Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.
If our community has helped you, please consider making a contribution to support this website. Thanks!

Head Pressure in Primary loop

Options
DanHolohan
DanHolohan Member, Moderator, Administrator Posts: 16,687
in THE MAIN WALL
Retired and loving it.

Comments

  • Rob_34
    Rob_34 Member Posts: 21
    Head Pressure in Primary loop

    How do you figure the head pressure in a hydronic loop? Primary loop, 2" needing to produce 300K Btu. Approximately 25 feet. Is that enough information?

    Rob
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,687
    You should

    get a copy of this book Primary-Secondary Pumping Made Easy!.

    It's an easy read and it will get you away from sizing on that 20-degree temperature drop that's costing you money on every job.
    Retired and loving it.
  • Andy_14
    Andy_14 Member Posts: 121


    Hey Dan,

    I ordered Pumping Away last week. Will that also answer these questions? Thanks
  • Rob_34
    Rob_34 Member Posts: 21


    Okay Dan, I was reading that and thinking about dropping it to a 30 degree delta T and would be able to use 1 1/2" instead. Okay then how do I figure the head pressure to push the +-20 gpm around that 25 foot primary loop?
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,687
    copper?

    Retired and loving it.
  • Rob_34
    Rob_34 Member Posts: 21


    Yes, Copper. Will be feeding it with 2 Trinity boilers, a 150 and a 200. I heard you sell a little black book that helps determine these things.

    Rob
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,687
    At 20 gpm

    the pressure drop will be 4' of head per 100' of pipe. That doesn't include the allowance for fittings, though. I'm doing this with a B&G System Syzer. Do you have one of those?
    Retired and loving it.
  • Andy_14
    Andy_14 Member Posts: 121


    I guess maybe I should have ordered that book then. From the description it seems as though the Primary Secondary book will have most all the pumping away stuff in it.

    Or is pumping away not covered in the primary secondary book?
  • Rob_34
    Rob_34 Member Posts: 21


    No I don't. Do you just go on their website to get it?

    Thanks,


    Rob
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,687
    From their local rep,

    or you can go HERE and download the electronic version.
    Retired and loving it.
  • DanHolohan
    DanHolohan Member, Moderator, Administrator Posts: 16,687
    It's in there,

    but one book really does follow the other, with Pumping Away first.
    Retired and loving it.
  • Rob_34
    Rob_34 Member Posts: 21


    Thanks,

    Rob
This discussion has been closed.

Categories