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TRV's Up Feed 1 pipe steam

For one-pipe steam the TRVs attach to a special valve body--they don't replace the hand valve.

The valve body has a 1/8" male connection and replaces the existing air vent. You then add an actuator and special air vent to the valve body.


  • John Madden
    John Madden Member Posts: 19
    TRV's Up Feed 1 pipe steam

    2 Part Question!
    1] Does the TRV need to be sized as we do with a conventional radiator valve?
    2] What happens to condensate trapped in radiator when valve closes.
    I do know that if the heated area cools down before we get another call for heat there is no problem as the TRV will open and allow trapped condensate to drain back. However if that area happens to stay warm, and we build pressure before that happens???
  • Rodney Summers
    Rodney Summers Member Posts: 748

  • Kniggit
    Kniggit Member Posts: 123

    if you look back a few posts and find one about Ammark they make a one pipe TRV, sounds perfect for your aplication if you already have the radiator out.
  • bb_7
    bb_7 Member Posts: 31
    check the library


    On the library under TRVs there is a good explination of a 1 Pipe System. For a 1PS use a valve, vent, and operator to control the temp. Make sure the valve has a vacumm breaker so that the condensate can drain out of the radiator when the boiler cycles off.

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