I had a problem with mine overheating during the summer. It kicked out the overload a couple of times. Also, I noticed a marked reduction in the suction in my system. What it turned out to be is as follows:
I installed my piping in my attic to avoid having to take down everything I already had hanging on the walls. Well, being up in the attic, I figured the pipe would just lay there, so we didn't put a screw in each fitting as we now recommend. When I finally crawled up in the attic, I found that one of the pipes right at the cyclone had come out of the Y and was about 1/2" away from the fitting. That explained the overheating because it was sucking the maxium amount of air all the time and my small closet was getting warm. As soon as I fixed the leak, the problem went away.
Ed