How much does it cost to fix Biasi error code E89?

Typical repair cost for the Biasi E89 fault is £280-550 including labour.

E89 High

Biasi E89 Fault Code

Q: What does the Biasi E89 fault code mean?

Your boiler's electronic brain is struggling to process the incoming electrical power properly or has developed an internal hardware fault.

The Biasi E89 fault code means: your boiler's electronic brain is struggling to process the incoming electrical power properly or has developed an internal hardware fault.. It appears on 2 Biasi models in our database.

Technical description: Internal error (usually hardware) or problems with the mains electrical supply (excessive distortion of waveform).

Typical repair cost £280-550 (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 E89 fault code

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

Source

Biasi E89 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