I have good success using the blow out method but here in Northern Neck Virginia where the winters are not all that hard...
We camp alot in the late part of the season and run into alot of freezing temps over night that warm up durng the day. The blow out method is perfect for this.
My compressor is one of those 12VDC tankless type which is slower to build up pressure. I hook up to the city water inlet using an air adapter. I open all the spigots including the high pressure hot water heater valve and drain all of my low points. It all works fine for me to blow out my simple water system and then I add some pink stuff to the trap.
This is pretty much all I have to deal with on my somewhat small foot print trailer setup.
With this method I can revert back to using the water system the next day by just adding water to the fresh water tank.
If I had a bigger trailer I would probably do it alittle differently... Everyone has their own problems to deal with I guess...
Been running around the cold high country of VA, WVA, NC, TN, and North GA since 2008 doing it this way with no problems so far...
Roy Ken
