator valves are fully openEnsure the boiler pressure gauge is between 1.0 and 1.5 barSwitch the boiler off and back on again to reset the system after it has cooled down
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F14 — 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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