BoilerFaultCodesYour boiler has shut down because it has detected that the water inside is getting too hot, which is often caused by a blockage or a pump failure.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Maximum temperature - Flow temperature T1 too high
What causes this fault?
This fault occurs when the water leaving the boiler exceeds its safe temperature limit, causing the system to shut down to prevent damage. It is usually caused by a failure in the circulation pump or a physical blockage within the internal pipework that stops heat from moving away from the burner. In some cases, a faulty sensor may also be incorrectly reporting that the water is overheating.
This issue is frequently seen when the heating is first turned on after summer, as the circulation pump can seize up after long periods of inactivity.
DIY fix possible
Check that all radiator valves are fully openCheck that the boiler pressure is between 1.0 and 1.5 barReset the boiler by turning the mode dial to the 'RESET' position for two seconds
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Ideal Response SE is discontinued — time for a new one?
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