Emergency
306 on Worcester Bosch 1000

Your boiler has detected that a flame is still present even though it has tried to turn the gas supply off, which indicates a potential safety control issue.

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?

Unexpected flame detection

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

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