BoilerFaultCodesYour boiler has shut down because it has detected that the water inside is getting much too hot, which is usually caused by a circulation problem.
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 the water inside the boiler heats up too quickly or reaches an unsafe temperature, forcing the system to shut down for safety. The most common reason is a pump failure or a blockage that prevents water from moving through the pipes, causing the heat to build up in one spot rather than being distributed to your radiators.
This fault is frequently seen at the start of autumn when heating systems are turned on for the first time after summer, as pump components can seize during long periods of inactivity.
DIY fix possible
Check that your radiator valves are fully open to allow water to flow.Ensure your system pressure is topped up to between 1 and 1.5 bar on the gauge.Try resetting the boiler to see if the error clears once the water cools down.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F14 — no call-out fees, no surprises.
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