BoilerFaultCodesYour boiler has switched itself off because it has become too hot to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The boiler is fitted with an additional safety device, which shuts down the boiler in the event of the system or the boiler overheating. If the device operates, the Boiler Safety Overheat neon will illuminate and the boiler will shut down.
What causes this fault?
This fault occurs when the water inside the boiler reaches an unsafe temperature, triggering a safety switch to prevent damage. The most common reasons are a failed pump stopping water from circulating or a build-up of sludge and debris blocking the internal pipework. It can also be caused by a faulty internal sensor incorrectly reading the temperature.
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 the pump to seize.
DIY fix possible
Turn the boiler off and allow it to cool down for at least 30 minutes.Ensure all radiator valves are open and there is no air trapped in the system.Unscrew the small black cap on the front control panel and press the reset button firmly.
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A boiler cover plan would cover faults like Boiler Safety Overheat neon — no call-out fees, no surprises.
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