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38 FAULT CODE
Viessmann

Boiler Water Temperature Sensor Open Circuit

Medium Severity Engineer Required

The main boiler water temperature sensor cable has broken or become disconnected.

Step-by-Step Fix Guide

  1. Step 1

    Check the sensor cable connections

  2. Step 2 Engineer only

    Call a Gas Safe engineer to test and replace the sensor lead if broken

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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