How much waste water does a RO unit produce?

[Wayne]

Hello all I just picked up a Conqueror IV 4 stage Ro unit and I am planning on hooking it up as soon as I can get to a plumbing store. I have been doing some research and I found out they produce more waste then good water? Anyone be able to shed some light on this?

[Milad]

its suppose to be 3 to 1 or something like that. mine is exact opposite, it drips out waste and produces tons of good water but im in north van and my tap water is < 12 TDS

[rjengen]

I'm lazy...the following is a cut and paste...I think you should be looking for a 4:1 ratio though, 4 parts waste to every 1 part of good water. If you're getting more good water to waste, I would say something is wrong with your filter...at least that's what me thinks

"The RO stands for Reverse Osmosis and refers to the chemical/mechanical method of filtering the water. Basically the water is forced through a semi-permeable membrane that allows water molecules through, but blocks most other organic and inorganic materials. This can only happen with a pressure differential from one side of the membrane to another. But the membrane is very delicate and would burst if presented with the normall pressures a normal filter cartridge endures. Thus the water flows across the membrane with only a moderate differential pressure. The second reason for the waste water is that since the pores in the membrane are very small, they clog easily. The flowing water across the membrane also flushes the membrane clean. Even so, most RO units have a method of flushing the membrane with full flow to clean it further."

[PoonTang]

Yes they will generally run from 2:1 to 4:1 depending on the input pressure and temperature.

[fencer]

4:1 with booster pump
8:1 without

[mark]

you can get a valve to adjust the ratio (here), I have mine for 3:1

[Bloodasp]

mine makes about 1 gal RO for 3 gal waste. tried calculating how much it would cost to with filters and membranes and waste water hopefully I got it right, it costs about $0.80 per gallon of RO water produced. biggest cost comes from the RO membrane.

[Wayne]

Hum well I guess I will have to plumb a line into the sink drain. I was originally planning on putting it into a bucket, but after I make 5 gallons of water and have 20 gallons of waste, esshh! Thanks

[globaldesigns]

Originally Posted by fencer

4:1 with booster pump
8:1 without

Is this really true? Can someone verify. If this is correct, I think I should get a booster pump. why waste water!

[Slick Fork]

I get about 3 Gallons waste to 1 gallon pure with a booster pump