Keeping refrigarator cold while driving - Event Date: 26 Jul 2014

I live in Colorado and our dealer mentioned that altitude plays a part. For those running on 12V, where are you using yours?

After having learned how absorption and compressor refrigeration both work, I've discovered a new technology for refrigeration that involves the use of magnets!

See this video for a brief overview: https://www.youtube.com/watch?v=WlKKKMTA7XM

Apparently, certain metal alloys get hotter or colder when brought into contact with magnets. Once they get colder, for instance, you can pass a liquid over or through them which is then carried to what you want to cool.

Right now, this requires a fair amount of space but could probably be fitted into a house sized refrigerator. But they're working on reducing it down to a pump about the size of a car alternator. At that point, it sounds like it would be a very viable new way of cooling things without a lot of space.

However, it would require electricity to move the magnets, so I'm not sure if it would ever be as good in a RV situation as propane. The amount of energy in your propane tank is many times greater than what is in your batteries. A single deep-cycle marine battery has about the equivalent electrical power as five CUPS of liquid propane. A 20 pound propane tank has a little more potential power than 25 typical marine batteries.

Originally posted by GingerPod Good info Charlie, If the TV is set up from the factory,I/E "tow package" like on full size domestic trucks,it is possible to travel down the road with the fridge on DC. with no ill effects. Of course propane is so much more efficient.But nice to have that option should you run out of propane on the way home from your camping adventure,especially  during a cold snap when propane use could be higher than planned. Now I can't speak for all Models,but my Silverado with the "tow package", has a 12 ga. wire, a dedicated stud pickup with a 40amp fuse  and a 120amp alternator feeding the Bargmans connector.It seems GM was thinking ahead on this one.More power than the Fridge could ever use if needed.

The answer to the first question is yes if the truck is really wired correctly. This can be checked with a meter comparing the TT battery voltage with and without the truck engine running.

If the truck uses a #12 wire with a 40A fuse you have an excellent candidate for a recall, and a fire. A #12 wire should be protected by a 20A fuse. That wire will melt and catch fire before the 40A fuse ever thinks about blowing. That said, the #12 will drop so much voltage over the 15'-20' to the Bargman that you'll get very little charge. I think many US manufactures use #10 on the charge line and even that's too small. With a 40A fuse the wire should be #8; six would be even better for charging.

I added a second battery, and it works great. Keeps refrigerator cold al day while running, then recharges when I am plugged in at night

Increasing the size/gauge wiring between the truck battery and the Bargeman is the single best thing you can do to improve the cooling ability of the DC mode of the fridge.  My 2010 Chevy has 12 gauge wiring and the fridge temp starts to rise after just 2-3 hours on the road due to voltage drop.  For instance, with ONLY the load of the fridge (11 amps) run over 20 feet with 12 gauge wire, that is a full volt drop from the battery to the back bumper.  That means some of the load will be carried by the camper battery.  Add in a low battery on the camper and the voltage drop will mean you get nothing from the truck and the battery on the camper will be discharged quickly.