BoilerFaultCodesYour boiler has switched itself off because it got too hot and needs time to cool down before it can be restarted.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Go to section ‘J’: Allow to cool. Check continuity across thermostat terminals (should not be more than 1.5 ohm).
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe temperature limit, causing a safety sensor to cut the power. The most common reasons are a pump failure that prevents water from moving, or a buildup of debris and limescale that restricts flow through the heat exchanger.
This issue often appears when the heating is first turned on after summer, as the internal pump can seize up during long periods of inactivity.
DIY fix possible
Turn the boiler off and wait 20-30 minutes for it to cool down.Ensure all radiator valves (TRVs) are fully open to allow water to flow.Turn the selector switch to the 'Reset' position for at least 5 seconds, then back to the heating or hot water setting.
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A boiler cover plan would cover faults like Overheat thermostat operated (neon flashing) — 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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