Hello Forum! I am a freelance traveling musician/teacher and I purchased a 1991 Mallard Sprinter Class C. She's showing her age but I just call that my built in theft-deterrent system. I've learned more since I bought it than I knew before buying it, but I have really enjoyed the challenge of living full time. I've developed some handy skills in a "trial by fire" method. I love it for my travel, and as a trombonist, it's great to always have a practice room (people don't care much for trombone in hotels). I am towards the end of my doctorate, and I plan on writing my dissertation at the dinette.
I am currently on a gig in Green Bay in January. Last night temps got down to 6 degrees. I have done quite a bit to make this vehicle winter-worthy (pipe insulation for water lines, weather stripping for all windows, foam insulation pieces for anywhere I can put them. I have removed the seat cushion that would cover the water pump and tank, left cabinet doors open, extra curtains to cover the door, made a cover for the stove vent)
I have not yet done anything with my lines outside the vehicle so I am concerned for my grey and black water tanks freezing. I am boondocking (thus not emptying daily, but also not hooked up to water/sewer lines). With last night being so cold, I just left the vehicle running figuring the exhaust would help keep the underside of my vehicle warmer. I poured some RV anti-freeze down the drains to mix in with a small amount of waste but I realize thatís a small step. There was a small freeze on the right side (no kitchen sink or shower for a bit, but thawed and all works fine now thankfully!).
Here are my questions (for those of you still reading- thanks!):
At what point should I feel OK that my tanks wonít freeze? Iíve read 20 degrees seems to be a pivotal threshold, but Iíd rather not guess wrong on this and err on the side of caution. I have researched heat tape, tank heaters, "freezeless" lines, etc. I donít have resources to improve anything on this trip so I have to make due. I burn a gallon of gas every 2.75 hours when I idle so itís still cheaper than a youth hostel for an evening. I realize the environmental detriment still outweighs a cracked black water tank. Can anyone weigh in with more insight? Thanks in advance and safe travels!