Yup condensation, we used to have to crack a vent or window in the winter, especially with two adults and a dog inside in the winter, especially when we run the furnace. It is amazing how much water a human generates just by living.
Power jack, if it is hooked up right try wiggling the fuse, or even replacing it, that is area that causes issues right regular. Do you have a blade type fuse or the glass tube style? If you have the old glass tube style I would swap it out for a marine grade blade style holder.
Hole where the pipes come in? Pack it with bronze wool then spray Great Stuff in there.
Aaron
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