BoilerFaultCodesYour boiler has detected that the water temperature has got 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: Go to section 'B'
What causes this fault?
This fault occurs when the water inside the heat exchanger reaches a dangerously high temperature, triggering a safety switch to cut the power. It is usually caused by a lack of water flow, often due to a failed internal pump or a blockage in the system preventing the heat from escaping. In some cases, the thermostat itself may have become faulty and is reporting an incorrect temperature reading.
This issue often surfaces during the first cold snap of autumn when the heating is turned on after being idle all summer, which can cause internal parts like the pump to seize.
DIY fix possible
Wait for the boiler to cool down completely (at least 20 minutes)Turn the selector switch to the 'Reset' position and hold for 5 secondsTurn the selector switch back to the 'Hot Water' or 'Heating' positionCheck that your radiator valves are open and the system pressure is between 1 and 1.5 bar
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A boiler cover plan would cover faults like neon flashing — no call-out fees, no surprises.
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Potterton Performa 30 HE is discontinued — time for a new one?
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