BoilerFaultCodesYour boiler's internal computer has detected a problem while checking its own sensors and safety systems.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Self-test: The connected sensors are checked regularly by the boiler controller.
What causes this fault?
This fault occurs when the boiler's internal computer performs a routine safety check and notices that its sensors are sending back illogical or conflicting data. The most common reason is an electrical communication error between the main control board and the internal temperature sensors, often caused by a loose connection or a failing electronic component.
DIY fix possible
Locate the reset button on the boiler control panel.Press and hold the reset button for 2 seconds until the display changes.Wait for the boiler to restart and check if the code clears.
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A boiler cover plan would cover faults like 2 — 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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