Hi SCOUT, welcome to the forum.
As Dave said, a search will bring up some good detailed info about winterizing. Often the forum search link at the top of the page doesn't narrow the search enough. Here is a link to a Google search of the forum that may work better. https://cse.google.com/cse/home?cx=0...95:95x3m3w6lto
Here are a few of the easier answers to some questions.
when my camper is hooked up to my well via a water hose, does the water go into the fresh water holding tank?
- When you hook up to the "city water" connection it feeds the internal plumbing directly. You should add a pressure regulator to keep the "city water" pressure under 40 lbs. The water pump has (or should have) a built in check valve that does not let water go into the freshwater tank. There is also a check valve just inside that city water connection that does not let water out that connection when you use the fresh water tank and pump.
how do I drain all the water from the system
- There should be "low point drains" somewhere in the camper near the floor that you can open to drain MOST
of the water from the water lines when you open the faucets. If you look under the camper you should see 2 pex pipes (usually red, hot and blue, cold) that stick down from the floor. The valves will be inside just above those pipes. The fresh water tank has a seperate valve somewhere, depending on the particular model Sunline.
how do I sanitize the system?
- Use 1/4 cup of 5% household bleach to 15 gallons of water in the freshwater tank and pump it through the plumbing. Let it stand for at least 3 hours.
These answers just barely touch on your questions but hopefull are a start.
Remember, we never consider any question on this forum to be a "dumb question" since we were all new to this at one time. Feel free to ask anything here.
Also, if you know the model number of your Sunline, someone here may know the exact locations of the low point drains and the freshwater drain.