BoilerFaultCodesYour boiler has shut down because it has reached a temperature that is too high, often due to a lack of water or a circulation issue.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Primary Overheat fault (water pressure, pump, sensor, or thermostat).
What causes this fault?
This fault occurs when the water inside the boiler gets too hot too quickly, triggering a safety switch to prevent damage. The most common reasons are a pump that has stopped moving the water around, a blockage in the pipework, or a sensor that is sending incorrect readings to the control board.
This issue is more frequent in autumn or winter when the heating is first switched on after a long summer break, as pumps can often seize up from lack of use.
DIY fix possible
Check the pressure gauge and top up to 1.5 bar if it is lowEnsure all radiator valves are open to allow water flowPress the reset button once the boiler has cooled down
Find a Gas Safe engineer
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A boiler cover plan would cover faults like FAIL POINT G — no call-out fees, no surprises.
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Worcester Bosch 25si and 28si 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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