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S.21 FAULT CODE
Vaillant

DHW Mode — Fan Starting

Low Severity DIY Check Possible

Status code: Fan starting for domestic hot water cycle. Normal status.

Step-by-Step Fix Guide

  1. Step 1

    No action required

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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