Ask the Expert Question-and-Answer Archive

by Ron Joseph

March, 2004

Heat Reflecting Paints

Q. I have an electronic enclosure mounted in the field approximately 84 inch high by 74 inch wide by 24 inch deep. It gets quite hot in the dessert and in local California areas.

When the computers mounted inside the cabinet get to hot they don't function. We would like to know if the IR portion of the radiant heat can be reflected by a paint on the outside of the cabinet.
This is a steel cabinet. What would you suggest?

A. Typically, people tend to use high gloss white paints to reflect heat. You will often see large tanks in a chemical plant painted white, and the purpose is to keep down the temperature. I don't have any technical evidence that white paint is the most effective material for lowering the temperature in the enclosure, but I base my opinion solely on anecdotal information.

You wrote about IR reflectance. Military camouflage coatings are formulated to have high IR reflectance, but I have never heard that they are effective in lower the temperature in an enclosure.

I have also read about ceramic coatings that insulate against heat. The following article might be helpful: http://www.hytechsales.com/low_eroofpaint.html