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zoning second loop

css Member Posts: 1
Hi, new to forum. I have a Weil Mclain cga-4 boiler running a single series loop baseboard heating system. I am in the process of installing a second zone. I will be using circulators as opposed to zone valves. I  have done all the heat loss calculations and know that the boiler will be fine(in size). My problem is that I am having a heck of a time figuring out the wiring side of the install(this is usually one of my strong points). I just cant seem to understand how to wire the t-stat, new pump, and boiler together with the current installed pump and tstat. I understand the tstat will be wired to the new pump controll relay to turn the pump on but from there I cant figure out how to make the boiler fire. Any help/advice would be appriciated. The simpler the explanation the better. Thanks in advance

Chad S


  • JStar
    JStar Member Posts: 2,752
    edited October 2010
    RA832A Switching Relay

    If you use an RA832A, you will wire the pump as usual, run the thermostat to T+T, and wire the boiler circuit to the dry contacts X+X for a 24 volt burner, or the number 4 (I think it;s 4) contact for a 120 volt burner.
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