Emergency
An 11 on Biasi Advance Plus 35C

Your boiler has detected a false flame signal inside when the burner is supposed to be switched off, which prevents it from operating safely.

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.

What the manual says

Manufacturer manual

Parasite flame

From this model's manual
Verified against the Biasi/Biasi Advance Plus Service 2012 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 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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Related fault codes

An 01View →An 02View →

All 25 fault codes on the Advance Plus 35C

Seeing a different code? Every code this model can display, in one place.

7169-016E01-204E01-205E23-792E83-101Er 01Er 02Er 03Er 04Er 05Er 06Er 07Er 08Er 09Er 10Er 11Er 14Er 99H58-661H58-709H74-550H74-553Li 01

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