How much does it cost to fix Biasi error code 26 +?

Typical repair cost for the Biasi 26 + fault is £120-250 including labour.

26 + High

Biasi 26 + Fault Code

Q: What does the Biasi 26 + fault code mean?

Your boiler has shut down because its internal temperature sensors are giving very different readings, suggesting a circulation problem or a failing component.

Also written as 26 — same fault.

The Biasi 26 + fault code means: your boiler has shut down because its internal temperature sensors are giving very different readings, suggesting a circulation problem or a failing component.. It appears on 4 Biasi models in our database.

Technical description: Maximum deviation fault between the 2 heating NTC probes.

Typical repair cost £120-250 (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 26 + fault code

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

Source

Biasi 26 + 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