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Water saving.

  1. Jun 18, 2012 #1
    I would like to consider a little provlvthat have occured in my own house. I live in very old house whose water tubes transport water really long time. Also there is a gas furnance which heats the water reaaaaly lobg time. To take a shower I need to turn on a tap and wait for hpt water.

    The main topic of this thread is.. How to save the wter which is spend to get hot water. I ll describe ot here and maybe draw some plan of the house to present ways to use it. To get hot water I lose 6-8 l. Before I draw do you know any mechanisms to redirect water? Best way would be in my opinion to use it to water the garden which is just next to the toilet. I ve considered option to jus place a rubber hose ... But its quite ..inelegant. Thats just a beginning if you have any ideas ill send a house plan here. :)
  2. jcsd
  3. Jun 18, 2012 #2


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    Instead of trying to find a way to use the wasted water while you wait for it to heat up, have you considered installiing an On-Demand Water Heater system?



    It may even be more energy efficient (lower electric/gas bills) in the long run...
  4. Jun 18, 2012 #3
    That's probably the best option. You could re-route the water with some valve to a different destination manually, for instance install a tank that stores water that is used to flush the toilet, but these things are pretty tedious.
  5. Jun 19, 2012 #4
    Indded but It will not work. There is no place to mount it. I search for way to use this water in the time when its flowing. Of course this is great Idea this on-demand heater. But it would not work in my house. The water tubes are really old. Believe me their construction is like before Great War. :) Best solving for this ptoblem is to retrack it.. To the garden... Or Maybe transform it to the energy which is much harder to do.
  6. Jun 19, 2012 #5
    How about this then:

    Install a valve with a thermostat, which will redirect the water to wherever you want it to until it starts having the proper temperature. You would need a pretty descent valve and maybe a timer or some common sense so that if for some reason the water never reaches the desired temperature, you won't flood your garden.
  7. Jun 19, 2012 #6
    6 to 8 liters? I don't see you saving too much money by saving 6-8 liters of water per shower... That's like shaving off a minute of shower time per session.

    Apart from rerouting your hot water lines, I don't see any sensible, low-cost solution (or reason).
  8. Jun 19, 2012 #7
    [3 person x 7l ]x 30 days = 810 l per month. And have you aver heard about water-diamond paradox? Water is the.mlst precious thing on the world. I dont care about money im gona save.. I care about water :) :) :)

    Meldraft thats pretty nice idea. Ill make a picture of it and post it here. Tomorrow. You will tell me is that wat you thought about. :) If you would like to ofc .
  9. Jun 26, 2012 #8
    Sponge baths instead of showers (or regular baths) save loads of water.
  10. Jun 27, 2012 #9


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    Staff: Mentor

    Save water: shower with a friend.
  11. Jun 27, 2012 #10
    ^^ This :biggrin:
  12. Jun 29, 2012 #11
    Haahahaaha . Ok we have the winner.
  13. Jun 30, 2012 #12


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    Staff: Mentor


    There are two interesting water-saving inventions I've seen demonstrated for the shower. They are not practical for your DIY situation, but have potential for new constructions.

    The first addressed your problem, of the initial flow being wasted. I believe they redirected this back to the inlet of the HW tank. A pump would be needed, and a few valves, but all can automated.

    The other invention involved a valve in the shower's drain and allowed a user to recirculate the water and enjoy an endless hot shower without wasting more. The valve was foot-operated, and behind the wall was a pump and water heater, and a filter incorporating a UV sterilizer. The idea being that the initial soapy water would be let flow away, but after that if the user desired, the water could be endlessly recirculated. Not merely luxury, but those who find long hot showers therapeutic would appreciate the benefits of such an installation.
  14. Jun 30, 2012 #13
    The second one is really really interesting. But many people will reject that idea. Unfortunately :) . It reminds me stillsuit from Dune :D endlessly recirculated :)
  15. Jun 30, 2012 #14


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  16. Jul 1, 2012 #15


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    It sounds like the water pipes have a significant amount of scale (metal oxide layer, corrosion products) built up over time. The scale increases pipe roughness, decreases the effective inner (hydraulic) diameter and increases thermal (heat transfer) resistance. It's perhaps time to start replacing the water pipes. Otherwise an on demand water heater located as close as possible to the point of use as berkeman indicated would seem to be the best solution.
  17. Jul 1, 2012 #16


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    Gold Member

    In Latin America, it is common to have an electric water heater integrated into the shower head.
    While some may freak out at the idea, it works very well and if properly installed with a GFI is perfectly safe.
    That way, your aging plumbing can rest in peace and you get the hot showers at a predictable cost.
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