BoilerFaultCodesYour boiler has detected that it is getting too hot or that water isn't moving through the system correctly, causing it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Sensor error, temperature fault or flow fault.
What causes this fault?
This fault occurs when the internal sensors detect that the water temperature inside the boiler has exceeded safe limits, triggered by a lack of circulation. The most common reasons are a failed pump that isn't pushing water around the system, or a blockage caused by a build-up of debris or air. In some cases, the sensors themselves may have become faulty and are providing an incorrect reading to the control board.
This issue often surfaces when the heating is first turned on after summer, as the pump can seize up during long periods of inactivity.
DIY fix possible
Check that your radiator valves are openEnsure your system water pressure is between 1 and 1.5 bar on the gaugeReset the boiler by turning the selector switch to 'R' for five seconds
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A boiler cover plan would cover faults like 1 red flash — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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