Can I run the RO system outdoors?

RO/DI systems are designed to be used indoors in room temperature conditions. Summer heat and winter cold will do damage. If you can not keep it installed indoors, insulate it carefully to protect it from damage. 

In the summer, direct sunlight will lead to algae issues as well as risk of bacterial growth within the system. Installed in a well shaded spot will help.

During the winter months, many outdoor RO systems suffer damage by freezing, cracking housings, bursting fittings, and rupturing the membrane. Turn off the water, drain the housings and hope for the best, or bring it inside until the temperatures rise above freezing.