J01 High

Biasi J01 Fault Code

The Biasi J01 fault code means: your boiler is having trouble communicating with the digital control panel or thermostat, meaning it cannot receive the correct instructions to provide heating or hot water.. It appears on 1 Biasi model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Remote control communication error
Typical repair cost £90-250 (including labour)

DIY fix possible

Turn the boiler power off at the fused spur switch for 30 seconds and then back on to reset the connection.If you have a wireless thermostat, replace the batteries with high-quality new ones.Ensure the thermostat is within range of the boiler and has not been moved too far away.

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Biasi models that show the J01 fault code

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

Source

Biasi J01 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