DISCLAIMER: This is just my experience with wintering in a 2-3 season travel trailer and does not constitute expert advice in any way. Please do your own research and know your risks.
“I left South Carolina on a bleak and drizzly Monday . . .” (December 31, 2018) with temperatures in the 30-50s. I had bought this 2-3 season camper earlier in the month of December and had lived in it (with my dog, Hiker), parked in the driveway, since that time.
For power, we were simply plugged into a 20amp exterior outlet off the garage and used an electric space heater for heat along with Reflectix covers behind all the blinds. The water systems in the rig remained winterized from the dealer. I used a bucket toilet (or restrooms at gym, store, etc.) and a jug. For water inside the rig (drinking and washing), I used Reliance 7 gallon water containers. A plastic sink liner bowl could be set in the sink for gray water could easily be thrown out when full.
After leaving, we traveled across the county, hitting the first ice and snow in Texas and spent an icy night at Guadalupe Mountains National Park on the Texas-New Mexico border. I used my backpacking zero-degree sleeping bag as a comforter and usually slept in my clothes. I also used the Olympian Wave 6 Catalytic Heater which provides wonderful ambient heat without an open flame or requiring an electric fan.
The catalytic heater does not off-gas or produce high levels of carbon monoxide (mounted right next to the propane and CO alarm which never went off), and is highly propane-efficient (versus the rig’s furnace, which would also have run down the battery by using electric for the fan). The only issue with propane heaters is humidity and condensation (especially around freezing temps - i.e. trying to bring the temp up from 30-40s).
We eventually settled in for a few weeks in Quartzsite, AZ where temps were routinely 50-60s during the day and 30-40s at night. I started using the rig’s bathroom and black tank while in this location, using the gray water from the sink bowl to flush the toilet. I still used a jug for most liquids as this kept the black tank use to a minimum (emptied once in 3 months on the road). I also used RV-safe antifreeze in the black tank prior to use - my thought being that it seemed unlikely that the entire tank would freeze but that the drain pipe needed to be protected (by putting antifreeze in first, it went to the lowest point - the drain - and protected that area). When a gym shower wasn’t available, I used body wipes for a “Navy shower.”
My first travel nursing contract was in North Dakota and our route took us through Santa Fe (New Mexico) with more snow, then Colorado for a ton more snow (this was the first and only time emptying the black tank on the road which I thought best as we were back in routinely freezing temps - there was some ice slush when emptying but nothing solid or obstructing - the antifreeze had done it’s job). I did not use the black tank again after this until warmer summer temps in North Dakota.
We drove through a blizzard going up through South Dakota and finally settled in Bismarck (North Dakota), with several feet of snow and temps regularly as low as -10-15. Other than two overnights in Arizona and South Dakota, this was our first campground in three months (dry camping on BLM or other public land prior to this). Once again plugged into to power, I was able to use the space heater again which on high was able to keep temps in the trailer around 50-60s even in the coldest of outside temps. I used the camp shower and bathroom until warmer spring and summer temps made it safe to use the black tank again - once this happened, I also finally dewinterized and started using the water systems.
We spent summer in Colorado, finishing up that contract just as first the snows started. I used temperature monitors placed inside, in the outer compartments, and under the rig to monitor temps around the external water systems (radiant heat from the rig was enough to keep the pipes from freezing but towards the end, I was also routinely leaving the water dripping as well to keep the water moving - I found the hose and faucet at the pedestal would freeze long before the rig’s plumbing). Once we were back in truly freezing temps, I simply disconnected the water and used the low point drains to empty the system and went back to using water containers. I did not winterize other than to continue to place antifreeze in the black tank with each use. When we arrived on the North Coast of California for the next contract (very temperate, 40s at lowest), the water system worked again flawlessly.
Hope this helps to share some ideas but again, just one person’s experiences - not expert advice. Safe travels!
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