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Robert ChurchJul 25, 2025
What to do if my Viessmann VITOTRONIC 100 Control Unit boiler is cold and the burner isn't running?
- KKara WilsonJul 25, 2025
If your Viessmann Control Unit boiler is cold and the burner isn't running, here are a few things you can check: * The high limit safety cut-out may have responded. In this case, reset the high limit safety cut-out. * There may be a problem with external safety equipment. Check the connection and the external safety equipment itself. * There may be a problem with Vitotrol 100. Check the connection and Vitotrol 100. If necessary, insert a jumper across control unit terminals 9 and 10. * The MCB F1 may have responded. Check the connections and the burner, and replace the fuse if needed. * The burner may be in a fault state. Check the burner.