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D1 FAULT CODE
Ferroli

Diverter Valve Fault

Medium Severity Engineer Required

The diverter valve (which switches water flow between heating and hot water) appears to not be operating correctly.

Step-by-Step Fix Guide

  1. Step 1 Engineer only

    This almost always requires a Gas Safe engineer to inspect and replace the diverter valve

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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