ON Low

Biasi ON Fault Code

The Biasi ON fault code means: your boiler is operating normally and is currently responding to a request for heating or hot water.. 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: Boiler ON condition (function control in C.H. or D.H.W. position).
Typical repair cost £0 (including labour)

DIY fix possible

Check your thermostat or programmer to see if they are calling for heatRun a hot tap to see if the boiler responds normallyNo action is required as this is a status indicator, not a fault code

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Biasi models that show the ON fault code

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

Source

Biasi ON 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