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.

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

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

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

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Work through these before the call-out.

Safety-critical — turn off, read this.

7 signs repair isn't worth it anymore.