BoilerFaultCodesYour boiler has switched itself off because it has started to overheat, usually due to a lack of water flow or 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: Safety Thermostat Activated
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature limit, causing a safety sensor to automatically shut the system down to prevent damage. The most common reasons are a pump failure that stops water from moving or a blockage in the pipes that prevents heat from leaving the main heat exchanger.
This issue often appears when the heating is first switched on after summer, as pump components can seize up during long periods of inactivity.
DIY fix possible
Check that your boiler pressure is between 1 and 1.5 bar on the gaugeEnsure all radiator valves and isolation valves are fully openRotate the selector switch to the 'Reset' position for at least five seconds
Find a Gas Safe engineer
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like 7 — no call-out fees, no surprises.
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Potterton Performa 24 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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