Originally Posted by jimdic
If you plan to use anti-freeze, you will need to pick up a fitting that attaches to the intake on the water pump. Be sure to use the valves to isolate the water heater so no antifreeze is going into the heater. Besides filling the waterlines, you will need to put about a quart of anti-freeze in each of the drains. If your camper has the cassette toilet, make sure you drain the flush water and add anti-freeze to that as well.
If you're looking for a permanent solution, see about picking up a antifreeze fill kit, like this one from Camping World
That way you only have to disconnect the plumping once. From then on in subsequent years it's just the turn of a valve.