How much does it cost to fix Biasi error code 6 +?

Typical repair cost for the Biasi 6 + fault is £90-160 including labour.

6 + High

Biasi 6 + Fault Code

Q: What does the Biasi 6 + fault code mean?

Your boiler has detected that a temperature sensor responsible for tracking the water leaving the unit has stopped working correctly, and it has likely shut down to prevent overheating.

Also written as 6 — same fault.

The Biasi 6 + fault code means: your boiler has detected that a temperature sensor responsible for tracking the water leaving the unit has stopped working correctly, and it has likely shut down to prevent overheating.. It appears on 2 Biasi models in our database.

Technical description: NTC heating delivery probe failure.

Typical repair cost £90-160 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Biasi models that show the 6 + fault code

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

Source

Biasi 6 + 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