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Fixture Calculator, you need to use this!

hot_rod Member Posts: 22,144
If you do plumbing work and size equipment and piping, download the free updated calculator is a much needed revision to the 80 year old Hunters Tables and greatly reduces piping size, PRV, mix valves, etc.

Almost on a daily basis we get calls about misbehaving TMV. Most often the valve is over sized or grossly overside and cannot regulate properly.

Don't size any control valve by the pipe it will connect to :) Use tables and manufacturers charts and Cv numbers.


Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream
ZmanratioTinmanBigRobErin Holohan Haskell


  • RayWohlfarth
    RayWohlfarth Member Posts: 1,483
    hot rod Thanks that's awesome
    Ray Wohlfarth
    Boiler Lessons
  • Jamie Hall
    Jamie Hall Member Posts: 23,302
    Wish I'd had that back in the day!
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England