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steam main size

Gentlemen, recently while conducting a steam class for the local union, we mentioned that the empire state building uses low pressure vacuum steam to heat the building ; one of the students asked..." what size are the mains?" i didn't know the answer but said i would find out? does anyone out there know? it is a good question.

thanks, t.p. tunstall


  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,523
    Very good question

    I know the building runs on ConEd steam and that it's a vacuum system. The pressure is typically 1-1/2 psi, with a high of 3 psi on the coldest day.

    The building was prefabbed and assembled more than built, with the materials needed on any given day arriving on that day. It took just 18 months from the time they knocked down the old Waldorf Astoria hotel until the first tenant moved in.

    I'll see if I can learn more about the pipe sizes. Thanks, T.P.
    Retired and loving it.