RO/DI water temperature
 

I just ran my cold water line into my RO/DI unit, is it ok? I heard that you need to run water temp around 79 F. Is it true? Why can't i just run cold water through?

I only use cold water though my RO/DI unit.

I only use cold water through mine. Have never had any issues mixing with it.

Mine is also run on the cold water line; however I do run about 30' of hose into my sump (coiled) before it reaches the unit. The water is warmer that way.
I've been told that cold water will lessen the life of the membrane.
Since I ran the extra line, i find my output is greatly increased as well.

no problem with cold (but hot will wreak the membrane) but what the 77° temperature is about, is that's the water temp the membrane's output is spec'd at. Colder less output, some idea for pressure.

Some links here that give an idea of roll off.

ok i see clear pict now.
Thanks all

airwaterice.com where I bought my unit says that for every 1ºF below 77ºF you lose 1.3% For me this was quite noticeable so I now have my unit plumbed to both the cold water line and the hot water tank. Another option is to coil up and submerse several feet of your input line in a bucket full of water with a heater.