Emergency
365 Fb on Worcester Bosch Greenstar CDi Compact

Your boiler has detected an internal safety issue with the gas control mechanism and has automatically shut down to prevent the fuel supply from operating incorrectly.

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

Gas valve EV1 leak test failed

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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