Emergency Lockout
FA on Worcester Bosch Greenstar 25 HE Combi

Your boiler thinks it still sees a flame even though the gas supply has been turned off, which is a safety conflict.

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

A flame is detected after the gas has been switched off.

What causes this fault?

This fault occurs when the boiler's sensors detect heat or a residual flame signal even though the gas valve has been commanded to close. The most common reason is a gas valve that is physically leaking or failing to shut tightly, or a faulty sensor/circuit board that is incorrectly 'seeing' a flame that isn't really there.

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.

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Related fault codes

EAView →F7View →FDView →

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