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Hot water and steam

It's really not difficult. You will need a circulator relay with a second set of contacts, and an aquastat. Mount the aquastat in a boiler tapping below the water line and use the second set of relay contacts to operate the burner directly. When the hot water zone is calling for heat, the burner will heat the water up to the setting on the aquastat and shut off before making steam. Set the aquastat at 200 degrees or less.


  • Michael_23
    Michael_23 Member Posts: 3

    Stumped on how to wire up a hydronic zone off of a steam boiler. Any thoughts would be great. I'm a little confused on keeping the steam in check while running the hydronic.
  • Ron Schroeder
    Ron Schroeder Member Posts: 998
    the how to keep steam in check

    while running hydronic is by putting a bypass from supply to return of your zone (where they meet the boiler) with a ball valve so that you keep your temp under 180 while your making steam. Control wise Ted was right on.

  • zwickto
    zwickto Member Posts: 1
    Thermastat for Old Thayer Steam Boiler

    Our thermastat is set at 70 degrees, but today, the boiler kicked on when the temperature on the thermastat read 76 degrees. We have had 5 heating and cooling experts out to look at it and they each give a different answer. One said that the wires are not connected because the boiler does not shut off immediately if you turn the temperature down. Another took the wires and indicated that they work if tapped directly to one another, so it could be just the device that is the problem. Another turned the temperature up to 89 degrees (current temp in the house was 75) and it eventually kicked on. Who should we believe and why did the boiler kick on at 76 degrees in the house when it is set to only go on if it gets down to 70 degrees. Do these old boilers go on occasionally to keep the steam going? Can someone help explain why this might be happening?


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