HD and Lowes carry 110 volt heat tapes, but, many of them come with a warning about using them on plastic / PVC / ABS type piping.
Here's a link to UltraHeat's website. They make tank, pipe, and elow heaters that are specifically made for what you plan to do. Some are combination 110AC/12VDC.
Depending on how cold the weather gets, even pipe heaters may not be enough. Carry some disposable hand warmers (
link) in case that happens. You can wrap the warmers around pipes and valve for an emergency thaw.
Other tips for cold weather use:
Depending on how cold, you may want to do one or possibly all.
1. Leave cabinet / closet doors open to allow warm air to circulate around your plumbing.
2. If you have an outside shower (first thing to freeze), disconnect and cap the lines going to it. Standard 1/2 inch pipe thread fittings will fit most of them.
3. Don't leave fresh water hose connected. Fill your fresh tank and work from that. Store your hose where it won't freeze.
4. In the cabinets / closets, move things away from touching the exterior walls. With a lot of condensation, clothing / bedding items could freeze to the wall, or, get mildew and moldy.
5. Maybe run a small dehumidifier.
6. Open a roof vent or window, just a crack, to get dry air in from outside.
7. Run a fan to keep air circulating.
