Getting the most out of your RODI system

[RTMA]

Guys,

Now this may be new news to you, or maybe something you usually do, but it was new to me as of March, but it has made a difference for me.

What was happening was that I was going through DI pretty quickly so I had to find out why. When I ordered my new RODI system, I made sure I got enough inline (3) TDS meters to read the incoming, post RO and post DI water.

What I had found was that my RO system would not work properly when I started it up. I had found that while it was off, high TDS water was somehow getting past the RO membrane and into the DI canisters until a sufficient amount of water had been passed.

Upon startup I saw the TDS of the water heading to the DI canisters read 90+ TDS and then start to come down pretty quickly over the next two minutes (until it reaches the 7-8-9 TDS mark a few minutes later), however sending 90 TDS water at any time through DI resin will deplete it very quickly.

So what I did was place T from the RO output to the DI canisters. I then placed a valve after the T and fed that to my DI system, allowing me to shut off the DI canisters. I placed another valve on the other side of the T allowing me to run the RO system alone and drain that water into my sink.

So now when I make water I drain the high TDS water and once I see the TDS between 7 and 9, I turn off the valve and open the valve to the DI canisters. This allows only low TDS water to enter the DI system.

For me the difference was so profound. I used to use up a canister of DI in a month, now it has been 5 months on my 180 and I have yet to use up 1/2 a canister.

So if you find that you are using DI quickly, draining the RO water for a few minutes may help. Also getting an inline TDS meter is well worth the price.

I also have added the flush kit and do flush occasionally. I haven't seen the benefit as of yet for that, but I think it may be the reason why I can get 9 TDS out of the RO and sometimes get 7 with the same TDS of the incoming water. I previously did not believe there was any need to the flushing, but I am starting to rethink that.

Hope this is helpful. I'd be interested to hear how fast you guys go through DI and it you have had similar issues.

 

[Collinrb]

Installing my RODI tonight for the first time. Will keep your suggestions in mind. Thanks for the post

 

[srusso]

Its crazy but the water coming into my house is so clean, the tap averages only 20 - 60 TDS, yes... from the tap! So my DI is now going on almost two years now! The water going to the DI is always 2 TDS and zero coming out. My kit came with a flush kit and have flushed the system before each use for about 30 seconds, and if I remember after each use for about the same as well.

Making RO/DI for me is a manual process, in that I start the system. Make about 20 gallons at a time, takes about 4 hours. So I set I timer and turn it off about 4 hours later.... Yes this dumb @$$ method has flooded the basement way to many times...

Also my system gets 90psi, so the house also has great water pressure.

 

[Below Radar]

I have had a Vertex 200GPD for the pas 2 months and I just started reading a few ppm on my meter. This happened only after I ran it long enough to fill my tank(210 total gallons). Anyway, point being, there is an auto flush for 30 sec before it goes to DI and it flushes for a specified time every 2 hours. Good idea to save your resin. I'm a little bummed mine only lasted 2 months...maybe 400g of good water.

 

[terahz]

Good tips Joe.

After I moved last month, the lower water pressure killed my DI. It was only ~30PSI and I guess the RO membrane wasn't doing much. Got a booster pump from BRS to get to ~95PSI and daaang, what a difference. Much cleaner water out of the RO membrane and much much faster.

 

[JoeBellz]

what brand system do you have Joe? I have a SpectraPure 90gpd unit that is super efficient on filter replacements. I do about 25g a week for WC and TO, my PSI is around 50 or so. I'm fairly certain I have only changed filters once over the past 2+ years, still getting 0 TDS with no issues to the tank. I also never trust my in-line TDS meters and use my handheld HM Digital TDS-3 meter which I love: http://www.amazon.com/HM-Digital-TD...ie=UTF8&qid=1343331471&sr=1-2&keywords=hm+tds

 

[srusso]

Good tips Joe.

After I moved last month, the lower water pressure killed my DI. It was only ~30PSI and I guess the RO membrane wasn't doing much. Got a booster pump from BRS to get to ~95PSI and daaang, what a difference. Much cleaner water out of the RO membrane and much much faster.

Yes, BRS has a video that explains this. Water must be forced through the membrane, if water doesn't having enough pressure to force, some of the super tiny holes get clogged. Without a flush kit the issues are further compounded. Soon enough the water will have ripped though the membrane and sending full tap all the next inline filter, normally a 5 micron filter... I believe they even have a minimum PSI for their units. It was the reason I got the system with the gauge.

 

[clittrell]

I use the Vertex puratek and really like it. It has nice features including automatic flush and a booster pump and built in TDS meter. When it starts and after so many hours of production it flushes the unit. I added TDS meters after each stage for a total of three. I also found the high TDS coming out of the RO section on startup. I use my Apex controller to turn it off and on twice when ever it is time to make water. This flushes the RO membrane and the TDS meter reads 1 or 2. The Apex fills the Water tank twice a week automatically. I think you should always flush the any unit before you start making water.

 

[scolley]

I use the Vertex puratek and really like it. It has nice features including automatic flush and a booster pump and built in TDS meter.

Auto-flush. THAT is a cool feature! The equipment geek in me is now operating in Full-Envy mode.

 

[Kdocimo90]

Interesting discovery. Definitely take note of this when making some water next time. Thanks!