Low
cP on Biasi Concept 400 20 1 Mfs

Your boiler has been accidentally switched into a special testing mode used by engineers to check emissions, which forces it to run at its highest possible power.

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 is at maximum output in heating mode

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 test button on your boiler control panel.Press the button once to exit the testing mode.Restart the boiler to see if it returns to normal operation.

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