Emergency
306 V on Worcester Bosch Greenstar 8000 Style GR8700iW 35 SB

Your boiler has detected that a flame is still present briefly after the gas supply has been shut off.

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/Worcester Bosch Greenstar 8000 Life System installation & service manual.
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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Related fault codes

EA 306View →305View →308View →

All 32 fault codes on the Greenstar 8000 Style GR8700iW 35 SB

Seeing a different code? Every code this model can display, in one place.

200201202203204208224227228305306815815 B1017 W1022 B1065 B1068 W1075 W1076 W2920 V2927 B2946 V2948 B2950 B2963 B2964 B2965 B2966 B2967 B2970 B2971 B

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