BoilerFaultCodesYour boiler has switched itself off because the water inside became too hot, likely due to 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: Operates if water flow rate is inadequate; requires manual reset by pushing in the 'reset' button.
What causes this fault?
This fault occurs when the water inside the boiler exceeds a safe operating temperature, triggering a safety shut-off to prevent damage. It is usually caused by a blockage in the system or a failing pump that is no longer moving hot water away from the heat exchanger quickly enough. In some cases, the internal sensor responsible for monitoring heat may have developed a fault and is providing an incorrect reading.
This issue often surfaces when the heating is first turned on after summer, as pump components can seize during long periods of inactivity.
DIY fix possible
Locate the manual reset button on the control panelFirmly push the reset button in to restart the systemCheck that all radiator valves are open and the pump is running
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A boiler cover plan would cover faults like Safety temperature limiter — no call-out fees, no surprises.
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Ideal Concord Super Series 4 is discontinued — time for a new one?
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