How much does it cost to fix Biasi error code 13?

Typical repair cost for the Biasi 13 fault is £100-£350 including labour.

13 High

Biasi 13 Fault Code

Q: What does the Biasi 13 fault code mean?

Your boiler has detected that the water is heating up too quickly or not circulating properly, causing the system to shut down to prevent overheating.

The Biasi 13 fault code means: your boiler has detected that the water is heating up too quickly or not circulating properly, causing the system to shut down to prevent overheating.. It appears on 4 Biasi models in our database.

Technical description: Delta T M-R > 40K.

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

DIY fix possible

Check that all radiator valves are fully openCheck that the boiler pressure is between 1.0 and 1.5 barEnsure there are no blockages in the system by bleeding your radiators

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Biasi models that show the 13 fault code

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

Source

Biasi 13 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