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Everything You Need to Know About Relays

HeatingHelp Administrator Posts: 634
edited September 2021 in THE MAIN WALL
Everything You Need to Know About Relays

A relay is just a switch. The purpose of any switch is to turn something on and off. A relay turns HVAC equipment on or off. It’s that easy.

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  • geno907
    geno907 Member Posts: 12
    In a situation for an oil boiler. Would you wire a relay and an aquastat together? If so, would line voltage go the the boiler's kill switch, then to the aquastat, then to a relay switch, then to the primary/zone controls/pumps? thanks.
  • Jamie Hall
    Jamie Hall Member Posts: 22,877
    Why do you need a relay at all, @geno907 ? What would be powering it on or off? And what, in turn, would it be turning on or off? Is there a reason the two circuits need to be separate (there sometimes are very good reasons, but you need to know why you are doing it).
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England