There is sticky somewhere about dewintersizing but I can't find it. LOL
The short version is:
Put about 10 gallons of water in your fresh water tank. Put a cup of bleach int here then.
Turn your pump on and run all the water through all the outlets. shower, kitchen sink, toilet etc..
Once it is is empty, do it again, but without the bleach.
Then open the valves to fill your hot water tank. Fill it, then drain it, then fill it again and you should be good to go for the summer.
2015 32 Foot Rockwood 8289WS 5th Wheel
2013 Chevy 3/4 Ton TV