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Taco Switching Relay

Can I apply 24VAC across the R & W terminals on the t-stat input connections as a demand?


  • Tim McElwainTim McElwain Member Posts: 3,570
    No if you do you

    will burn out the transformer in the relay. The connections to R and W have to be dry contacts such as thermostat, aquastat, or end switch on a zone valve.
  • EmpireEmpire Member Posts: 2,343
    Dry contacts...

    Tim, I think he means to jump out the terminals.  No, do not apply 24 vac, yes jump out or dry contacts like in your t-stat.  Board provides it own power so do not ad any other t-former.


    Mike T.
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