Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Looking for Isolation relay converter module recommendation

Parachute Member Posts: 25
Anybody know where I can source a small isolation relay similar to this one: http://www.controlshvac.com/ADA-1-0-10V-relay-for-DDC-HVAC_p_58.html. I'm trying to energize 24vac from a no voltage end DHW circuit so that when the DHW circuit is closed I get 24vac out the other end of the relay switch.


  • SWEI
    SWEI Member Posts: 7,356
    How much current do you need to switch at 24 VAC? Is the transformer there already, or do you need that as well?
  • ratio
    ratio Member Posts: 3,605
    The relay you linked to is used to "convert" an analog output into a digital output, but it sounds like you have an unpowered end switch you want to use. You should be able to power the end switch from whatever xfrmr runs the system, or maybe something like this is what you're wanting?
  • Parachute
    Parachute Member Posts: 25
    edited October 2015
    Sorry I was not clear: I want the non-powered, normally open, isolated endswitch--when closed--to trigger another switch to provide 24VAC power from a transformer, just like in the diagram of that relay I provided a link to. I have the transformer.
  • SWEI
    SWEI Member Posts: 7,356
    Any of these will work if you have 120V available to power them:
    Caleffi ZSR101
    Taco SR-501
    Honeywell R8845U

    If you're going to use the 24VAC to power it, all you need is a relay (FDI RIBU1C -- or pretty much any small relay.)