Emergency
2923 on Worcester Bosch Greenstar 28CDi

Your boiler has detected an issue with how the gas supply is being controlled, so it has safely shut itself down to prevent any risk.

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

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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Related fault codes

2924View →2925View →

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