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Radiant DIY

JoshuaB Member Posts: 3
I have installed a radiant heat system. The boiler I chose is the Viessmann Vitodens 200-W Boiler B2HA-35. To control my three zones, I am using a Taco SR503.

I cannot figure out how to connect them so the Taco controls the Vitodens.

The Taco instructions refer to a "TT" connection on the boiler. The boiler instructions refer to a "remote" connection that is optional.

Also, the boiler instructions call for a rheostat that controls the temperature of the water with a 0-10 volt change. Is this necessary? If so, do I need to provide it voltage or simply install a rheostat between the leads?

Thanks in advance


  • Ironman
    Ironman Member Posts: 6,873
    The boiler does NOT come on from a demand signal from the SR503. It comes on based upon its ODR curve, water temp and parameter settings.

    I'd recommend you contact Veissman tech support or find a contractor who's trained on that boiler and knows it.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.
  • JoshuaB
    JoshuaB Member Posts: 3
    I'll try that route. Thanks