I think a compressor would work better, but I've never tried a vac. Every other year or so, our pipes in the barn would freeze because of pockets of water that wouldn't drain properly. I finally put to air valves in so I could blow it down with a compressor, and haven't had any trouble since.
Nimrod has a good point about the mice. My parents have cabin in the mountains. Although it's well built and insulated, they'll still get mice in. A few times, we had to burn the bedding due to mice infestation. They'd get in and chew it into material for nests, and it'd be full of droppings. Now we get rid of any food that not in cans, and put all fabric (clothes, blankets, etc) in tight wooden chests, metal foot lockers, etc. It's a pain to do, but makes it easier to go back up in the spring. Curt