CPAP = Continuous Positive Airway Pressure - Helps breathing at night.
We decided against 6v batteries, as we had one fail. You can't just cut one out of the circuit as you can when a 12v battery fails.
We gave up on trying to add a second house batter, as it was very expensive, and labor intensive.
Now I'm looking into a portable solar system that you just unfold and set up next to the RV, and plug in.
2016 Redhawk 26XD
Me, Dear Wife,
2 Bluetick Hounds
1 Newfoundland / Black Lab Mix
1 Cairn Terrier