We like early spring and late fall camping. As a result, we have awakened to snow several times (up to 4 inches) and have camped - both with and without hookups - several times with overnight temperatures in the 20's. We disconnect our water hose on expected cold nights (if with hookups). Again, if with hookups, I will turn on the "Artic Pac" sometimes. Without hookups, I avoid both the "Artic Pac" and the furnace, as both are heavy battery users. Without hookups we use a portable "Buddy Heater".
No issues to date with plumbing freeze ups. I believe by keeping the living area "comfortable" - mid 60's - the radiated and conducted heat sufficiently protects the plumbing from outside temps in the mid 20's.
2012 Solera "S".
2012 Solera "S"
Calif SF Bay Area