Our Oceanis 37 refrigerator has a small tube (maybe 1/4" diameter) from a pan under the freezer to outside the back of the fridge. I presume this is to drain water melting from frost in the freezer, but I can't tell what's behind the fridge to see where it goes. My questions are: 1) Am I right about the purpose of the tube? 2) Where does this drain to? 3) Are there any low spots/loops that I would need to be concerned about freezing over the winter or is it a straight run?