I finally made the decision and bought the unit, took me 30 mins to install it(I only installed 2 DI units and I hook it up with kitchen faucet), the thing is it leaks everywhere, I tried very hard to screw and it still leaks, I wonder if it happens to you all? I plan buy buy some white plumbing tapes to see if that helps, am I able to do that?

where's it leaking?

almost half of those U shape connection leaks
http://i56.tinypic.com/1q65tu.jpg

Is the tubing pushed all the way into the fitting ? You must use teflon on all threaded joints.

Tubes are pushed all the way down, I now use teflon on all threaded joints, no more leaks, exception I broke one the elbow connector by turning it too hard:redface:

Don't feel too bad!

It is a ok unit the number of gph or gallons per hour is depended on the model number just know what you are. Buying because some don't take out the chlorine , also don't p,an on using the water u are getting within the day to fill a bucket it can take up to 5 hr, besides that stuff it is a bang for your buck that I coolant say no too hope I've been a help

I'm not a plumber, but I did most of the plumbing in my house when we built it, and have done several underground sprinkler systems. Never installed a RO/DI unit, but I can tell you for threaded joints, don't use that white tape.

Use the the yellow gasfitter's tape, it comes on the same type and size of roll as the white stuff, but it is much thicker and works so much better. You end up using way less of it too, when wrapping the thread, just make it one tape thick.

You can buy it at pretty much all plumbing supply places.

I'm not a plumber either but I'm curious, is this "Yellow gasfitters tape" potable safe?

Lol, I hope so. A plumber friend of mine says it is, but truly I don't know. Most plumbers I have talked to (I would talk to alot of them while waiting in line at the plumbing wholesale supply place, me being the only non-plumber) only use the yellow, they all said the white is garbage.

In my opinion though there is a big difference between what can be used on a thread under water and what can be used in a "dry" thread.