Since I'll be spending the winter in my Cougar in northern New Hampshire this year, I thought I'd need to make a few improvements. When I pulled the forward coroplast down to install Ultraheat tank heaters on the bathroom black and gray holding tanks, I was surprised to find absolutely no insulation or ducted heat in that area, which is located below the forward basement. Knowing that I'll have many nights below zero here this winter, I figured the tank heaters alone wont be adequate to prevent the dump valves from freezing, even though they are located in the enclosed underbelly. Based on a post from this forum from someone who added a fan to circulate warmed air near his water lines, I did the same to add heat to this area. I found a fan on Amazon that moves a decent amount of air, draws very little current, is designed to run continuously for years, and is very quiet. It attaches directly to 4" sched 40 pvc.
I slit and pulled back the carpet, cut a 4" hole directly above the center of the dump valve assembly, and slipped a 4" to 3" adapter into the hole. The fan is connected to that with an elbow and short length of pvc. The fan now pulls warmed air from the basement area, and directs it onto the dump valve to prevent any freezing. It also provides positive warmed air exchange down the length of the underbelly, as I can feel the air exhaust at my water line penetration alongside the water heater, which is about halfway down the unit.
The furnace should be sufficient to provide enough warm air in the basement to supply the fan, but I also have a small oil filled radiator to supplement if needed. I've had several nights in the *20's already, and all is working well so far.
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