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E4 FAULT CODE
Biasi

Fan Fault / Air Pressure Switch

High Severity Engineer Required

The fan is not operating correctly or the air pressure switch is not confirming airflow.

Step-by-Step Fix Guide

  1. Step 1

    Turn off the boiler

  2. Step 2 Engineer only

    Call a Gas Safe engineer to test the fan and air pressure switch

Gas Safe Reminder

Work on gas appliances must be carried out by a Gas Safe registered engineer. The steps above cover safe checks a homeowner can perform - any internal component replacement requires a qualified professional. If in doubt, always call an engineer.

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