If you are on the road during freezing weather, make sure the water pump is shut off and then open the low point drains and leave them open until the next CG. Any water left in the lines may freeze, but it won't expand enough to damage anything. Then when you arrive at the CG, turn the furnace on right away.
If you don't want to insulate the outside water line or are unsure about the next CG having water available, keep the fresh tank nearly full, it and the internal lines are less likely to freeze. Same thing if daytime temps are above freezing but overnight temps will be below freezing. then top off the fresh tank as soon as you stop, then store the outside hose and use the fresh water tank for your overnight needs.
Texas Baptist Men-Retiree Builders member since '01
13 Silverado 3500HD D/A, 2wd CCSB srw, custom RKI bed
11 Cruiser CF32MK