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Steam Radiators double trapped question

Chuck_17 Member Posts: 143
See attached.
Will this work?
1. Radiators with thermostatic traps - condensate connected to an F&T trap?
2. Two radiators condensate connected together between the above traps?


  • Jamie Hall
    Jamie Hall Member Posts: 22,972
    And why on earth would you want to do that? If the thermostatic traps are functioning as they should, there will never be anything except air and condensate in the return. If they aren't, adding an F&T somewhere isn't going to help anything. Further, most F&T traps are really lousy vents, and you want the return to have the maximum venting possible.

    In short, poor idea. Don't do it.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Chuck_17
    Chuck_17 Member Posts: 143
    To clarify, this is an existing recently installed. Radiators, TCV, T trap all new connected to an existing F&T trap.
    The questions is - should the F&T trap be removed?
    EBEBRATT-Ed Member Posts: 15,353
    Yes if all that is feeding the F & T is the two rads remove the f & T. If there are other pipes feeding the inlet of the f& T that are not trapped the connect the outlet of the thermostatic traps downstream of the f&t. That is assuming the condensate return is above the boiler water line and is a dry return. If it's a wet return you need vents to get rid of the air.
  • pedmec
    pedmec Member Posts: 943
    You would connect the drain from the thermostatic traps after the f&t on the condensate return, downstream of the f&t.
  • Chuck_17
    Chuck_17 Member Posts: 143
    Thanks for the replies.
    There is nothing else on the F&T.
    Do you think it would work with the F&T left in place?
    It is operating now but it has not been that cold.