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Water flow

  1. Dec 14, 2015 #1
    WATER FLOW.jpg Hi

    In this system of water flow, water enters pipe A at x pressure with the aim of pumping it to the house
    Excess water or rather recycled water is flowing back via pipe B into pipe A
    Is that possible according to the law of physics i.e. will the pressurised water attempt to flow up into pipe B and render the system invalid
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  3. Dec 15, 2015 #2


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    Indeed the pressurized water will enter into pipe B.
  4. Dec 15, 2015 #3
    what can i do to make sure water doesnt flow from pipe A into pipe B but pipe b water must flow into pipe A
  5. Dec 15, 2015 #4


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  6. Dec 15, 2015 #5


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    It should be noted that, on its own, this will still not allow what you have in B to flow into A if the pressure in A is higher. In order to accomplish this you will need a pump of some sort.
  7. Dec 15, 2015 #6
    Now, let's see if we understand this correctly. Suppose you put a hypothetical black box around the piping and the house. You have water flowing into the black box, but no water leaving. Does that pretty much describe what your diagram says? What do you think is going to happen?

  8. Dec 15, 2015 #7


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    I'm pretty sure water is leaving the black box - the return is "excess".

    I'd like to know why though. This may or may not be code compliant or effective.
  9. Dec 16, 2015 #8
    A jet pump is used in kind of the way drawn, but AFAIK it is the recirculating water from B drawing in water from the A source.
  10. Dec 18, 2015 #9


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    Why is there even any need for branch B? If we assume the house draws only what it needs from path A then any so called "excess" will just stay in pipe A.

    If the house draws too much then the "excess" will have to be re-pressurised in order to inject it back into A or any other pipe at the same pressure.

    If you build it as illustrated, water won't go around the loop without a pump.

    I think it might help if you explained what you are trying to achieve.
  11. Dec 30, 2015 #10
    If you are trying to put recycled water back into a pressurized water system, you will need a pump to force it into the water main. If the water main has a check valve upstream where the home line is connected to it, (I imagine it will) you will only be able to force the water into the main line when it is displaced by consuming it in the house. There is the potential of bursting the line if the pump pressure isn't limited somehow because what goes in must come out somewhere. See attached.

    This is all theoretical, I don't know the ins and outs of household plumbing.

    Attached Files:

  12. Dec 30, 2015 #11
    By design, I'm sure there is a one-way check valve where the house connects to the water main that feeds it. If there weren't, potentially, anyone could contaminate the water supply by simply pumping a contaminate from their house into the water system.
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