more ro stuff

Discussion in 'Water Fed Pole Cleaning' started by Dragbag, Aug 24, 2016.

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  1. Dragbag

    Dragbag Active Member
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    ok so iv done first flush, my psi is 30 without a booster pump ( iv just ordered the one the aquatec 8800) so at 30 psi after 1 hour my tds was 35 from about about 400. my question is what was you tds before you put the booster pump on! and how long did it take for the membranes to bed in. and how much did the booster pump add to the droping of the tds txx:hehehe: what tds should i be happy with considering such a high tds start point.
     
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  2. daveyboy

    daveyboy Legend
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    What ro do you have?
    My 450gpd takes mine from 300 ish to 3-4ppm
    I have good water pressure though
    spruce would know the figures I reckon but membranes have a 90 something percent rejection rate so will never produce at 0 but i am sure when Damo had this ro as i bought it off him he got from 400 ish to under 7 with it so with decent pressure it should be quite low
     
  3. Dragbag

    Dragbag Active Member
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    i think its the same as yours collisionwater 450
     
  4. Damo

    Damo Guru
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    400ppm with decent water pressure will see less than 10ppm.

    I am guessing the RO is new?

    On the 450GPD units your looking at about 3-5 days for the membranes to bed in.

    I have changed the membranes twice on my 450GPD unit and each time the TDS after the RO doubled or even nearly trebled. Tried flushing it for a day and it make no difference.
     
  5. Dragbag

    Dragbag Active Member
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    yes m8 its new, so if it takes 3-5 days to bed in... at what tds should i run it through the 11 l di dont want to let the resin do more work than it has to
     
  6. Damo

    Damo Guru
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    As low as possible Ideally.

    I would start the RO up let it run for 5 mins. Then start putting the water through the DI.

    Unless you run the RO for 3-5 days with no DI connected I don't see as how you can get round the issue TBH :)
     
  7. spruce

    spruce Grand Master
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    #7 spruce, Aug 24, 2016
    Last edited: Aug 24, 2016
    The general consensus is that your membranes should remove between 97 and 98% plus of the dissolved solids in your water. Once that percentage drops to around 94% its time to replace your membranes.

    Unfortunately low water pressure doesn't help membrane efficiency. But good quality membranes will help. At 40psi my 450GPD did well. At 250 tap tds the pure output was 4, and that was for a few years until the pipes were relined. Our water tds dropped to 120 and the rejection rate was 2 on the same r/o.

    RoMan once told me that buying cheap Chinese manufactured membranes was false economy. They advised that the Americans were the only ones who understood reverse osmosis and it was always best to buy membranes that are made in the USA.

    The membranes I bought from them worked virtually out of the box. My experience was the same with my 4040 membrane. A 5 minute flush and the membrane was taking our 120 ppm tap water down to 2. Its done that for the last four years.

    I would imagine that Collins Water is fitting the same membranes (Vontron) as they sell which are made in China. Sorry, but my take is that as the cheapest r/o supplier I've seen, they must be reducing costs by fitting cheap components. Collins Water don't sell r/o's for window cleaning, so fitting a poor performing membrane won't be a problem in most r/o applications they carter for. They don't mention window cleaners or the like on their website anywhere I can see.

    So I believe buying a quality membrane is a good starting point to good quality pure water.

    Price wise the Chinese manufactured Vontron membranes aren't that much cheaper. An Ebay supplier has them (100 GPD) up for £20.45 each with free delivery. Collins Water has them at £23.99 as apposed to Gardiners at £23.00 + VAT (3 membranes will be no transport charge.) A membrane working at a lower efficiency is going to cost more in resin costs to polish off the pure, so cheap membranes will cost dearly over a period of time.

    The old saleman's adage comes to mind;

    The bitterness of poor quality is remembered long after the joy of a low price is forgotten.

    Obviously you are going to get better results once you fit a booster pump. However, no one can tell you what those results will be.

    -
     
  8. kevinc250

    kevinc250 Well-Known Member
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  9. Dragbag

    Dragbag Active Member
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    I think ro membranes are axion, that's what is show as in the pic on there e bay shop.
    Though I didn't notice the make when I unpacked the ro
     
  10. kevinc250

    kevinc250 Well-Known Member
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    aahhhh,collins water,a few years ago my ro packed up so i went down to collins in sheffield as i needed a solution that day came away with a brand new 450gpd unit,very nice guys at that time they were running the business from their house don't know if its still the same now.
    that 450gpd lasted around six months before the tds crept up
    it was then i bit the bullet and bought a 40/40-that was over three years ago and still on the original membrane as we speak,
    i'm still producing 4000l per week on that original membrane,
    i'm pretty certain that with care and the correct flushing methods the membrane should last around ten years or more-but thats another story.
    all too often window cleaners choose the cheapest option,your water is the cheapest peice of equipment on your van yet earns you well,whatever you want in a day.
    why buy the cheapest tat you can find because it will not last and will probably cost you much more in the long run (i found that out and in hindsight i should have gone the 40/40 route straight away as the cash i wasted would have paid for a few membranes)
     
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