How much does it cost to fix Biasi error code 3 +?

Typical repair cost for the Biasi 3 + fault is £100-£350 including labour.

3 + High

Biasi 3 + Fault Code

Q: What does the Biasi 3 + fault code mean?

Your boiler has shut down completely because it detected a general operating fault and requires a manual reset to attempt to restart.

Also written as 3 — same fault.

The Biasi 3 + fault code means: your boiler has shut down completely because it detected a general operating fault and requires a manual reset to attempt to restart.. It appears on 2 Biasi models in our database.

Technical description: Generic lockout.

Typical repair cost £100-£350 (including labour)

DIY fix possible

Locate the selector switch on the front control panel.Turn the dial to the 'R' (Reset) position for five seconds.Return the dial to the 'On' or 'Winter' position and see if the boiler fires up.

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Biasi models that show the 3 + fault code

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

Source

Biasi 3 + 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