If you have an outside shower it is at risk. I added stops and drain valves so I could isolate & drain it. many rigs fail to provide the valves & drains stock, mine was no different so I did it myself.
Our belly is insulated with heat ducted to the tank area so all is good even in the mid 20's. We just fill the tank & run off that if cold is an issue. I drain and stow the hose once the tank is filled. I also keep the sewer valves closed and dump every 3 or 4 days if stationary and on arrival if moving. Running near empty risks a freeze up so I avoid it.
