I stopped using anti-freeze back in 2008 when I had still had my ROO. I usually also camped over Thanksgiving, NYE and in February so true winterizing was not practical. Since I bought the MH I am out during winter months. Once again, no anti-freeze used. I drain the lines as best I can and have not blown them out in four years. I do use low temp switched heaters in the basement and living area and to date have never had an issue to include the outside shower faucet. I guess one could suggest that is living dangerously but so far so good. And yes, I can hear Dirty Harry in the background!
