RO/DI Setup

[dt34]

I'm new so if this is the wrong place for this please forgive me. Anyway, I bought a RO/DI unit off ebay a year or so ago and finally got around to installing it. Its seems to be working fine but I have one question. There is a shut-off valve on the waste line and I am wondering if that to close the system when not in use or if it is to reglate the rate the waste water flows. So far I have left it wide open, is that ok or should I close it partially? Also what should I use to test the water to make sure the unit is functioning properly?

Thanks
Dustin

 

[Anonymous]

Hi Dustin, and :welcome:

I'm not sure about that shut off vavle. My RO/DI did not come with a shut off valve.

You should use a TDS meter to test your water. Hanna is a fine brand and most of our sponsers carry them. They cost about $25 and are well worth the money.

Louey

 

[dt34]

Thanks Louey

I guess what I will do is get water from my lfs until I can get this sorted out (my rock will be here on Thrusday). I think I have it set up correctly but I can't be 100% sure. I have a attached a picture of a unit similar to mine. In front is the valve I am talking about.

[/img]

 

[SnowManSnow]

Hey,
The shut off valve should be used more as a regulator than a complete shutoff. You should shoot for about 1 part of filtered water to 3 or 4 parts of waste water. In other words, for every gallon of pure water you should produce 3 - 4g of waste.

I know it seems excessive, but the waste water isn't just water that doesnt go through the filtration process..it actually serves as a vehicle to REMOVE the waste from the water. SO....if you run 1 gallon of pure water through the system and have 1 gallon of waste the TDS meter will read a higher TDS in the waste water than what was origionally in your water before you began to filter it, whereas the "purified" water should read considerably less. (So don't drink your waste water or run it back into your system).

I hope I've helped a bit.

B.

 

[pcragg]

This is a quote from the ebay site.
"Ball Valve Restrictor & Quick Membrane Wash.
Position "close" to force the water to go through the membrane
position "open" to allow all water to pass over the membrane and washes it off."

I don't know if forcing the water to go through the membrane is a good idea.

 

[scuba_steve]

there has to be back pressure on the membrane in order to produce purified water, ie forced through the membrane.