This Dometic Climate Control Heater battery drain issue just surfaced on my friends first boon-docking camping trip. He woke up to a dead battery and we couldn't figure out why. I told him the same thing happened to me on my first dry outing and I found I had turned on the Climate Control Heater switch not knowing what it was.
This heater is otherwise known as the "heater cable" on the factory schematics and is there to help prevent moisture build up around the doors. His new unit does not have a switch to turn it off but all the factory schematics still show a switch.
I noted on another site that you can disconnect the Climate Control Heater "heater cable" electrical supply wire inside the fridges interior light so that the interior light will still function but the "heater cable" will no longer drain the battery. They both just happen to be on the same electrical feed wire from the controller.
Not sure why they would eliminate the switch but I know from experience that door heater, as I call it, will drain a single battery overnight.
We will be performing this easy modification to his to prevent this parasitic current draw:
New Dometic refrigerator problem - Page 2 - iRV2 Forums