Emergency
357 on Worcester Bosch Greenstar 4000

Your boiler has detected that the flame is remaining lit even after it has attempted to shut off the gas supply.

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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