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weil mclain wiring

Hey Carol, was wondering if you could answer a couple of questions for me, i am going to install a weil mclain ultra 80 boiler along with a weil mclain indirect fired water heater, and 4 baseboard zones, i am going to use a weil mclain wmcr-6 circulator zone controller with prioity, i was wondering if i should wire the indirect heater to the zone controller as priority, or wire the indirect heater to the control board on the boiler. Also would you know where i would have to land the wires from the circulator zone controller to the boiler control? thanks for imput....


  • Josh_10
    Josh_10 Member Posts: 787

    The Weil-Mclain Ultra tank will only wire to the boiler. It actually uses a resistor in the tank to fire the boiler. Also the boiler has efficiency algorithms built in to the unit.

    Additionally you will most likely want to use the outdoor reset feature which will change the supply temp to your heating system based on outdoor conditions. This will give you the best efficiency then when the indirect needs heat it ramps up the heat to the water heater only.
  • Empire_2
    Empire_2 Member Posts: 2,343
    Just a thought

    Don't forget to pipe Primary/Secondary.....

    Mike T.
  • Tony_23
    Tony_23 Member Posts: 1,033
    Wiring an Ultra

    The indirect should be wired to the boiler's terminal strip, just as Josh stated.

    The other wiring connection locations are pointed out in a book called The Installation Manual. It's a good idea to use it...
  • Glenn Sossin_2
    Glenn Sossin_2 Member Posts: 592

    will be provided by the MCBA board when it sees a demand across the DHW terminals. It will also bypass the ODR curve this way and ramp up the boiler to the DHW setting what ever you have it at.

    Good luck

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