[geefree]

Hi i am confused. i am looking to get wfp and have emailed steve at freshwater (very helpful)

but i have looked at some ro- units  and steve said them alone are not enough to completely purify the water as i live in a hard water area ( i told him that)...

so i would also need di and resin etc...

now on ebay i found a ro-unit which also had a di-unit attached..... is this ok ? i will post it if need be  so you guys can see ....

but now i have just seen the di- alone for hundreds of pounds...
whereas the one above was around £150...

now i will confuse you    can someone please explain the lingo below..... this is a question from a potential buyer of a ro unit on ebay.....

quote " do all the filters need renewing? or is it just the sediment and carbon ones? thanks rob.
 04-Oct-06 
 A: hi ,i tested output for nitates and tds all where zero. i have left the filter full of water so membrane is fine too. hth Regards Richard. " unquote
 
 Ask seller a question
 
please can anyone explain that is double dutch to me.

thanks very much.

gary.

[Extremeclean]

An RO unit on its own wont get rid of 100% of the solids in the water. It will get rid of 90% plus but there will still be some solids left in the water. This is why the DI unit is needed. Just to polish off the last few % of solids.

Like all machines ther are many types and sizes so you could pay say thousands for an RO but it would be far to much for your needs. The principle is the same though no matter what size or price of RO/DI units.

Most RO units have a series of prefilters which need to be replaced say every few months but thet are really quite cheap. £20 to 30 for a set. 

Now to try and keep it simple but probably confuse you even more DI resin on its own is capable of purifying the water without an RO unit BUT it does have a finite life so if you are in a hard water area passing your water through an RO first will save you a lot of money because you wont use much DI resin at all. EG if your RO takes out 95% of the solids your DI resin will last around 20 times as long.

I budget for 1 x 25 ltr bag of resin per man on domestic work per year at around £80 to 90 per bag.  Without RO it would be 20 times that so the cost would be more like £1600 to £1800   just for resin. 

The sequence is tap....RO.. then DI.  The one on Ebay has a very small DI resin vessel. It will produce pure water but you will have to replace resin more often than with one that has a bigger DI vessel.

Its all VERY simple really but not so easy to describe in words. Steve is telling you the truth so trust his word and advice.  BTW I have never spoken to or dealt with him in any way but he is telling you the way it is.

Oh and DONT buy a 2nd hand RO unit. New ones are cheap enough and you know what you are getting.

[geefree]

Cheers Extreme,

As always really good advice, where would i be without yer

it all sounded so confusing but you wrapped it up for me and i totally understand now,

as i go along i suppose i will learn more regarding filters etc... oh what about a td something metre ? etc  i have heard i need that at some stage...


If i get things wrong , will i leave the windows dirty?

even 98% of pure water say?

but thanks a lot anyway i git it now, so do you think i need a standard ro unit... and a seperate decent di?

sorry to all for the boring questions after your hard day.... but i am afraid i am here to stay

thanks extreme.

gary.

[Extremeclean]

OMG you are here to stay!!!   

No its fine Gary. 

OK yes you do need a TDS meter.  To explain TDS.  It stands for TOTAL DISSOLVED SOLIDS and measures these in PARTS PER MILLION.  So a reading of say 350 would mean that you have 350 parts per million of solids in your water.  The objective of using RO/DI is to get this down to a reading of zero which means that your water is totally free from suspended solids.

NO a reading which would equate to 98% removal wont do.  UNLESS you lived in a soft water area say where your TDS reading in is 50 so that you would have a reading of 1 coming out.  That would work fine but if your TDS in from the tap was say 400 you would at 98% be getting 8 out which is a bit too high really.  PHEW I hope this is making sense.

Look its easy enough.  The pure water is a tool so you should use a good one which would mean using water with a reading of zero.  I allow mine to get up to 4 MAX. Others may differ slightly but in  reality it should be zero. Thats easy enough to achieve and maintain.  Use a hand held TDS meter. They are much more accurate than most inline ones and at £13.99 cheaper as well. There is one on Ebay now for £13.99. It looks like a HM digital one and these are generally very good.

[Pj]

As well as asking on here, google r/o and swat up on info for filtering water for windowcleaning, wherever you can find links.
This is not directed at anyone so don't get me wrong, but be reminded that all suppliers will be very nice and helpful if they know you are in the market to part with some 'reddies', nothing wrong with that, but just remember....Buy what you want, don't be sold what you don't need.
you will need a filtering system with pre-filters, an r/o membrane and a di cylinder(resin).
Google RO-man  

[geefree]

thanks extreme,

 will watch what i am doing now and try to buy the right things...

and cheers p.j.

it does pay to shop around .

gary.

[geefree]

can you guys have a look at this please and tell me if ok to buy,, will it do the job.?

http://cgi.ebay.co.uk/Reverse-osmosis-100-GPD-6-Stage-RO-SYSTEM-WITH-DI-UNIT_W0QQitemZ200034577235QQihZ010QQcategoryZ20756QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

[Pj]

it's this one, first on the page, £130 new from RO-MAN
http://www.ro-man.com/shop/index.php/cPath/22


100 GPD means: 100 gallons produced in 24 hours when working at peak performance.
You have to decide if that will meet your demands.  100gals is about 400litres I think.
Most use between 1 1/2 - 2 1/2 litres per minute, when cleaning.  So you could use roughly 400litres a day when working an average day.
Think bigger!  Maybe 200GPD is a better buy in the long run.

[john tomkins]

Gazza this is the one I got http://www.ro-man.com/shop/product_info.php/cPath/22/products_id/122?osCsid=d8b915d8f09b66355b00c734d18ec7b5

A bit more expensive at £145 but has got the inline TDS and pressure gauge, I get 12 ltr per hour on a 65psi water pressure, plenty for me at present and can always double output by adding another membrane for £50 ish.

[freshwater]

Gary,

All good answers.

ROs with fitted DI units tend to have small capacities  about 0.7 of a litre of resin (they will only remove a small quantity of TDS) the vessel types hold 12 litres or so, hend the price difference. Depending on what your TDS is after the RO (about 5 th 10% of the input) sould decide wch is best for you. If you tds is on the high side say 20ppm plus then go for vessel cos you will be refilling the small cartrige type all the time.

Our 4 stage RO can be configured with the last housing as a de-min is on the RO page you looked at before. http://www.freshwatersystems.co.uk/aquatic_ro_systems.htm
and costs £85 inc vat and delivery.

Gaz dont buy the 6 stage ebay RO its expensive and has filters you dont need.

With regard to PJs reply if it says 100GPD you will be doing well to get 50GPD out of it. This is because ROs are tested with water at 25 'C, but your tap water will be about 5 'C, and cooler water reduces the capacity of the membrane.

[geefree]

thanks once again for all help..
steve can you give me a link for the di vessel please... also have just looked at the link above, think i will go for the 200gpd, but does that also have a di thing attached . cheers

gary

[freshwater]

Gazz,

If you want the DI in the third housing the pic is the same, three housings with the memnbrane on top, if you want the large vessel then they are same as the veesels we use on our whole house filters http://www.freshwatersystems.co.uk/vwhousefilters.htm
it looks like the one at the back but is the size of the one on the left.

steve@freshwatersystems.co.uk

[dougster]

gary, why dont you phone roman and speak to them, as i did and got a charming lady who explained everything i needed to know.Notice that if you purchasr the 100gpd unit for £130.00 ish, then you have postale charge of twenty, so add on the di cartridge, and you pay £157.50, so you get the di for £7.50 or something along those lines,because if you spend over £150.00 you get the free postage, and we all like to take advantage of freebies here and there dougster

[Extremeclean]

gary, why dont you phone roman and speak to them, as i did and got a charming lady who explained everything i needed to know.Notice that if you purchasr the 100gpd unit for £130.00 ish, then you have postale charge of twenty, so add on the di cartridge, and you pay £157.50, so you get the di for £7.50 or something along those lines,because if you spend over £150.00 you get the free postage, and we all like to take advantage of freebies here and there dougster

Hmmm seems a "charming lady" works very well in sales   

[MNWC]

With regard to PJs reply if it says 100GPD you will be doing well to get 50GPD out of it. This is because ROs are tested with water at 25 'C, but your tap water will be about 5 'C, and cooler water reduces the capacity of the membrane.

So if i had somehow i could heat the input water to 25.c would that increas my output ??

Marcus

[dougster]

say she is worth a payrise at least

[freshwater]

I have already offered gaz a conversation over the phone, but he hasnt taken up the offer.

As far as 25'C is concerned, yes if you gan get a temp rise you will get more out of the end.

steve@freshwatersystems.co.uk

[geefree]

THANKS AGAIN..
Steve i will call you tomorrow,

as you said its hard to explain this way,... i really did think i could get away with a di built into the ro-system,

and thanks dougster i will also speak to the lady you mentioned (did you get my email dougster?)

all good info from all of you cheers....

perhaps someone may live in this part of the worlld could post the units they use??

in fact i would be interested to see lots of peoples ro/di units and prices, certainly know then wouldnt i