01 Low

Biasi 01 Fault Code

The Biasi 01 fault code means: your boiler is currently running a special system test used by engineers and is operating at its lowest power setting.. 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 minimum output (under P06)
Typical repair cost £0-80 (including labour)

DIY fix possible

Wait approximately 15 minutes for the automated test cycle to finishTurn the boiler mode selector knob to 'Off' and back to 'Winter' or 'Summer' to reset the modePress the 'Reset' button if the screen does not return to normal temperature display

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Biasi models that show the 01 fault code

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

Source

Biasi 01 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