can I do this with an old RO

lost in it all · 10/18/2009, 06:26 PM

First off I have really bad tds in my source water and low pressure, around 650 and 40 psi. I have two ro/di systems the one is currently in use but has its own issues and the other the membrane housing was bad so i stripped out all the filters and thought about doing this with the two systems. First add an ro booster pump. Old ro, with out membrane-put a 5 micron sediment filter in the first chamber and second two di cartridges. the currently running ro- a 1 micron sediment filter, carbon and then the 5 micron coconut block and the membrane. So the water would go into the first chamber on the old system up to the first chamber on the current system through it and then back to the two di cartridges in the old system. photobucket wouldn't let me upload so I had to attach hopefully it worked.

lost in it all · 10/18/2009, 09:49 PM

Anybody have any advise at all was looking at ordering everything I need tonight or tomorrow. I guess mainly concerned about the pressure after four pre-filters?

Got a better picture.

Buckeye Hydro · 10/19/2009, 06:23 AM

First - remember that prefilters don't remove tds. So although you have high tds in your feedwater, adding more prefilters won't address that siuation.

If you have heavy sediment loads (i.e., UN dissolved solids), running a 5 mic sed followed by a 1 mic sediment filter is fine.

Now, on the the carbon. Unless you have chloramines, you really have no need for two carbon stages. Regardless, a standard GAC stage has no place in your system - these filters are a carry over from the low capacity (e.g., 12 gpd) drinking water systems, and they don't belong in a system like yours. I believe some low-end vendors include them because they don't know any better, and/or they sell retrofitted drinking water systems that come to them assembled from overseas with the GAC filters already in them, and /or they know that many unsuspecting buyers think "more stages = better filter," and GAC filters can be very inexpensive for vendors.

Good idea to get rid of the horizontal DI carts. Those are made for use with GAC, not DI resin - but again they are used by low end auction site vendors for DI resin for many of the reasons I mentioned above.

Your pressure gauge should be teed into the line that feeds the "in" port on the RO membrane housing rather than where you have it now.

I would move the "in" probe of your tds meter to the line containing RO water that feeds the DI. Have the "out" probe on the line that comes out of the DI stage. If you are going to have more than one DI stage, we should talk further about where to place the probes, including getting an additional meter.

Russ @
Buckeye Field Supply

lost in it all · 10/19/2009, 02:29 PM

buckeyefs- Thanks for the response, If I read that right then, you are saying I don't need the middle cartidge and could just go with the three prefilters? two sediment and the cocunut carbon block.

Buckeye Hydro · 10/19/2009, 03:41 PM

Start with just two prefilters, a 1 micron sediment filter and a sub-micron carbon block. Unless you have heavy sediment loads, or a contaminant issue that requires extra carbon (like chloramines), you may not need more than those two filters.

If for instance your sediment filter clogs too quickly, you could add a 5 mic sediment filter in front of the 1 micron.

As long as you have adequate pressure (and a pressure gauge), un-needed extra prefilters won't hurt anything other than your wallet.

Russ

lost in it all · 10/20/2009, 04:15 AM

I guess I don't know what heavy would mean, it was suggested to me that when the sediment filter turns a fairly solid brown (or the entire thing is brown) it is time to change. well thats about every three weeks or so thats why I figured I should go with both a 5 micron and 1 micron filter.

Buckeye Hydro · 10/20/2009, 12:24 PM

Quote:

Originally Posted by lost in it all

I guess I don't know what heavy would mean, it was suggested to me that when the sediment filter turns a fairly solid brown (or the entire thing is brown) it is time to change. well thats about every three weeks or so thats why I figured I should go with both a 5 micron and 1 micron filter.

YES - that sure qualifies as heavy sedimetnloads.

Are you sure its not iron?

Russ

das75 · 10/20/2009, 02:34 PM

Russ, are chloramines harmful to membranes?

Buckeye Hydro · 10/20/2009, 07:13 PM

In general, no, chloramines will not harm a membrane. Its not unusual however for free chlorine to be present with the chloramine. The chlorine should be removed from the feedwater before it hits the membrane.

BTW - the membrane won't remove the chloramine.

Russ

lost in it all · 10/21/2009, 03:21 AM

No I am not sure its not iron, how would I tell?
again thanks for all your help

Buckeye Hydro · 10/21/2009, 04:59 AM

Does the sediment filter turn red? Do you have rust colored stains in your toilets/sinks?

Russ

lost in it all · 10/21/2009, 02:10 PM

no its not red its a brown color and no stains

Buckeye Hydro · 10/21/2009, 02:23 PM

probably not iron then

10/18/2009, 09:49 PM	#2
lost in it all Registered Member Join Date: Dec 2008 Location: North Dakota Posts: 95	Anybody have any advise at all was looking at ordering everything I need tonight or tomorrow. I guess mainly concerned about the pressure after four pre-filters? Got a better picture. Last edited by lost in it all; 10/18/2009 at 09:58 PM. Reason: added picture

10/19/2009, 06:23 AM	#3
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	First - remember that prefilters don't remove tds. So although you have high tds in your feedwater, adding more prefilters won't address that siuation. If you have heavy sediment loads (i.e., UN dissolved solids), running a 5 mic sed followed by a 1 mic sediment filter is fine. Now, on the the carbon. Unless you have chloramines, you really have no need for two carbon stages. Regardless, a standard GAC stage has no place in your system - these filters are a carry over from the low capacity (e.g., 12 gpd) drinking water systems, and they don't belong in a system like yours. I believe some low-end vendors include them because they don't know any better, and/or they sell retrofitted drinking water systems that come to them assembled from overseas with the GAC filters already in them, and /or they know that many unsuspecting buyers think "more stages = better filter," and GAC filters can be very inexpensive for vendors. Good idea to get rid of the horizontal DI carts. Those are made for use with GAC, not DI resin - but again they are used by low end auction site vendors for DI resin for many of the reasons I mentioned above. Your pressure gauge should be teed into the line that feeds the "in" port on the RO membrane housing rather than where you have it now. I would move the "in" probe of your tds meter to the line containing RO water that feeds the DI. Have the "out" probe on the line that comes out of the DI stage. If you are going to have more than one DI stage, we should talk further about where to place the probes, including getting an additional meter. Russ @ Buckeye Field Supply

10/19/2009, 02:29 PM	#4
lost in it all Registered Member Join Date: Dec 2008 Location: North Dakota Posts: 95	buckeyefs- Thanks for the response, If I read that right then, you are saying I don't need the middle cartidge and could just go with the three prefilters? two sediment and the cocunut carbon block.

10/19/2009, 03:41 PM	#5
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	Start with just two prefilters, a 1 micron sediment filter and a sub-micron carbon block. Unless you have heavy sediment loads, or a contaminant issue that requires extra carbon (like chloramines), you may not need more than those two filters. If for instance your sediment filter clogs too quickly, you could add a 5 mic sediment filter in front of the 1 micron. As long as you have adequate pressure (and a pressure gauge), un-needed extra prefilters won't hurt anything other than your wallet. Russ

10/20/2009, 04:15 AM	#6
lost in it all Registered Member Join Date: Dec 2008 Location: North Dakota Posts: 95	I guess I don't know what heavy would mean, it was suggested to me that when the sediment filter turns a fairly solid brown (or the entire thing is brown) it is time to change. well thats about every three weeks or so thats why I figured I should go with both a 5 micron and 1 micron filter.

10/20/2009, 02:34 PM	#8
das75 Registered Member Join Date: Oct 2002 Location: Edmonton AB Posts: 2,269	Russ, are chloramines harmful to membranes?

10/20/2009, 07:13 PM	#9
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	In general, no, chloramines will not harm a membrane. Its not unusual however for free chlorine to be present with the chloramine. The chlorine should be removed from the feedwater before it hits the membrane. BTW - the membrane won't remove the chloramine. Russ

10/21/2009, 03:21 AM	#10
lost in it all Registered Member Join Date: Dec 2008 Location: North Dakota Posts: 95	No I am not sure its not iron, how would I tell? again thanks for all your help

10/21/2009, 04:59 AM	#11
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	Does the sediment filter turn red? Do you have rust colored stains in your toilets/sinks? Russ

10/21/2009, 02:10 PM	#12
lost in it all Registered Member Join Date: Dec 2008 Location: North Dakota Posts: 95	no its not red its a brown color and no stains

10/21/2009, 02:23 PM	#13
Buckeye Hydro .Registered Member Join Date: Sep 2006 Location: Cincinnati, Ohio Posts: 4,857	probably not iron then