Low
LP on Biasi Concept 400 20 1 Mfs

Your boiler has been manually set to a special testing mode used by engineers to check its performance, rather than operating in its normal heating mode.

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 Bm Biasi Concept 400 20 1 Mfs 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 chimney sweep or service button on the control panelPress the button once to deactivate the functionIf the code remains, turn the boiler off at the power switch for 30 seconds and restart

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