rodi hookup problem

Discussion in 'Filters, Pumps, etc..' started by armison89, Jun 11, 2011.

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  1. armison89

    armison89 Purple Spiny Lobster

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    any other way i can increase the psi? the booster pump costs to much
     
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  3. AZDesertRat

    AZDesertRat Giant Squid

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    Check your home to see if you have a pressure regulator on the incoming water supply. Many new homes have them per building code and they are often set too low, most are adjustable.
    If you don't, unfortunately it is what it is and there is no changing it. You might watch the pressure at different times during the day, sometimes off peak times like late at night or mid morning have higher pressures due to lower demands.

    Make sure you checked the waste ratio closely, too much waste lowers pressure to the membrane dramatically since the water is taking the path of least resistance. If your tap TDS is pretty low you can get by with 3:1 waste to treated but not any lower. This may help raise pressures a little.
     
  4. armison89

    armison89 Purple Spiny Lobster

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    im using well water so i think my watse is really high
     
  5. AZDesertRat

    AZDesertRat Giant Squid

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    Measure your waste for one minute with a measuring cup then do the same with the treated water to determine your waste ratio. It should be about 4 times as much waste as good, higher or lower is not desirable.
     
  6. jeff@zina.com

    [email protected] Flamingo Tongue

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    The waste ratio isn't a product of the type of water, it's the efficiency of the membrane affected by things like pressure, temperature, etc. In general, 3-1 or 4-1 are standard waste ratios, most rut at or near 4-1, four parts waste for each part good water.

    Jeff
     
  7. AZDesertRat

    AZDesertRat Giant Squid

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    The waste ratio has noting to do with the efficiency of the membrane, they are two entirely different things. One is rejection rate or membrane efficiency and the other is waste ratio or how much water yoy use to keep the membrane flushed of solids when it is in use.

    4:1 is the industry standard for waste ratios, 4 parts waste to 1 part treated so you keep the membranes surface free of debris.

    Water temperature and water pressure will have some effect on the waste ratio but not nearly as much effect as it has on the rejection rate or membrane efficiency.
     
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  9. jeff@zina.com

    [email protected] Flamingo Tongue

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    You learn something new every day. I was under the impression this was one and the same thing, basically water passed versus rejected. Thanks for the clarification.

    Of course, now it makes some of the spec literature more confusing... :)

    Jeff
     
  10. armison89

    armison89 Purple Spiny Lobster

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    my waste ratio is 7:1
     
  11. gt40425hp

    gt40425hp Feather Duster

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    waist of 7:1 is exesive and is possibly leading to the low pressure order a new restrictor match it to your gpd of your unit here is a link
    RO MEMBRANES AND FLOW RESTRICTORS
     
  12. AZDesertRat

    AZDesertRat Giant Squid

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    If you adjust that back to 4:1 you will have more pressure available to the membrane which means more GPD and better rejection rate or removal efficiency. Not to mention the obvious waste water savings.