BoilerFaultCodesYour boiler has sensed that it is getting too hot and has shut down as a safety precaution 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: Safety sensor fault – temperature too high, sensor short circuit or open circuit
What causes this fault?
This fault occurs when the boiler's internal temperature exceeds safe limits, triggering an emergency shutdown to protect the components. The most common reasons are a lack of water flow caused by a stuck pump or a blockage, though it can also be triggered if the sensors themselves have failed or developed a wiring fault.
This issue often surfaces when the heating is first turned on after summer, as internal pumps can seize up during long periods of inactivity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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