Emergency
306 on Worcester Bosch Greenstar 8000 Style

Your boiler has detected that it is still sensing a flame even though it has tried to shut off the gas supply, which could indicate a safety issue with internal components.

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

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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