RO/DI installation question

swenard

New member
I just got my new RO/DI unit and it looks great. I just have a question about installing it. I would like to install it in the basement for my aquarium needs but also want it to run to a tap at my kitchen sink. Does it matter how far it is mounted from the sink to work properly?

I had a culligan guy in awhile ago giving me a quote on a water softener and Ro unit; at that time he said he would have to install the RO unit directly under the sink or it would not have enough pressure. Is that true? I could easily install it under my sink, but it is a bit cramped for space.
 
Do you have a storage tank for your setup? With out one the water will be painfully slow. You could put the whole system in the basement and run a line up to the RO faucet in the kitchen. It would work fine.

My system is opposite now, but soon to change. My system is under the kitchen sink and then a 25 foot line runs down to the basement for the sump. I am going to change it around soon. I want the space back under my sink.
 
a 25 foot run shouldn't be too bad (my tap is about 15 feet from my RO unit-- my RO unit is in my basement)-- if real long it might affect the flow somewhat... you could adapt up to and use 3/8 tubing instead and then back down to 1/4" at the spigot-- this would reduce flow type friction-- I would run 1/4" tubing and see how it does before trying to fix it... if your house water pressure is real low, then it might run kind of slow-- my pressure is about 45 psi (well water) and I don't think my flow is too bad. If you have city water then your pressure will be higher so your flow will likely be less affected.

As mentioned above, you will need a pressure/storage tank for water on demand... mine is about 1 1/4 gallons... I'd go bigger if you could... not quite enough at times for cooking (making spaghetti and stuff)
 
I do have a tank and it is 4 gallons. So I could mount the tank and the sytem in the basement and run the one tube up to the sink then?
It would be nice if I don't have to mount the big tank under the sink.
 
You shouldn't have a problem as long as you have a tank. They're presurized to push water out. However, if you DO find the flow is low, you can always add a small pump that's made for this application. But give it a try, my RO/DI and tank is probably 20 feet from my tank with no ill effects.
 
Sounds great! I am probably only 15' away, but 25' would definitely be the maximum after plumbing through the floor joists and such.
 
I just finished installing it and it works great! It was also a breeze to install, it only took me about an hour and two trips to home depot. I have read peoples comments on here about getting a more expensive RO/DI unit because it will be better but I don't see how it would be. I have a TDS of about 336 from my municipal water, 22TDS after RO(will improve when I get a 90GPD membrane as opposed to the 110GPD membrtane I have now) and am getting 0TDS after the DI. I couldn't ask for much more.

The system only cost me $115 USD and came with everything I needed(faucet, tank, 6 stage RO/DI, all filters and fittings and easy to follow instructions) except a fitting I needed to hook it up on an odd sized tap. My wife is enjoying the fresh RO from the tap and I have already made about 4 gallons of DI.

I also bought an inline TDS meter as well as a water pressure gauge.I get about 85PSI after the first three stages and before the membrane(where it reccommeded I put the meter), is that good? 85PSI doesn't seem to bad, but I am still getting alot of waste. The water is very cold, so I am going to try putting about 25' of hose through a bucket with an aquarium heater to see if that improves it even more.
 
After owning one of the 'cheapo eBay' units for almost two years, I agree that I don't see a reason to buy a name brand. The filters may not be the 'best' but after 6 months and you replace them with top of the line filters, there's really no difference.

There ARE two things, however, that you may want to consider as upgrades if your unit didn't come with them. One is the 90 GPD membrane you mentioned already and the other is a larger capacity, verticle DI cartridge. The DI cart that came with my unit was inline and laid on it's side. When it was used up, I bought an add-on cartridge that came in a standard 10" filter housing. The DI cart inside is refillable so it saves in that way too. The new DI cart also holds something like 16 ounces of media so it'll be longer between refills. I got the add-on from Buckeye Field Supply. They're also a good source for filter replacements.

With regard to pressure, I think 85 PSI is good. I don't recall the exact number but it seems to me that you need a minimum of 75 PSI.

The cold water WILL have an effect on the efficiency from what I've read. I'm considering adding a mixing valve to mine to add a little hot water to the cold to get the temp up. Since the water sits in the tank until needed, the temp will change anyway. Also, for use in my tank, I have to add a heater to my mixing container to heat up the water so warming the incoming isn't a negative.

Your wife may not like the warmer water but she can add ice ;)

Lastly, a lot of waste water is normal for all RO units. Only a small percentage of the water makes it through the membrane. If you do some searches, people have come up with some creative ways to use the waste water.
 
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I can tell you that the best bargains out there in RO/DI are almost certainly from www.airwaterice.com. I have the Typhoon III and it is awesome. I have it installed in my laundry room and have found that the pressure on the washing machine hookup cold tap is outstanding! I run this to a Rubbermaid Brute (grey color, food safe) with a float valve and it works like a charm.
 
Thanks for the advice Troy, I will look into replacing the DI cartridge when it needs changing. I also need to look into exactly what the water temp is. I remember reading that 78 is an efficient temperature to make water at. I will try that then start looking into creative ways to use the waste water. Since it is mounted above my washing machine, maybe I will make the DI water on laundry days and use the waste in the washing machine. There is nothing I can do about the waste that is made when we use the RO water for drinking but I am sure that won't add up to much anyways.

Also, Keeperofthefish, that's where I have mine hooked up;to the cold water tap going to the washing machine. It seems to have the best pressure in my house. I am going to go buy a plastic cylindrical container they use for commercial applications to store the water. That way I can put it out of the way and have a tap and float valve easily installed. I believe I can get a 40 gallon one for under $80 CAD.


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<a href=showthread.php?s=&postid=6743940#post6743940 target=_blank>Originally posted</a> by swenard
II have a TDS of about 336 from my municipal water, 22TDS after RO(will improve when I get a 90GPD membrane as opposed to the 110GPD membrtane I have now) and am getting 0TDS after the DI. I couldn't ask for much more.

Just a little advice...

IMO you should get a 98% rejection membrane (such as a dow filmtec) (I'm not sure of the what the rejection of the 90 gpd you referred to above that you intend to get) a 98% rejection will reduce you TDS entering your DI from 22 down to 7-- and will allow you DI resin to last 3 times longer...

Case in point, mine takes my 411 ppm TDS raw water down to 8 ppm..... the DI resin will take any water TDS (pretty much) down to 0... it just lasts longer with lower TDS water entering it... so to save money on DI resin, you want a good RO... especially if you have high TDS water like you have...

I do agree with the above... to save money on replacing resin, get an inline refillable cannister-- airwaterice.com refills are about $8 if you have a refillable canister already...

I know everyone can get 0 TDS water with even the cheap units... but the ones of us with high TDS water will save money pretty fast with the better units (like the Typhoon III).... resin does need to be replaced when exhausted...so there is an ongoing cost associated with all of these units.... the better RO you buy, the lower your DI resin costs over the life of the unit...especially apparent if you have high TDS raw water.
 
Your post makes me laugh, because you say the better Ro units will save money in the long run. How? They are the exact same units, except they have different membranes installed.The membranes will be changed to the same ones that come in the more expensive units down the road anyways, Once they need replacing.

So if you're saying, "us with the better RO", means RO membranes, I agree. I am currently getting a little bit high of a TDS after the RO membrane right now and know it could be improved, to prolong the life of my DI resin. If you mean different equipment, which I assume you do since you mentioned the Typhoon, you're definitely wrong as there is little physical difference between the two.They have an RO only unit at home depot for $699, does that mean it is the best?


Also, how many people have compard the two? I have read many posts from people who have(on other message boards) and they say they noticed no difference between the cheap units and the expensive ones. I even consulted one of my customers(engineering firm) who specializes in industrial RO/DI units for food and pharmaceutical manufacturers. He verified that all RO equipment is 99.9% the same. Water flows through plastic tubes, through a membrane, then through a DI resin. How can you mess that up.

I could easily afford even the more expensive units, but I choose not to, based on professional advice from an engineer and me being the cheap-a** I am. It seems most people who spent more money on their units seem a bit bitter about others paying less and want to justify why they spent more money. I see it with all manner of equipment on this board, skimmers, RO units, lighting, etc. Some I agree with, some I don't.

I wouldn't mind doing my own test too. I want to get another RO/DI unit for my office water cooler/tank, so I don't have to lug water with me from home. Also so I can stop paying for Culligan water to be delivered, which is a rip-off at $9/jug. Maybe I will get one of the Typhoon III's and hook it up at home beside the Cheap Ebay unit for awhile and see how the results come out. If I am wrong I will gladly swallow my pride and post it on here.

Also, sorry if this post seems argumentative, I do know you are *trying* to be helpful,but I enjoy debating topics I feel confident on.

:)
 
You obviously need to look closer at the various units.
There are major differences between some of them. The $199 spent for the Typhoon III is a great value compared to the $100 to $120 spent on some of the others. The cost of upgrading to a true DI filter over the hollow tube some call a filter is $38 to $50 all by itself. Now throw in a TDS meter, pressure gauge, solid carbon blocks(and not granular taste and odor filters like some provide), Dow Filmtec 75GPD 98% rejection rate membrane(not a 100 GPD 90% nano filter or a no name Chinese knock off that claims to be made in USA, maybe Usa China), auto shutoff valve( some don't include this, DI bypass valve...... the list goes on and on. You can very easily see the value is there. I live in Arizona and expewrience TDS levels that sometimes exceed 850 so the better membrane and DI filter are worth their weight in gold to me. With the high quality prefilters and carbon blocks that also act as sediment filters too my membranes last much longer than with my old setup which only lasted 18 months tops on a membrane.
 
<a href=showthread.php?s=&postid=6750227#post6750227 target=_blank>Originally posted</a> by swenard
It seems most people who spent more money on their units seem a bit bitter about others paying less and want to justify why they spent more money.

Not me.. I bought my spectrapure unit used for $75 off a local reefer leaving the hobby.

I'll try to keep this short and concise.

Any unit with a DI stage can produce 0 ppm TDS water as long as you don't send the water through them too fast (even if your RO membrane is ruptured). The ongoing cost for all the RO/DI units is in replacing your DI resin, it can only remove so much before its exhausted. The better your RO stage, the longer your DI will last.

Now if you have high TDS raw water.. you will recoup the costs of a more expensive unit faster by spending less on replacing your DI resin..... if you have lower TDS raw water it just takes longer to recoup the cost of the more expensive unit.... it depends on your water usage, and how high your TDS in your raw water is....

The point we try to make to everyone is that it is cheaper over the life of the unit to run the Typhoon III (upfront + resin refills)....

If you want to spend more money over the next several years for DI water then get the chinese unit....
 
I stil don't see any evidence of people comparing the two. Not even any anecdotal evidence. It sounds like you're just repeating something someone else told you. As far as a unit coming with extra things, auto-shutoff water pressure gauge, TDS meter,etc. I still paid less for my unit after adding both a dual inline TDS meter and water pressure gauge. It came with an auto-shut-off.

As far as the better filters go, The Typhooon might come with better filters, but they all need to be replaced anyways and can be added to even the cheapest unit down the road.

Off topic - Also, just because something is made in China and is made cheaper does not necessarily mean it is a crap product, I import stuff from China all of the time and it is made to my specifications, not theirs, similiar to most items sold by other North American distributors. I have even seen a name brand product beaing produced and on the same assembly line, perfect copies being made with a different manufacturers name and sold for 1/4 the price.
 
Swenard, you essentially proved it with this post...

<a href=showthread.php?s=&postid=6743940#post6743940 target=_blank>Originally posted</a> by swenard
I have a TDS of about 336 from my municipal water, 22TDS after RO(will improve when I get a 90GPD membrane as opposed to the 110GPD membrtane I have now) and am getting 0TDS after the DI. I couldn't ask for much more.

This isn't an anecdote, its your words.

You are getting about 94% rejejection from your RO stage.... 336 ppm in, 22 ppm out.

I have a 98% reduction unit, 411 ppm, 8 ppm out.

Do you NOT agree that my DI resin will produce more 0 ppm water then yours before the resin is exhausted?

Is the cost of yours still going to be less after you add a new membrane?? which you say above you plan on adding...

believe it or not, I'm trying to save people money.

For some people IMO, if they have low TDS raw water-- the other unit might be a better choice since it will take several years to recoup the cost...

You would have recouped it fairly fast...

RC needs a RO/DI costs calculator....

Good luck....
 
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