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Wiring a Viessman Vitotronic 200 in conjunction with an existing 12 zone Taco system

TheJarman Member Posts: 2
edited May 2017 in Thermostats and Controls
I have just replaced a conventional oil fired boiler (that was controlled by an aquastat) with a new Viessmann Vitorond 100 and a Vitotronic 200 Control Unit.
Question is the aquastat on the old unit had T T inputs that were activated by the Taco relay firing the boiler on a demand for heat.

No such connection on the Vito 200 or the Pump Power Module.

The existing house has 9 Zones of radiant with mechanical mixing valves and 3 zones of hi cap baseboard with no mixing valves.

I do not want to redo the existing manifold and all of the circs along with the Taco relays....
How do I make everybody shake hands and play nice?

Also there is a boiler bypass with a circulator to inject supply water into the return header to keep the boiler from condensing. How do I control this circulator?



  • Ironman
    Ironman Member Posts: 7,225
    The 200 will operate off of its reset curve. No TT connection is necessary; it's a smart control.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • TheJarman
    TheJarman Member Posts: 2
    so no connection of any kind between the boiler controls and the taco relays?

    Thank you for the input.
  • Big Ed_4
    Big Ed_4 Member Posts: 2,541
    No need , the outdoor reset control will shut off the boiler when the outdoor temp rises to the set point ...
    I have enough experience to know , that I dont know it all
  • Big Ed_4
    Big Ed_4 Member Posts: 2,541
    Primary secondary piping .. There should be an connection in the control for the boiler circulator .. Size the circulator for was is recommended .
    I have enough experience to know , that I dont know it all