Update... 11/30/08
I took off the sides to reach the controls and it became all too clear what the issue was... Squirrels!!!! As I mentioned it just turned cold and the little buggers were storing a winters worth of nuts and pine cones however, I guess that was not enough as they also chewed on the wire loop from the control box to the pumps. After I cleaned it all out I found that although the cornes of the external walls were square the underlying frame was not!! Each corner was cut back about eight inches exposing a nice triangular space about six or eight inches across for the little stowaway's to enter unaccosted!! So, I stuffed the holes with steel wool and then backfilled from the inside with expanding foam.
Today I watched as the little guy went from corner to corner trying to figure out where the door went?? It has only been 24 hours but so far so good... I was tempted to put up a small sign for the little guy directing him the neighbor's tub.. he he he...
