oyarsa wrote:
The refrigerator is a Dometic DM2652 that I had set in the Auto position. Maybe I should have had it set completely on gas...
I can tell you right off the bat where you're wasting precious battery reserve ... your Dometic DM2652, the same fridge I have, has a climate control heating element that runs on 12 vdc, power it obviously draws from the battery when dry camping. A few years ago Dometic in their infinite wisdom decided to delete the switch that would allow you to turn off that heating element. :S The solution is to add your own switch, or at least cut the wire that feeds this heating element. Open the fridge door and you'll see 2 red wires running to the fridge interior light - the heavier of these 2 wires feeds the heating element so if you cut it or add a switch to it you can then disable it and prevent this unnecessary draw on your battery reserve.
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All that aside, your fridge even in the gas mode still needs 12 vdc to operate and does represent a draw on the batteries.
oyarsa wrote:
We had the water heater purely on propane.
You have a DSI water heater so even though it's running on propane it still needs 12 vdc to operate. No offense, but it sounds to me like you need to spend a bit of time with your owners manual and perhaps here on the forum so you better understand how all the various systems in the trailer are designed to work and what requires power, whether 12 vdc or 120 vac. Limit the draw down on your batteries to just what is absolutely needed and there's no reason your dual Group 24 battery setup shouldn't get you through several days of dry camping. :)