Why do you need 20+ psi water pressure in a home?

Discussion in 'Homesteading Questions' started by SouthernThunder, Nov 30, 2005.

  1. SouthernThunder

    SouthernThunder Well-Known Member

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    http://www.dutchguard.com/p-oxsh-XSTREAM.html

    A link to a showerhead that runs off of 3psi and produces 1.4gpm of water. Similar models exist for sinks.

    Besides a nice shower what else requires a lot of psi in a home? Im wondering if I even need to super pressurise my water anymore... It would be a large energy savings if I didnt.

    Only thing that has me worried is the washing machine but it has a pump built into it right? What else is there?? :shrug:
     
  2. Ed K

    Ed K Well-Known Member

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    A foot of water column requires 0.434 psi. So if you have a two story house and the water comes in the bottom of the house and you're trying to push it to the top of the house or roughly 16 feet high you need 6.9 psi not counting piping losses due to friction. Add your 1.3 psi to that and you're at 8.2 psi

    would reducing pressure form 20 to 8.2 psi really save you anything?

    My dishwasher has a pressure switch that won't allow it to operate when the water is below setpoint pressure but I'm not sure the setpoint is stated in the literature
     

  3. SolarGary

    SolarGary Well-Known Member

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    Hi,
    You don't need 20 psi.
    I had a house where the water storage tank was only about 15 vertical feet above the house -- this gives 6.5 psi.

    I found that if you run large diameter (3/4 inch) supply lines to the fixtures that just about everything works fine. The only item I had trouble with was a Sears washing machine that used a timer on the fill valve -- it did not fill up the tub enough with the low pressure.

    In my case, this arrangement saved having a pressure tank and pump, and made the system more reliable.

    Gary
    www.BuildItSolar.com
     
  4. SouthernThunder

    SouthernThunder Well-Known Member

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    Hey thanks Gary, thats what I was hopping to hear. I would like to eliminate the tank and pump and associated hardware from my system and put the water tank about 20' uphill. Also like you said the system would be more reliable. I will use 3/4 lines to all my fixtures and I have been looking at the high efficiency washing machines thatr use little water anyway.
     
  5. TnAndy

    TnAndy Well-Known Member Supporter

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    Washers do have a pump on them, but the pump is to empty the washer, not to fill it.

    We have a gravity feed spring, and the pressure at the house is about 18psi. Shower upstairs is not as good as the one downstairs, but we don't use the one upstairs much anyway.

    IF you'll run 1" from the tank into the house, that will help as well.
     
  6. Alex

    Alex Well-Known Member

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    And NOT required. But, clothes washers work better with a higher pressure.

    For high-rise residential projects most developers ask us to use 30 psi as a minimum RESIDUAL pressure. Residual pressure is the pressure left-over when the water goes thru your pipes and gets to the highest and most remote fixture.

    Also, we limit the maximum pressure to 85 psi, at a fixture -- plumbing code.

    Of course fixtures can operate on much lower pressure, and that is fine, if you watch the fixture and make sure you have enough water. Before we recently added indoor plumbing at our cabin, we had two water barrels inside, behind our bed on the second floor. We had 5psi at our kitchen sink and shower.

    Ours was an excellent gravity system, functioning well on 5 psi. But, we didn't have a dishwasher or clothes washer.

    Have fun, experiment!

    Alex