Emergency Lockout
306 on Worcester Bosch Greenstar 8000 Life/Style

Your boiler is still detecting a flame even though it has tried to shut off the gas supply, 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 signal after closing the fuel supply

What causes this fault?

This fault occurs when the boiler's internal sensor detects a flame or an electrical current that looks like a flame even after the gas has been told to turn off. The most common reason is a gas valve that hasn't fully closed or an ignition electrode that is sending a false signal back 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.

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