High
Lock-out signal lamp on Biasi Garda HE MK2

Your boiler has detected a potential safety issue and has shut itself down to prevent damage or danger.

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

This indicates that the safety lock-out has stopped the boiler. To re-start the boiler, it is necessary to press the boiler reset button 7.

From this model's manual
Verified against the Biasi Garda He Mk2 installation & service manual.
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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