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612 FAULT CODE
Ariston

Fan Speed Incorrect Measurement

High Severity Engineer Required

The fan speed sensor is giving an incorrect reading — fan speed cannot be confirmed as safe for operation.

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 speed sensor (tachometric circuit) and replace if faulty

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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