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Taco SR502 with Weil Mclain Ultra

Im adding a zone with circulator pump to my boiler setup that includes a Weil Mclain Ultra 80 and a DHW. The DHW and boiler house zone are primary/secondary respectively.

The new zone is for radiant heat and I'm using a Taco SR502 for control since the boiler can only run 3 pumps. I have two main questions:

1) What diagram do I use for the wiring setup - Im specifically referring to the user manual for the SR502 panel. I don't see a basic setup for what I'm trying to do. I realize a 501 might have done the job but I got the 502 in case of expansion someday.

2) Will I be wiring the Taco control panel to the WM Ultra control panel? Im referring to the note "To: 'TT' on boiler" in the SR502 manual. Is there a particular setup for the taco panel to ultra boiler setup?



  • Paul48
    Paul48 Member Posts: 4,470

    TT refers to thermostat connections on  a boiler. The U-Control red terminal block provides for 3 thermostat connections.
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