While I have not helped with the install yet my buddy wants to put solar on his trailer, his fridge vent is on the side as well. From what I have looked at so far I'm thinking of running the line down the fridge vent then drilling a hole in the bottom of the fridge frame area to pass the wires into the water heater compartment then another hole in this compartment to get the wires under the trailer. Its either do this, drill a hole in the roof to get the wires into a front bedroom closet or run about 30 extra feet of wire and use the black tank air vent. Shortest route is the hole in the roof for about 20 feet of cable, fridge vent will take about 30 feet of cable and vent run will be around 50 feet since its the opposite direction from where we need to be.