Do you use the Coleman PC as your overland fridge? Why?
I've used the Coleman 12v thermoelectric coolers--now called Power Chill--in the past for long distance travel, though only bought one new. It was $99 bucks at a truck stop. Others were given to me by family who got tired of them not cooling things enough. I'd keep them around for parts when the fan would go out or I needed it for ice at cook-outs.
They are not really fridges, and will only cool things to 40º below ambient. So, if you're counting on using it in the summer, when you need a cooler most and it's 85º out, the cooler will struggle to keep things at 45º. If you're in the desert and the temps are in the mid 90's or higher, the cooler will struggle to stay at 55º.
If you do get one, you'll be better off putting it in a place it won't see any sun or heat, and in a place you can insulate it a bit, like with styrofoam sheet insulation, and open it as little as possible, especially if you use it in the upright position. It will keep more cool air in if you use it in the chest position.
As Don says above, they typically are not very long-lived. The little fans in the top are famous for getting clogged with lint and dog hair and all sorts of debris and quitting all together.
These coolers also draw 4 amps and run pretty constantly, where a good ARB or Engel or Dometic, etc, that are actually real fridges, only draw around 1.2 amps intermittently after they get down to temp. That means you'll be drawing down your battery faster, whether start battery or house battery.
Doesn't take long using a Coleman Power Chill to realize you want something that cools better and is more efficient in power consumption. They do much better in a house--where the temp is a consistent 65-70 degrees--than they do in a vehicle where the temp is often likely going to be hotter than it is outside.
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