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dmirza
10/06/2008, 04:01 PM
I can't get an RO/DI system to read less than 200 on my tapwater. I replaced the tank, sediment, carbon and RO membrane on my filter and it still reads 200.

I then tried outright replacing it (except fro the inlet tube feeding tapwater to the system and the outlet waste tube) and I still get a reading of 200.

I know my TDS meter is correct because I tested bottled watter. Does anybody have an idea of what could be gong on?

kgross
10/06/2008, 05:31 PM
Sounds a lot like you have something hooked up wrong. The membrane could be not seated correctly allowing water to flow around rather than through....

Kim

dmirza
10/06/2008, 05:33 PM
Yeah, that's what I though too, but I've double checked everything and I even tried a new RO unit. Still the same problem.

fishtk75
10/06/2008, 05:57 PM
<a href=showthread.php?s=&postid=13496255#post13496255 target=_blank>Originally posted</a> by dmirza
Yeah, that's what I though too, but I've double checked everything and I even tried a new RO unit. Still the same problem.

what brand and model is it? So we know to picture what you have.
And what water you have city or well water.

dmirza
10/06/2008, 05:59 PM
I don't know what brand and model I have, it's 75 gpd.

I did try this one and it didn't work:
http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&langId=-1&catalogId=10053&productId=100567554

fishtk75
10/06/2008, 06:10 PM
<a href=showthread.php?s=&postid=13496448#post13496448 target=_blank>Originally posted</a> by dmirza
I don't know what brand and model I have, it's 75 gpd.

I did try this one and it didn't work:
http://www.homedepot.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=10051&langId=-1&catalogId=10053&productId=100567554

That home depot has no DI unit and will be 200 the DI filter will take it to zero.

You need one that looks like 4 or 5 stages.

http://www.airwaterice.com/product/1TYPHOON/Typhoon_5_stage_RODI_Reefkeeper_75_GPD.html

AZDesertRat
10/06/2008, 07:18 PM
From the top:
What is your tap water TDS straight from the tap or before it goes into the unit?
Next what is the TDS coming from the blue line (if its blue, most of them are) out of the RO membrane?
What is the TDS coming out of the waste line?
If you have DI, what is the TDS after the RO/DI? Make sure to test it right out of the unit not from a pressure tank.
What is your waste ratio? It should be close to 4:1, or 4 waste to 1 good.
What is your water pressure?
What is your water temperature?

Where have you been testing from in the past? Have you made sure to triple rinse the TDS meter and container (a squeaky clean, clear glass drinking water glass with no water spots or soap residue works best to test in) in either DI water or distilled water after each test and between tests?

dmirza
10/06/2008, 11:41 PM
my tap water is at 300
Out of the RO membrane is 200
Out of the DI line is 200
My waste ration is 4:1. I just changed the component that regulates this.

I have a seperated be DI resign that color changes when it needs recharging. I recharged the cartridges and the color went back to normal, but it still is not working.

I don't know my water pressure or temperature. The temperature should be ok since the outdoor temperature has been around 80 lately

AZDesertRat
10/07/2008, 07:22 AM
What is the TDS from the waste line?

dmirza
10/10/2008, 05:31 PM
it's 340 out of the waste line.

elmosz1
10/10/2008, 08:05 PM
Your r/o membrane is not working right. You should have a rejection rate of at least 90% or a tds of 30 or less from the r/o membrane. Do you have the appropriate flow restrictor on the r/o membrane? flow restrictor link (http://www.waterfiltersonline.com/flow-restrictors.asp)

dmirza
10/13/2008, 04:37 PM
I have the appropriate flow restrictor and r/o membrand and both have been replaced very recently. I also tried replacing the whole unit, thinking that something is wrong with my setup, but I still got the same reading.

The TDS meter is working because I tested it on bottled water.

kgross
10/13/2008, 04:55 PM
It still sounds to me like the membrane is not seated correctly?

Or the new membrane is bad.

Kim

dmirza
10/17/2008, 02:49 PM
could it be that I don't have enough water pressure in my place to run the filter properly?

AZDesertRat
10/17/2008, 02:57 PM
Where did you get the RO unit from? If its a Whirlpool, Sears or some Watts Premier systems it does not use a standard 1812 series RO membrane and it will not seal correctly in the housing.
Can you post a picture of the system so we can see the plumbing arrangement and housings to help identify the source of your problems.

dmirza
10/17/2008, 03:01 PM
I bought it off ebay. I'll post a pic when I get home.

I initially thought that something was wrong with my setup too, but having also installed a GE brand filter purchased from home depot and still having the same results, I thought it might be something beyond the setup.

kgross
10/17/2008, 03:07 PM
I still think you are not seating the membrane completely. When you put the membrane in the housing, did you make sure it slid all the way into the housing so the rubber "gasket on the end is inside of the main housing? If not water can leak around the membrane and into the good water line without going through the membrane.

Or your membrane housing could be broke on the inside where the orings on the good water outlet on the membrane seat sealing the good water from the waste.

kim

dmirza
10/17/2008, 04:11 PM
I'll take another look at the membrane and it's housing. I think I installled the membrane correctly, but I'll check again. The housing being broken is another possibility. I'll take a look. Thanks for all the help.

Reefflections
10/17/2008, 05:07 PM
I thought you guys won't mnd for me coming aboard here also.I to have RODI issue also.I see where AZdesertRat asked a few questions about the unit.So took those questions and listed them below.
1.TDS from tap 140ppm/77.9 degrees
2.TDS out of the membrane 111 ppm 77.7 degress
3.TDS waste line 211 ppm 77.7 degrees
4,TDS after DI 0.7 77.7 degrees
5.pressure 98 PSI
Azdesertrat,and all the others:
Here is my total hook up.
1 Two prefilters
2.carbon
3.DI filter
4. Two resin filters
5.1 Silica filter
6.Booster pump is located before it goes into the DI unit.
Now the reason for all these add on is I'm on well water.Where the problem is the resin filters.They are supposed to go what about 6 months?Well my first one lucky will last 2 months.I just change the first resin about a week ago.And it's already turned color (brown) at the bottom of it's chamber?:mad: I can't figure out why this does this so soon.The DI is about 4 months old.And replace the sediment filters often due to the nasties the well water brings in.But I'm lost as to this ongoing issues here.I did add a booster pump going into the DI unit,because pressure was about 45 PSI.So now where do I go,and what to look for.I figure there is a reason for this.Because what I understand and have scene here.The resin should last longer,than the life I'm getting out of them.:rolleyes: But thanks for everyones help here.Just looking for some advice and HELP !:D

AZDesertRat
10/17/2008, 05:32 PM
Reeflections, are you mistakenly calling Item #3 a DI filter when in fact it is an RO membrane? I hope that is the case.

A couple of questions:
What are you using for prefilters, as in micron ranges and why two? Most domestic well systems do quite well on a single 0.2 micron pleated absolute rated prefilter, much better than on a normal spun poly filter. The pleated filter has 10x the surface area, filters to 0.2 microns absolute and lasts longer due to the additional surface area. There are also washable and/or backwashable type prefilters for domestic well systems with high silt density such as found here:
http://www.spectrapure.com/St_FILTER_ASSEMBLY.htm

What carbon block are you using?

What brand and GPD membrane do you have?

Being on a well I would also assume you have CO2 in your water which is murder on DI resins, this is probably a safe assumption.
You can research more about CO2 and its effects here:
http://www.spectrapure.com/faq_p0.htm#calcc02

You still should be getting better performance out of the membrane though. What is your waste ratio set at? Is it 4:1 or very close? Have you tried reseating the membrane in the housing? Have you looked for any evidence of hairline cracks or bad castings in the housing? This can be common in less expensive clone housings since they do not go through the ANSI/NSF approval testing process.

Do you have a pressure gauge before the booster pump to see if the pump is starving on the suction side due to plugged filters?

Reefflections
10/17/2008, 06:29 PM
<a href=showthread.php?s=&postid=13567625#post13567625 target=_blank>Originally posted</a> by AZDesertRat
Reeflections, are you mistakenly calling Item #3 a DI filter when in fact it is an RO membrane? I hope that is the case.

A couple of questions:
What are you using for prefilters, as in micron ranges and why two? Most domestic well systems do quite well on a single 0.2 micron pleated absolute rated prefilter, much better than on a normal spun poly filter. The pleated filter has 10x the surface area, filters to 0.2 microns absolute and lasts longer due to the additional surface area. There are also washable and/or backwashable type prefilters for domestic well systems with high silt density such as found here:
http://www.spectrapure.com/St_FILTER_ASSEMBLY.htm

What carbon block are you using?

What brand and GPD membrane do you have?

Being on a well I would also assume you have CO2 in your water which is murder on DI resins, this is probably a safe assumption.
You can research more about CO2 and its effects here:
http://www.spectrapure.com/faq_p0.htm#calcc02

You still should be getting better performance out of the membrane though. What is your waste ratio set at? Is it 4:1 or very close? Have you tried reseating the membrane in the housing? Have you looked for any evidence of hairline cracks or bad castings in the housing? This can be common in less expensive clone housings since they do not go through the ANSI/NSF approval testing process.

Do you have a pressure gauge before the booster pump to see if the pump is starving on the suction side due to plugged filters?
Let me try to answer some of these quastions here.The reason why 2 filters here is because of this sediment.The rope type fiber I call it,pulls the larger chunks of.I know you don't live here.But I have to deal with Georiga clay they call it.In some cases they call it pipe clay.The second filter is the one I got from Filter Guys.They set me up and the carbon and prefilters.I see you mentioned washable filters.I don't see how I could ever use these here.This red clay stains everything it comes in contact with.Without thinking about trying to wash it or even backflow the chamber.It's down right nasty clay.But on the other side we do have good water,being sitting right on top of the aquafir.As for the housing goes.It's and older model from Kent Marine/Maxima.If there was some type of crak,would we have leakage of water,which I don't have.I really can't test for flow ration,being I don't have a flow meter.Testing was donw with and HM Digital also.I see where you mention CO2/well water.Nope that's not and issue either.I've tested tap water with 2 types of testing equipment and PH IS 8.2.So can riule out CO2 issues.I've saw that about well vs.CO2 levels.So I hope I covered all the bases here.But if not let me know.And yes I did try to reset the membrane.This isn't nothing new either.It's been like this for a long time.And I keep telling myself,something isn't right.But what?

Reefflections
10/17/2008, 06:36 PM
Also forgot to give you 2 things here.Booster pump Aqutec CDP 8800
Membrane is rated at 75 gph.

AZDesertRat
10/17/2008, 06:52 PM
I would try a new membrane housing, they are pretty inexpensive. I would also try the pleated 0.2 micron prefilter in place of the two you are using now, it will filter better and last longer while probably reducing pressure loss.
How old is the membrane and what brand is it? You say you have a Kent housing but Kent does not make a 75 GPD membrane, or any membrane for that matter, they get them from someone else just like everyone does.
To calculate the waste ratio all you need is a measuring cup and a watch or clock. Time the flow from the waste line for 1 minute and note thye quantity of watre then time the flow from the good line for 1 minute and note that quantity of water. The waste should be almost exactly 4 times as much as the good flow or 4:1.

If I may make a suggestion here. There are two companies that have been in this business for about 25 years each and have much more knowledge on the subject of well and RO water than your present source. My first choice would be Charles Mitsis at Spectrapure, he has more knowledge on the subject than anyone in the industry period. The other would be Walter at Air Water & Ice in Florida. Both these guys have been doing nothing but water treatment for 25 years or more and are recognized in their field. Not to bash but FG has only been around for a few years, did not work in this field before that and do not have the experience. If you could see the laboratory and test benches in the Spectrapure facility I think you would be impressed. Thye have engineers, microbiologists and scientists on staff in their facility who do nothing but research and development or RO and RO/DI systems. Heck the reef hobbyists are only a small party of their business, they build massive systems for retail shops, LFS, coffee houses, research and medical facilities etc., no fly by nights there. If they cannot help you no one can.