Camping in sub freezing weather

Deb and Ed M wrote:
Same for us - even though RVs boast about "heated tanks" - most dump pipes and low-point drains are still exposed to the cold. We regularly camped in sub-freezing temps as we traveled from Michigan to Florida in January. Our black and gray tanks were exposed to the cold (no heaters) and we never had any problems as long as ample antifreeze was dumped down the drains. Obviously, we used the campground showers.

That very much depends on the RVs; a fair few do have the dump lines (and low point drains, etc.) enclosed with the tanks and the rest of the plumbing. Plenty of others do not, of course.

I have camped in sub-freezing temperatures in my class C without plumbing difficulties. The dump valves and pipes for them are in the same (nominally heated) compartment as the waste tanks, and the valves for the low point drains in the heated space as well. It's not really set up for extreme cold temperatures, what with having only single-pane windows and so forth, but is quite satisfactory for at least occasional winter usage. I've had more annoyance from the results of road much and road salt causing the step mechanism, compartment door thumb latches, etc. to bind up and give trouble than anything else.