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zc and zr terminals

clammyclammy Member Posts: 1,996
i just attended a taco semair and they did go over that ,i have used them (*ZR ZC) from a triple aqaustat relay to a taco taco multi circ relay to cycle the circ off on low limit ,i would go to the taco site and check out there wiring diagrams they have about every possible to use there controls but the zc zc terminals are only a switch and once the jumper is removed the circ will not operate ,it seems the ra832a has no isolated end switch a easy solution is to just get another taco sr501 and switch out the board it will fit right into the honeywell box and the taco cover will also fit or just upgrade them with the proper sized taco sr500 series expandable circ relay and make some money and open them up to some other opiotions like reset and the other plug in opitions peace and good luck clammy


  • oil-2-4-6-gasoil-2-4-6-gas Member Posts: 641
    ZC and ZR contacts

    i have a customer with a weil mclain wtgo-4 they have 3 taco zones 2 seperate transformers --1 thermostat is conneted to -t-t 1 circ on c1 the other is a swithcing relay 832a no x-x terminal --the switching relay will turn on the other pump -but i need to shut it off with the low side of the L8124a and i need it to run to the high setting without energizer the other heating circ..-- can i power the swithcing relays-contact with zc and power zr to run to the high setting?
  • DickDick Member Posts: 60

    The info that comes with the TACO controls is pretty weak and could be better and more thorough, shouldn't have to get on the internet or experiment on your own to get the proper control sequence.

    Plug in the OA reset option and it changes the operation of the ZR and ZC contacts, the literature seems to miss mentioning this.

    Better more thorough info = more control sales.

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  • John@Reliable[email protected] Member Posts: 171
    How many pumps?

    IF you have just one pump, you don't really need a pony relay at all. If you have two pumps I would check into a ZV control panel.
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