High
23 on Biasi Antares Combi

Your boiler is unable to control the flame size properly because a key electronic connection to the gas control system has failed.

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.

What the manual says

Manufacturer manual

Gas valve modulator disconnected.

From this model's manual
Verified against the Biasi Antares Combi installation & service manual, page 13.
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 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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