How much does it cost to fix Biasi error code Er 99?

Typical repair cost for the Biasi Er 99 fault is £80-160 including labour.

Er 99 High

Biasi Er 99 Fault Code

Q: What does the Biasi Er 99 fault code mean?

Your boiler’s internal computer has forgotten which model it is, meaning it has lost its configuration settings and cannot operate.

Also written as ER99 — same fault.

The Biasi Er 99 fault code means: your boiler’s internal computer has forgotten which model it is, meaning it has lost its configuration settings and cannot operate.. It appears on 2 Biasi models in our database.

Technical description: Boiler type not set (parameter P 01 value 00)

Typical repair cost £80-160 (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 Er 99 fault code

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

Advance 25C Repair: £60-250
Inovia 2020 Repair: £80-160

Source

Biasi Er 99 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