3-way refrigerator

Originally posted by CharlieM The short answer is no. The Dometic is rated at 132 Watts (12V x 11A) on DC and 144 watts (120V x 1.2A) on AC. More watts means more cooling so DC is slightly less effective than AC. Propane is usually about equal to or somewhat better than AC. That's by the numbers, but experience has shown the DC operation is noticeably worse than on AC or propane. Not sure why, but I think some earlier Dometics were rated a bit lower on DC. That said, the fridge will really suck the battery and, depending on how well the TV is wired, may actually discharge the trailer battery while towing. At best you will only trickle charge the TT battery since most of the current is going to the fridge. Due to the design of the flow limiting safety valves on modern propane tanks there is little danger of operating the fridge on gas while towing. Larger fridges in RVs do not even have a 12V option. It's either propane or shore power and nobody thinks a thing about it.

I'm picking up a new 2014 181-G from our local dealer this Saturday and had a question about the efficiency of the 3-way refrigerator in 12V mode.  Or previous TT (27' Salem) worked great on propane, but I always felt a little nervous driving down the highway that way.  Does it cool as well on 12V as it does on 115V or propane?