This question will apply to both staying full time in the van or having the van parked at the house hooked up to shore power like we do.
We haven't winterized the van nor do we plan on it since we use the van at all different times of the year no matter the weather. It's been around the low 20's on and off for the last month here. As I've mentioned in other posts, I keep a small ceramic heater plugged in to keep the inside of the van warm at night while plugged into shore power here at the house. Mostly to keep the battery warm but also to keep the pipes inside the van warm also.
My question is this. Since we have no plans on winterizing the van, it is supposed to get down to 9 degrees next week and stay cold for the foreseeable future. We plan on taking a few short trips in the van during this time. From everything that I can tell, all of the plumbing is inside the van with the exception of this one small hose leading to the cassette toilet.
Up to this point in time I've kept two very large, thick towels inside the door where the cassette toilet is to keep that area "somewhat" insulated.
I realize this is not a perfect solution but it is better than just cold air circulating around the inside of that area. The door that you open to access the cassette toilet is not very thick nor insulated very well at all. So no matter if we are actively staying in it or not, that small hose will always be exposed to cold weather.
Is this something that I should be worried about? If so, how do you insulate yours when it gets cold outside. I've seen plenty of videos of people taking these things to well below zero and have never heard anyone mention them freezing up. But since it is the only pipe that I know of that is actually outside of the van, it just seems like it has a better opportunity to cause issues than any other part of the plumbing when it gets really cold. I suppose I could be overthinking this. Just curious.