Emergency
306 V on Worcester Bosch Junior 24i

Your boiler is still detecting a flame even after it has been told to shut off the gas, which is a safety concern that prevents the unit from operating.

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 signal after closing the fuel supply – the air/gas ratio control valve might need replacing

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 →C6View →

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