BoilerFaultCodesYour boiler has switched itself off because it has detected that the water inside has become dangerously hot.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: SAFETY TEMPERATURE LIMITER
What causes this fault?
This fault occurs when the internal temperature of the boiler exceeds safe limits, triggering a safety shut-off to protect the system. The most common reason is a lack of water flow, often caused by a failing circulation pump or a blockage in the heat exchanger preventing heat from being carried away. In some cases, it can also be triggered by a faulty sensor giving an incorrect high-temperature reading.
DIY fix possible
Wait for the boiler to cool down completely (at least 20-30 minutes).Locate the reset button, typically found behind the small drop-down door or on the underside of the boiler.Press the reset button firmly; if the neon light goes out and the boiler restarts, monitor it closely.Ensure all radiator valves are open and the pump is running to prevent it happening again.
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
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