BoilerFaultCodesYour boiler has shut down for safety because it cannot maintain a steady pilot light or has detected a problem with how waste gases are being removed.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Indicates that the pilot light is not operating correctly, or the combustion products discharge safety device has been activated (lockout).
What causes this fault?
This fault occurs when the boiler's internal sensors detect that the pilot flame has gone out or that dangerous exhaust gases are not leaving the flue correctly. The most common reason is a worn-out sensor failing to detect the flame, though it can also be triggered if a blockage in the chimney or wind gust disrupts the burner.
This issue often appears during the first cold snap of autumn when the boiler is pushed to run for longer periods after being idle all summer.
DIY fix possible
Check if other gas appliances (like a cooker) are working to confirm gas supplyLocate the reset button (usually a small button or dial on the front panel)Press and hold the reset button for several seconds to try and reignite the pilot light
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