Emergency Lockout
FA on Worcester Bosch CDi Classic

Your boiler is still detecting a flame even after it has been told to shut down, which indicates a potential safety issue with the gas supply inside the unit.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Flame detected after gas shut off – the gas valve needs checking – hire a Gas Safe installer.

What causes this fault?

This fault occurs when the boiler's internal sensors continue to detect a flame even though the system has commanded the gas supply to stop. The most common reason is a gas valve that hasn't closed fully or a faulty sensor sending an incorrect signal to the main control board.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer
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Related fault codes

EAView →FDView →F7View →

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