Low
dP on Biasi Concept 400 20 1 Mfs

Your boiler is currently in a manual testing mode used by engineers to check emissions, rather than experiencing a genuine breakdown.

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

Chimney sweep function step (same as cP on these models)

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 reset button on your boiler's control panel.Press and release the reset button once.Wait a few minutes for the boiler to return to its normal central heating or hot water operating mode.

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