smkettner wrote:
... Outside shower is always suspect.
True- for that reason I added an isolation valve for it.
Not sure how other RV's are made, but my TC has factory valves to isolate the hot and cold feeds to the outside shower. The city water inlet did not. I added a valve for this water input line to isolate it.
For winter preparation (after summer use of outdoor shower and city water inlet) I will fully winterize the domestic water. Once the system is full of RV antifreeze (RVAF) I will then close the isolation valves on each of the shower hot/cold and city water inlet. I leave the camper this way until I need to use in winter.
When ready to go for a winter outing I keep the isolation valves closed keeping RVAF in the small pipe portions that lead to the exterior components. I then fill the water tank via the standard cap fill and use the pump to dewinterize as normal.
Those little pipe spaces that are filled with RVAF helps keep the cold from transmitting into where the water is. I also bring the whole outdoor shower head and hose to the inside during winter even though it was flushed with RVAF and then opened up to drain any fluid out. I stuff some insulation of sorts in the space where that outdoor shower head would normally be stored.