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nickmg555 Member Posts: 16
edited November 2019 in Plumbing


  • Ironman
    Ironman Member Posts: 6,589
    edited May 2019
    Pipe sizes are determined by the btus required.

    Generally speaking, here's a chart:

    Stay in the middle, between minimum and maximum. Which means:

    1/2" = 2 gpm
    3/4" = 4 gpm
    1" = 8 gpm

    You need to FIRST do a scientific heat loss calculation to determine what size equipment, radiators, piping and pumps are needed.

    SlantFin has a free app that you can download. Disregard any quick, square footage calculators that you may find. They're worthless.
    Bob Boan
    You can choose to do what you want, but you cannot choose the consequences.