picking submersable pump/ calculating resistance from a long run of water pipe

Discussion in 'Pumps and Tanks Well Forum & Blog' started by kavik, Dec 31, 2011.

  1. kavik

    kavik New Member

    Messages:
    1
    Location:
    tn
    I have a cistern fed by a spring and there is a submersable 4" 220 v pump in it. It is located a long way from my house. The water is pumped a little over a 1/4 mile through 1 1/4 " galvanized pipe. There is probably only 60 foot elevation rise. The pump needs to be replaced and I am wondering how to calculate the resistance of the water through the pipe in with sizing the pump. I have a barn halfway to the house with water. Currently, at 60 psi showing onthe pressure guage, water will flow at the barn, but not at the house. At 90 psi it flows well at the house also. I don't know what size/stage pump is in the cistern right now.

    As an aside, I was considering a constant pressure type pump, as the water volume at the house does vary cosiderably as the pressure tank drains/system cycles- anyone have any experience with them?

    thanks
    Last edited: Dec 31, 2011
  2. Tom Sawyer

    Tom Sawyer In the Trades

    Messages:
    3,184
    Location:
    Maine
    You can find charts online or from pump companies that will give you the resistance
  3. masterpumpman

    masterpumpman New Member

    Messages:
    729
    Location:
    Virginia Beach, VA
    My advise is to stay away from the variable flow pumps as they are a technological nightmare. Installing a Cycle Stop Valve in the line between the pump and tank is much less expesive, all mechanical (no additional electronics), it will extend the life of your pump, pressure switch and tank and it will give you constant pressure. I think that you can find out more about it by visiting http://www.cyclestopvalves.com
  4. LLigetfa

    LLigetfa DIYer, not in the trades

    Messages:
    4,003
    Location:
    NW Ontario, Canada
    The math does not add up. You lose .43 PSI for every foot of elevation, so if there really is 60 feet of elevation from the barn to the house, there should be 26 PSI loss. 60 PSI at the barn then would be 34 PSI at the house and water should flow. How much flow of course, depends on resistance. I think you need a new pressure guage.

    As for variable speed pumps, such a long wire run would wreak havoc on the electronics.
  5. ballvalve

    ballvalve General Engineering Contractor

    Messages:
    3,261
    Location:
    northfork, california
Similar Threads: picking submersable
Forum Title Date
Pumps and Tanks Well Forum & Blog Jet pump pressure switch double picking Aug 12, 2014
Pumps and Tanks Well Forum & Blog picking a bladder tank Oct 25, 2009
Pumps and Tanks Well Forum & Blog Water rusty and full of sediment after new submersable well pump was installed May 17, 2013
Pumps and Tanks Well Forum & Blog Jet pump to submersable conversion questions. Sep 8, 2012
Pumps and Tanks Well Forum & Blog replacing check valve on submersable pump??? May 6, 2011

Share This Page