BoilerFaultCodesYour boiler is sensing a flame even though the gas should be turned off, leading the system to shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flame detected after gas. Gas valve switched off. Cables and connections to gas valve. Condensate trap. Flue (for blockages). Otherwise replace control board.
What causes this fault?
This fault occurs when the boiler's internal sensors continue to detect a flame or electrical current even after the gas valve has been instructed to close. The most common reason is a faulty gas valve that is failing to shut off properly or a 'ghost' signal caused by a malfunctioning control board or dampness around the electrodes. Because the system thinks a fire is still burning when it shouldn't be, it shuts down immediately to ensure your safety.
This fault can occasionally be triggered during periods of heavy rain or high humidity if moisture causes a short circuit in the electrical connections or blockages in the flue.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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