Anyone here using a "swamp cooler"?

[snakeeyes]

My garage is a 2400 sq. ft. metal building. It has no insulation and gets pretty hot inside during the summer months, to say the least. I keep a scroll fan running during the day to circulate some air, but I am worried about the long-term effects of not only the heat but even moreso the humidity on my cars, motorcycle, tools, etc.

I am considering purchasing either a very large, belt-driven fan (like they sell at Lowe's or Home Depot for around $250) just to move the air around even more, or splurging for an evaporative cooling unit from a company like Port-a-cool (www.port-a-cool.com). Port-a-cool sells a 48" unit that they claim will create a significant temperature drop in an area up to 3,500 sq. ft.

My question is, does anyone have any experience with evaporative cooling units? Since they involve blowing air across a wet surface, I am concerned that they might actually promote oxidation, rather than help prevent it. I don't want a shop that is 10 or 15 degrees cooler but is filled with a bunch of rusting cars...

Thanks for any input anyone has.

Bob

[JoeLafives]

Tucson and Phoenix are filled with Swamp coolers. They work well in low humidity conditions as they definitely put moisture into the air. They are not usually used when the humidity is high simply because they become inefficient. I wouldn't conceive of using one in San Antonio. (I lived in Houston for several years and as I recall SA was almost as humid as Houston.

You might consider a window A/C unit and an electric fan. This would reduce the humidity and cool better in your climate.

Scott

[mikiec]

As Scott says...

Swamp coolers are best used when the dew point is below 50. The lower the better. Yes, there is some moisture in the air from these units as they do blow air across water soaked pads. Many automotive shops here in Phoenix use them.

Mike

[snakeeyes]

Thanks for the input, Scott. I wouldn't have thought they would be prevalent down here, either (we're not as humid as Houston, but damned close ), but there are several few shops--automotive, florist, etc.--in San Antonio where I've seen them in use and spoken to the owners. As a rule they have indicated that the coolers create a drop of 10 degrees or more on even the hottest days. I'm more concerned about introducing even more humidity into the environment, especially during those months here when it's still hot but (relatively) dry. I don't know enough about the engineering principles involved, I guess, to know if the fact that the air is significantly cooler somehow negates the effects of the tiny water droplets it is carrying...

[wrench]

We had some in our shop in L.R., AR last summer, they did help with temp, (10 degrees or so), but i did notice some rusting on tools I dont use everyday.

[snakeeyes]

Thank you for the replies, guys. I am going to start with a larger fan and perhaps a window a/c unit as suggested. I don't think I need to increase the humidity level any more than it already is around here...