Battery Drain

" Checked voltage.  Both showed near 14 volt." 

Problem number one. Those batteries were not at rest. Any test placed upon batteries that haven't rested I (and I do mean I) don't trust as real. At rest they would never show that high a voltage. That's not a good read. We have not eliminated the batteries as of yet.

Please try the test I've suggested and let's hear the results. I betting a beer right now, after a 24hr rest those batteries will read about 12.3v.. Since we're talking plural, test each separately please. 

Makes sense.  I'll eventually do that. Then proceed from there.  If batteries are bad, I'll owe you a beer!   

This is good! 

" Checked voltage.  Both showed near 14 volt." 

Problem number one. Those batteries were not at rest. Any test placed upon batteries that haven't rested I (and I do mean I) don't trust as real. At rest they would never show that high a voltage. That's not a good read. We have not eliminated the batteries as of yet.

Please try the test I've suggested and let's hear the results. I betting a beer right now, after a 24hr rest those batteries will read about 12.3v.. Since we're talking plural, test each separately please. 

+1 to Offgrid's reply. We had new dual 6V batteries. The first night of our first trip with it, we had it on battery after driving for a few hours, so the batteries should have had a good charge. This was with a Ford Escape with tow package and I had run a good power circuit as one was not there originally. The batteries did not last all night and we woke up to a beeping refrigerator in the wee hours. We did not have shore power available, so I tried propane, but it would not light. It was when I pulled the outside cover off with a friend looking that I found that the flame was shooting out toward the orifice instead of up the flue. We interrupted our trip and backtracked a couple of hours to get to the dealer who found a wasp nest. The dealer tired to say that it happened during the week between us picking it up and the start of our trip. I doubted it very much since we bought it in December after we had been though a couple of freezes. The dealer wound up clearing out the wasp nest and ordering new wiring for igniter because the insulation on the wires was burnt. Regardless, we ended up having to use the propane on that trip and it wasn't until after we returned that the wiring was replaced.

I have been very leery of running the refrigerator on DC since. I only now feel confident that I can do so since I put in a DC to DC charger for the LiFePO4 battery I installed in place of the dual 6V batteries and ran a dedicated power circuit for it from our Frontier using a battery isolator solenoid to ensure that enough amperage would be delivered to both charge the battery and have enough surplus to power the refrigerator while underway. Still, unless I have shore power, when we are stopped I will be using propane for the refrigerator.