Jestersix

Deionization Resin question.

Srt4eric

Vice President
BOD
I have an ro/di system that has a 5th stage Deionization Resin thing that I'm supposed to change when the resin completely changes color. How often are you all changing that resin. I just use mine to fill up 5 gallon jugs and I've accidentally left in on over night a couple times. It seems like I'm changing this stuff often. I know leaving it running for 12+ hours doesn't help.
 
I have an ro/di system that has a 5th stage Deionization Resin thing that I'm supposed to change when the resin completely changes color. How often are you all changing that resin. I just use mine to fill up 5 gallon jugs and I've accidentally left in on over night a couple times. It seems like I'm changing this stuff often. I know leaving it running for 12+ hours doesn't help.
This depends on so many different factors. What is your TDS going into the resin? Do you flush your RO membranes before use? On startup, do you divert the water by the DI resin until the TDS drops? What is your water pressure?

Also there is some evidence that you should actually change it when about 3/4 of it has changed colors.
 
I use a dual tds meter to check input and output tds. Di resin is what I switch out when I see tds going over 0 and the color has changed.

Meshmez has some good questions to help figure it out in a more complete way. RO flush and inline tds meter may be worthwhile upgrades for your rodi setup
 
Single stage can get used up pretty quick, especially if you aren’t flushing, and not diverting all the high TDS water first. And if you arn’t running your RO at a high enough PSI
 
That's just the startup tds creep though. You should also flush your ro membrane. Can you post a pic of your system?
20200913_185143.jpg
 
I need to upgrade.
Yes, I was going to recommend that. Long term you will probably save money, plus get better performance.

On mine I have this flush valve on my waste line. It bypasses most of the water from the ro membranes. And helps flush it clean.
20200913_190714.jpg


I also have this valve that allows me to bypass my DI resin. When flushing and during tds creep (each unit startup) I bypass the DI resin and dump the water to the waste drain. Once tds drops, I switch it to the DI resin, and collect the product water.
20200913_190800.jpg
 
As to the above being a good deal, if you’re handy it is not difficult to plumb in an extra cartridge and do some rearranging. If you’re not then get exactly what you need up front.
 
Back
Top