Refrigerator mode while travelling - Event Date: 11 Jun 2014

DC will put a good dent in your battery after 6-8 hours of use and drain a group 24 battery in about 10 hours.  Of course, if your charge line is properly wired, fused and gauged, your vehicle's alternator will supply the required power while you're travelling.  My advice would be to switch over to propane while stopped more than an hour for lunch.

DC mode is adequate for maintaining a cold fridge.  It really is nowhere as quick as propane in its ability to cool down a fridge (or its contents).  I've never noticed any inconsistency in temperature on DC mode - hot days, cold days, whatever, it runs just fine.

Safety.  *sigh*  There is always an argument here.  Some people are dead set against running propane while the trailer is in motion.  On the other hand, many RVers travel with propane running (and on larger RVs, there usually isn't a DC option available).  Its certainly legal to run propane appliances while travelling (except in some tunnels, the rare bridge, or on ferries), although propane MUST be shut off while filling your tow vehicle with gasoline.

In case of an accident where a propane line is cut, there is a safety valve in modern propane tanks which will automatically shut off gas flow.  This safety, however, will not cut off because of a slow leak or nick in a propane line.  Its an excellent, proven safety system, but there are still rare incidents where the safety doesn't work.  But, for some, running with propane on while there are other, safer options is not worth the risk.

Personally I almost always use the LPG on the road.  One less thing to fiddle with on boondocking trips - set it before leaving the driveway and forget it until you get home.  It uses very little propane, a full tank, if not used for heat or cooking, will last a full month.  Many worry about keeping it lit at gas stations, but gasoline is heavy so it stays close to the ground, and also has a very narrow flammability range.

DC mode has a few caveats which is why I use LPG.  First you must have a good sized wire, I recommend 10 gauge, between the battery under the hood and the Bargeman connector (the 7-in connection next to the hitch).  The cheaper wires installed by places like Uhaul are just too small, usually 12 gauge.  If the fridge is on DC mode it uses 11 amps, then if your pod's battery is low it will suck up all amps it can get to recharge.  You'll end up with a large voltage drop and ultimately a warm fridge and still-discharged battery since it isn't seeing 13+ volts.  Next you must have a good ground wire from the Bargeman either to a good bolt close by, or you need a heavy gauge wire back to the battery.  Another catch is the fridge can deplete a fully charged battery in a few hours, and a depleted battery much quicker.  So if you stop for lunch you need to switch to propane.  You shouldn't turn it off since the ammonia absorption system used by camper fridges take a lot longer to "catch up" than your home's fridge.

Bigger fridges in motor homes don't even have a DC mode, they use LPG all the time on the road.

Edit:  took me a while to finish my post, I see others have responded with much of the same info.

Charlie, it draws 11 amps while actively cooling.  The refrigerator cycles on and off during operation;typically its on about 15-20% of the time.  Of course, it'll cycle more frequently with hotter outside temperatures (or if the fridge isn't precooled, obviously).

Ferry rides - 30 min to 4 hours. Plus time waiting in que. You can't say, opps we are starting to load and make the switchover, when it's time to move its time to move!

Battery draw is not continuous, only when it kicks in to a cooling cycle. If it's been running and cold, it shouldn't cycle that frequently. Plus part of the time your TV will be running while loading.