Question bout a ?flush valve? and more

[Jonathan Troutt]

wondering if a flush valve will solve my issue. I get a tds reading of 3-4 that slowly falls to 0 over the course of about 10 minutes of filling a 5gal jug. Im thinking i need to a flush valve.

Also the color changing resin i was under the impression is supposed to change 100%. Mine has changed on top and bottom but the middle has not changed. I am showing nitrates in my ro/di and it concerns me shouldnt my ro/di be pure water with no nitrates?

Im on well water btw and the ro/di unit has been up for about 6months. I use it once or twice a week to get around 5 gallons of water each time. Depends on humidity level.

 

[crusso1993]

wondering if a flush valve will solve my issue. I get a tds reading of 3-4 that slowly falls to 0 over the course of about 10 minutes of filling a 5gal jug. Im thinking i need to a flush valve.

Also the color changing resin i was under the impression is supposed to change 100%. Mine has changed on top and bottom but the middle has not changed. I am showing nitrates in my ro/di and it concerns me shouldnt my ro/di be pure water with no nitrates?

Im on well water btw and the ro/di unit has been up for about 6months. I use it once or twice a week to get around 5 gallons of water each time. Depends on humidity level.

A flush valve will definitely be beneficial.

Any nitrate reading on RODI water is problematic as there should be no detectable nitrates in the filtered water. I would suspect the filter needs changing.

 

[TriggerFinger]

I assume you have the mixed DI resin?? You may be better off getting a single anion and single cation resin beds. Based on your resin color change, it looks like you use one resin more than the other and that one resin may be exhausted, letting nitrates slip through.

 

[KStatefan]

You do not need a flush valve you need a bypass valve to eliminate TDS creep.

Bypass the DI and discard the first product water. My bypass timer runs for 60 seconds prior to switching to the DI.

 

[MTBake]

I do what @KStatefan does.

I added a coupe T fittings with shut off valves so I can turn off the flow of water to the DI stage. I let the ro flow for several minutes before letting it flow through the DI resin.

 

[KStatefan]

I use a delay timer and a couple solenoids.

 

[MTBake]

I use a delay timer and a couple solenoids.

Do you have a link to what you used? I would love to automate this.

 

[Jonathan Troutt]

Yes i would like to see it to. I have thought about adding the a second di and running the two different types of resin.

 

[KStatefan]

The black box at the upper left is a tank level controller. The relay at the upper right is a standard delay relay that when the controller turns on the bypass solenoid is turned on until the time set on the relay expires the the DI solenoid turns on until the tank is full.