High
Lock-out signal lamp 6 on Biasi Garda HE MK2

Your boiler is trying to start but the flame is failing to ignite, causing it to shut down for safety precautions.

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

The boiler fails to light during the ignition attempt period. The full sequence control p.c.b. will go to lockout.

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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