It really depends on your water and storage. We always start a trip with full water tank for several reasons:
- a full water tank reduces tongue weight
- a full water tank makes the torsion axle work better
- from October to May most Colorado public campgrounds shut off all or all but one spigot - and that may be at the dump facility. Counting on water at the campground leads to rude/disastrous surprises. Same applies to Wyoming. Last summer due to Covid, many Forest Service campgrounds never got their water tested/approved, and so had none.
When I lived outside Colorado Springs and had well water, I had to drain the tank after every trip. If I didn't, first the water heater and then the tank would get that sulfur smell after a few weeks of the camper sitting. When we moved to the city, the water stays good for a year or more.
During the summer, I just top off the water tank at start of each trip. In late fall, I drain the water tank after a trip, and refill at start of next trip. When I fill, I go through 2 fill steps to get the water heater filled (it takes 6 gal of your 20 gal tank to fill if you wait until arrival at the campsite). The attached garage where I store the A-frame stays just warm enough in winter to not freeze the plumbing so I don't winterize.
I found that releasing the pump water pressure before starting to tow prevented pressure build up problems from the sun while towing. I would have pressure locks preventing the pump from turning on and/or leaking from the jostling of the fold-down sink faucet. After turning the pump off, I simply open the valves on the outside shower and bleed water pressure off. Then shut the valves.
hope this helps
Fred W
2019 Flagstaff T21TBHW A-frame
2008 Hyundai Entourage minivan
camping Colorado and adjacent states one weekend at a time