Emergency
2923 on Worcester Bosch Greenstar 4000

Your boiler has detected an issue with the internal gas supply component and has shut itself down to keep you safe.

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

Boiler electr. system fault - Unexpected feedback from the modulating/current controlled gas valve.

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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