If you start out above freezing you should be ok. We camped through several winters with a 07 Jayflight. The only times we ever had issues were on Friday nights when the daytime highs didn't get above freezing. After 24 hrs we never had a problem. We also did not use the propane furnace, just 2 electric heaters. 1 heater was one a 15 amp cord run around the slideout to the pedestal, the other ran on low up in the bedroom. We also ran a fan clipped to the shower, with the cord run across the top and over to the outlet above the sink. Our 285RLS Jayflight was the same floor plan as your 281RLS. If you run the propane furnace at least some, you should not have any problems. When we did freeze up I took the access cover for the slideout motor loose and stuck a hair dryer in on low. After about 30 min the water would start to flow. It’s the line from the pump located under the window to the area under the sink that would freeze.