I willing to put money on the fact that you probably had some wires touching and when you cranked it, the resistance got too high and the reciever went into protection mode. I've done this myself on my old reciever. When you moved it to the window where the fan was, you moved the wires and since they were no longer touching, you can now crank your reciever. There is nothing wrong with your unit. Stories like these are how overheating rumors are started
