High
21 on Biasi Antares Combi

Your boiler has stopped working because its internal safety computer cannot correctly control the gas valve, meaning the boiler has locked itself out for safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

EVG lockout (valve control Relay Failure).

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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