Er 05 + High

Biasi Er 05 + Fault Code

Also written as ER05 — same fault.

The Biasi Er 05 + fault code means: your boiler has detected a problem with the fan that safely removes exhaust gases, meaning the system has shut down for safety.. It appears on 2 Biasi models in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Faulty fan control system
Typical repair cost £200-£450 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Biasi models that show the Er 05 + fault code

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

Source

Biasi Er 05 + 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