If not mentioned somewhere else another easy thing to do is at night open, and/or crack open cupboard doors where piping runs are, thisallows air to flow into these recesses. Most plumping piping on RV's are run in the corner formed by the floor and sidewall. Probably the most vulnerable place for the possibility of freezing, especially on older RV's, is under the shower/bathtub, this area can be a dead air space that only see's heat that is radiated through the shower/bathtub bottom.
Also at night depressurize your water system, leave fixture open so if by a remote chance you experience freezing, there is room for the expansion so pipe won't burst. We turned the furnace down to between 55/60 at night.
We skied out of our Safari Motorhome, which we parked in Ski Area parking lots every weekend of Ski season for years never experienced a freeze up other than on the tank dump piping which was not an issue. Just let it thaw once we came out of the mountains, then dumped.
"Those who stand for nothing fall for anything"
2008 Newmar VTDP - 3330 - ISBXT 350 Spartan NVS
Toad - 2013 Mini Cooper S or 93 Nissan 4WD PU
FMCA F113720, NKK 18573