When we first got our trailer, we drove for 4 hours with the frig on 12V and had a nearly dead battery when we got to our campsite. We took the trailer in for service after we got back to get the wiring checked and all was ok. We may not have adequate wiring from the tow vehicle to the trailer battery to keep the battery charged.
Since then, we always use propane on the road and it works great!
Since then, we always use propane on the road and it works great!