With the search feature at the top of the page, and "cold weather camping" you should find a number of discussions.
Bottom line is if you do not have an enclosed, heater underbelly and temps get into the mid 20s and down, you are going to have freezing water lines. There are some methods to help prevent that including filling your water tank and using that but again if the lines under the unit are exposed, it take a major effort to avoid freeze.
We often camped at 8000+elevation with a heated under belly and still had issues at times. If you do have heat you will need to keep the propane heat going to keep heat to the underbelly.
https://www.jaycoowners.com/forums/f...ing-80818.html
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