Advice on this RO/DI build

swull · 05/28/2011, 07:07 PM

Rebuilding My RO/DI system and would like to see if there are any problems with this build before i order parts. I left valves and connections out of Illustration. Using parts from 2 previous systems and ordering the rest.

sjm817 · 05/28/2011, 07:29 PM

5 stage prefilter seems a bit excessive. Do you have a reason for this? I would go with a dual DI. I see you didn't diagram in valves, but you have the checkvalve to keep the pressure tank water from going through the DI?

dlp211 · 05/28/2011, 07:36 PM

I'd move your 5 micron sediment filter to before the booster pump.

iamwrasseman · 05/28/2011, 07:53 PM

it may work but it seems a bit over kill to me .

swull · 05/28/2011, 08:26 PM

yeah its a bit over kill, but i have 5 prefilter canisters already, so i thought i would throw some filters in them. My tap water is treated with chloramine so i figured threee stages of carbon would help with that. The 2 sediment fiters could be reduced to 1, considring i have a whole house sediment filter. Should i just remove one sediment filter and go 4 stage prefilter?

There is a check valve before the supply side of di canister and a on/off valve on the out side of canister. From what i read (could be wrong), u put a check valve before the di canister to prevent DI water from running back to faucet and storage tank, but allowing the RO storage water to run through when i open valve to get DI water.

But if You have a on/off valve (in Off position) after DI canister that should prevent back flow right?

Thnx for the advice

sjm817 · 05/28/2011, 08:39 PM

You dont want the storage tank water to go through the DI. I would use one of those extra canisters as a 2nd DI.

Here is check valve placement:

swull · 05/28/2011, 10:02 PM

My ro(drinking water) goes straight to faucet not through di filter. There is a tee in the ro line that goes to the di filter. Not sure why using fresh ro water straight from membrane is different than using stored ro water to make di water?

2nd di filter sounds good.

sjm817 · 05/28/2011, 10:09 PM

The drinking water should not and does not go through DI in the diagram above. That 6th stage is a carbon drinking water post filter.

The fast high pressure flow from the storage tank is not good for DI life.

Dual DI with color change is nice. Once DI #2 starts to change color, move it to DI #1 and put in a new DI #2. This way you are always getting the max life out of your DI and never have an expired DI.

swull · 05/28/2011, 10:22 PM

I was describing my tank, your diagram is good. Sorry for not making my post clear. I was just confused on the storage tank water. I did'nt know that the higher flow was bad for di. Thnx for the Info Scott.

05/28/2011, 07:53 PM	#4
iamwrasseman Registered Member Join Date: Oct 2008 Location: syracuse Posts: 7,003	it may work but it seems a bit over kill to me . __________________ This hobby certainly can put you in some weird positions ! Dave Current Tank Info: 40 freshwater,25saltwater 2000 gallons ,enough tanks for an army ?

05/28/2011, 08:39 PM	#6
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	You dont want the storage tank water to go through the DI. I would use one of those extra canisters as a 2nd DI. Here is check valve placement: __________________ - Scott

05/28/2011, 10:09 PM	#8
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	The drinking water should not and does not go through DI in the diagram above. That 6th stage is a carbon drinking water post filter. The fast high pressure flow from the storage tank is not good for DI life. Dual DI with color change is nice. Once DI #2 starts to change color, move it to DI #1 and put in a new DI #2. This way you are always getting the max life out of your DI and never have an expired DI. __________________ - Scott

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
BRS RO/DI vs The Filter Guys vs Filter Direct????	Bigjav	Lighting, Filtration & Other Equipment	56	01/21/2012 11:04 AM
(another) RO/DI question	blue ridge reef	Lighting, Filtration & Other Equipment	7	01/18/2012 09:26 PM
ro/di questions/problems	Arthur1	Lighting, Filtration & Other Equipment	8	10/08/2009 05:27 PM
RO/DI unit	blcketnies11	New to the Hobby	7	11/02/2008 01:46 AM

05/28/2011, 07:29 PM	#2
sjm817 On Yer left! Join Date: Sep 2004 Location: Northern VA Posts: 18,777	5 stage prefilter seems a bit excessive. Do you have a reason for this? I would go with a dual DI. I see you didn't diagram in valves, but you have the checkvalve to keep the pressure tank water from going through the DI? __________________ - Scott

05/28/2011, 07:36 PM	#3
dlp211 Registered Member Join Date: Apr 2011 Posts: 591	I'd move your 5 micron sediment filter to before the booster pump.

05/28/2011, 08:26 PM	#5
swull Registered Member Join Date: Jan 2004 Location: Murrieta, CA Posts: 80	yeah its a bit over kill, but i have 5 prefilter canisters already, so i thought i would throw some filters in them. My tap water is treated with chloramine so i figured threee stages of carbon would help with that. The 2 sediment fiters could be reduced to 1, considring i have a whole house sediment filter. Should i just remove one sediment filter and go 4 stage prefilter? There is a check valve before the supply side of di canister and a on/off valve on the out side of canister. From what i read (could be wrong), u put a check valve before the di canister to prevent DI water from running back to faucet and storage tank, but allowing the RO storage water to run through when i open valve to get DI water. But if You have a on/off valve (in Off position) after DI canister that should prevent back flow right? Thnx for the advice

05/28/2011, 10:02 PM	#7
swull Registered Member Join Date: Jan 2004 Location: Murrieta, CA Posts: 80	My ro(drinking water) goes straight to faucet not through di filter. There is a tee in the ro line that goes to the di filter. Not sure why using fresh ro water straight from membrane is different than using stored ro water to make di water? 2nd di filter sounds good.

05/28/2011, 10:22 PM	#9
swull Registered Member Join Date: Jan 2004 Location: Murrieta, CA Posts: 80	I was describing my tank, your diagram is good. Sorry for not making my post clear. I was just confused on the storage tank water. I did'nt know that the higher flow was bad for di. Thnx for the Info Scott.