DIY Evaporative Cooler

I've had this running for a couple of weeks now and I'm pretty happy with it. It's keeping my res 4-7 degrees cooler than my air temps. The higher my air temp, the higher the spread. My air temps are running 69-79 degrees. My res's are three 96qt heavy duty styrafoam coolers which I'm sure improves the efficiency.



It costs me less than $20 to build using pvc parts from the H/W store. I did have to experiment with hole size and you have to set the ball valve just right to get proper water flow. My brother built a bigger version of this for his swimming pool and it did such an amazing job cooling his pool I figured I'd give it a shot and it's worked well so far.

looking good that m8, job well done

Whats the science behind this exactly, im very intrigued.

As the drop is falling, part of it evaporates which draws the heat of vaporization out of the remaining part of the drop, cooling it off substantially.

Here's a chart showing the maximum cooling effect possible for a given temperature and RH.

The nice thing about this for me is that my RH is running a little low anyway and I need the cooler res temps. You do need to top off more often and you wouldn't want to do this with tapwater if your PPMs are high like mine. I do complete changes with tap but I top off with RO water.