02 Low

Biasi 02 Fault Code

The Biasi 02 fault code means: your boiler is currently running a manual test mode designed for engineers to check performance, and it is not a standard functional fault.. It appears on 1 Biasi model in our database.

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.

Technical description: Activation of the chimney sweep function at maximum DHW output (under P06)
Typical repair cost £0-80 (including labour)

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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Biasi models that show the 02 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Biasi 02 fault code information on this page is sourced and cross-checked against the official Biasi service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026