Jbrowning,
We love camping in the winter time and here are a few things that work for us.
Water supply line. We bought one of those pipe heaters that you can tape to a water supply line and then put the foam tubing around that. Wrapped tape around that eveyr so often to keep everything together. Leave extra at one end so it can be wrapped or placed along the parks supply line that comes up out of the ground. Also make sure it will be able to reach the electrical supply also. Seems like that pipe is the first to freeze. If warms up during the day, which in the South East it usually does, I will disconnect the water supply heater and reconnect int he evening.
Place a tarp over the water supply also. May help you trap some ground heat.
Water holding tanks. Gray, Black, Fresh. Remember all you need to do is keep it cool. Do not need to keep it warm just keep it above freezing. We have camped many times where the temps were in the twenty and teens and have not experienced any problems with the tanks freezing. We do not fill the fresh water tank and we add RV antifreeze to the the black and gray water tanks. I would say a gallon per weekend trip. Do not know if that is helping or the amount of water and what heat from the trailer prevents it from freezing.
We use an electrical ceramic heater at night set to about sixty. Really cold it basically runs all night as its reading the temp close to the floor. Turn the furnace on in the morning so the "bears" come out of the sleeping bags.
Water heater should take care of itself as long as you leave it on.
If running a heater and plan on keeping it in the sixties in the trailer then I think the tanks and pump inside the trailer should be fine. Allow air circulation around tank if you are concerned.
Those are my thoughts and enjoy camping when most people will be at home.
Jake
