Low
02 on Biasi Dina

Your boiler is currently running a manual test mode designed for engineers to check performance, and it is not a standard functional fault.

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 maximum DHW output (under P06)

From this model's manual
Verified against the Biasi Dina 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

Switch the boiler to the 'Off' or 'Standby' positionWait 30 secondsSwitch the boiler back to the 'On' or 'Winter/Summer' mode to exit the test sequence

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