Emergency Lockout
FA on Worcester Bosch Greenstar 25Si

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

Flame detected after gas valve shut off

What causes this fault?

This fault occurs when the boiler's internal sensors continue to detect a flame even though the gas valve has been told to close. The most common reason is a gas valve that is physically stuck open or leaking, though it can also be caused by a damaged circuit board sending incorrect signals or a faulty sensor carbon-tracked with soot.

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 →

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