BoilerFaultCodesYour boiler has become too hot and has shut itself down as a safety precaution.
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 - The boiler has overheated. Turn selector to the reset position R and hold for at least 2 seconds.
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature limit, triggering a safety sensor to cut the power. The most common reasons are a pump failure that stops water from moving or a blockage in the internal pipework that traps heat inside the heat exchanger.
This issue often surfaces when the heating is first turned on in autumn, as the pump can seize up after being inactive over the summer months.
DIY fix possible
Check that all radiator valves are fully open to allow water to circulateEnsure there is enough water pressure in the system (check the gauge reads at least 1 bar)Turn the selector switch to the 'R' position for at least 2 seconds to reset the boiler
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
A boiler cover plan would cover faults like neon illuminated (thermometer symbol) — 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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