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/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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Related fault codes

cPView →

All 41 fault codes on the Concept 400 20 1 Mfs

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

01E02E03E04E05E06E08E09E10E11E14E15E16E17E18EAncPEr 12Er01Er02Er03Er04Er04+Er05Er05+Er06Er06+Er08Er08+Er09Er09+Er10Er14Er15Er16Er17Er17+RESETEr18L3LP

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