Low
LP on Biasi Activ A

Your boiler has been accidentally switched into a specific testing mode used by engineers to check emissions, which prevents it from heating your home normally.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Activation of the chimney sweep function at minimum output

From this model's manual
Verified against the Biasi Activ A 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.

DIY fix possible

Locate the control panel on the front of your boiler.Look for a button or setting labeled 'Chimney Sweep' or indicated by a chimney icon.Press or toggle this button to deactivate the mode and return the boiler to its normal operating state.

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