RO/DI question
 

Are all RO/DI units really waste so much water, coming out from waste line from RO membrane? Can i just install a valve at the end so that i can shut it off.

thanks,
teddy

No you can't shut the waste water off. If you do, all the impurities you are trying to get rid of, will attach themselves to your RO membrane and clog it. The waste water flushes these impurities away.
The membrane is the most expensive part of the system.
Some people contain the waste and use it for, clothes washing, toilet tank water, watering the garden. Do a search on this board and you will find a lot of uses in one of the threads.

My Vertex Puratek RO unit came fitted with a valve on the waste return line. I suppose you could purchase one and plumb it in. What brand do you have?

think BWi has a zero waste unit

You can also buy a kit that allows you to run your waste water into your hot water tank. I personally use my waste water to cure my DIY frag disks.

the brand is spectrapure 90..i read the manual and said that it has to have a 4:1 ratio for waste versus production.