bought used rodi (im new to rodi) advice wanted.

[ddc0715]

So picked up a 5 stage rodi on the cheap 140 .
heres what i know.

1. Tap water tds is 122 with a pressure of 68 psi.
2. Test run of rodi water produced a tds of 0 seems to flux 1-2 depending on the container I fill (is this normal?)
3. Waste tds is 120.
4. Pressure into the membrane is 54 psi.

1 minute water test was 150 ml of product water and 750 ish of waste water.
Water test= 4.25-4.5 g’s for 1g of water.

If you look at the pics of my set up how could I improve the ratio of 4.5 to 1
and most importantly did i get a good deal?
should i replace anything since i bought it used?

 

[saltyfilmfolks]

Hi.
Replace all of the filters. They sound good and you’re getting good numbers but.

Use a second glass and fill it with the new water. Fill it and Rinse it with the new water and fill it again then test the rodi.

You could use a tiny boost for the psi but I’d start with new components and go from there.

It feels like by your tap tds you may not have a lot of chloramine so you could save up for a second RO membrane and improve the ratio.
Do check out Melev and BRS for info on rodi.

 

[ndrwater]

What he^^^^^ said.

 

[miyags]

Did they tell you how old the unit was?Membranes usually last 5 year.Did you replace all 3 of the lower filters and the di resin.

 

[redfishbluefish]

I'm looking at what I believe is the sediment filter....all the way to the left....and that looks darn clean to me. That tells me this thing hasn't seen much water (or water that was darn clean). I wouldn't change them yet. After about a month, mine is the color of coffee with cream.

I'd also consider picking up a dual in-line TDS meter and put one sensor after the membrane and one after the DI canister. Tells you whats going on with your membrane and DI resin. Should be able to find them at around 30 bucks.