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Is there an online calculator taking btus load, pipe size and length...

Is there such a thing as an online calculator where you can plug in your btus load, pipe size and length, and have it give you pump recommendations or at least head and flow?


  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 8,166
    edited February 2023
    Are you looking for a commercial application? OR are you looking at residential system (less than 300,000 BTUh)? For the small stuff, a simple rule of thumb is found here: https://documentlibrary.xylemappliedwater.com/wp-content/blogs.dir/22/files/2020/01/FH-Z100B-BG-Zoning-Made-Easy-2.pdf starting on Page 5 and ending with this

    But I may have used a slide rule in the past. Now there's an app for that.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

    EBEBRATT-Ed Member Posts: 15,833

    The best way is to use the old Bell and Gossett wheel that Gill Carlson invented. You can get one from your local B & G rep. If you want the electronic version, you can use the B & G "system sizer" which you can download for free from B & G (zylem) web site.

    Like any calculator the more accurate the #s you put in the more accurate your answer will be.

    Once you have the pump head and flow calculated you can call your pump supplier and they will size the pump.
  • hot_rod
    hot_rod Member Posts: 22,472
    Turn your btu loads into gpm required as @EBEBRATT-Ed suggested.
    Then find pipe sizing tables online. The Plastic Pipe Institute has a great one for any plastic pipe material.
    Copper or steel pipe at engineeringtoolbox.com
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream