Emergency
306 on Worcester Bosch Greenstar 8000 Life Regular

Your boiler has detected that a flame is still present even though it has commanded the gas to turn off, which indicates a potential safety issue with the shut-off system.

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.

What the manual says

Manufacturer manual

Flame signal after closing the fuel supply

From this model's manual
Verified against the Worcester Bosch Greenstar 8000 Life Regular installation & service manual, page 71.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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