You say "house power" so ASSuming you are not living in the RV, then you can do what we do in our milder climate, which is just drain the lines, FW tank, and HW tank, after a sani-dump. Do put some pink stuff into each trap and the grey and black tanks (NOT in the HW tank).
Then when you want to go RVing, screw in the low point drain plugs, fill up with water and head on out.
BEWARE- we used to have a water filter under the kitchen sink that did not drain. It did burst when frozen and that showed up when we got a thaw. Since then we have eliminated that filter from the system.
Another goody is the outside shower to drain that, and the inside shower has to be removed from the tap set to drain right.