This is my first winter living fulltime in my Heartland Wilderness travel trailer and I'm in CO. Because I'm staying in one place, I underpinned with foam insulation board and I put a heat lamp under the kitchen area and another under the bathroom area. I leave the bathroom cabinet and door open at night and the door under my kitchen sink where the hot water is and I drip the hot water. I have heated water hoses and the spigot coming out of the ground is also heat taped. I don't use my propane heat because I can't afford to fill propane bottles every few days which is why I am using heat lamps under the trailer. I have an infrared electric heater that keeps it quite warm inside. With all that being said, my water still froze last night when it got down to 17. I'm wondering if the outside part of the hot water heater that has the overflow valve could be the weak point? How would one insulate that, if it's the culprit? Thanks for any insight that you can give.