It would seem to me that it would be best (more efficient) to always run your refrigerator on DC. Any disadvantage? Some units come with DC only. (Truck Fridge or Isotherm)
To ensure mine only runs on 12v, I unplugged the AC.
Mike
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Alaska to Key West, Labrador and more
Prostate cancer survivor. See Thread Prostate cancer and Sportsmobiles
2015 VW GTI 2020 Fiat 124 Spider
2012 E250 Hitop camper
This is likely only the case if it is a 12V or two way (12V/120V) fridge. However, if it is a three way (12V/120V/propane) it will not run very efficiently on 12V and will use a lot of battery capacity while doing it.
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Josh
2009 Express AWD, CCV Top & 50-ish home build. Daily driver/camper/kid hauler
its possible if its got the danfoss compressor. I had the edgestar fp430 and used a wattmeter to measure its use during a 24 hour period. It uses about 25 amps total in a 24 our period when set to 40 degrees. The lower you set it the higher the amp usage.
i had it in the back of my van and eventually got rid of it because it would put out too much heat when running. but even when the temperature in my van was in the 90's the inside of the fridge was in the 40's as set.
as long as you got a large enough battery and means to replenish it, you can run all the time. My ran 24/7 just on a 75 ah agm battery and 120 watt solar panel but on cloudy days it couldnt keep up with fridge.