Gee I'm not the only one. I've been using a 3CF dorm fridge running on
inverter for 6 years now. Uses about ~50amps DC a day, more in the Hot
delta weather. But in Summer there is more
solar hours too. I'm at
anchor quite a lot, months at the time and do that sailing thing.
The basic mechanical compressor design between the 12V and 120V systems are the same. The main difference is the 12V is somewhat smaller
displacement, so runs more then The 120V units. Too much heal may burn one out, but that has not happened to me yet. Think the wave movement, rocking the
boat back and forth, lubricates the compressor well enough.
Don't forget to include the inverter losses, an extra amp for the 12V to 120V conversion. My basic magic
chef fridge runs 10 minutes an hour (2.5 on every 10 minutes) in the heat of summer (93
cabin temps in the hot cali Delta). It runs less in cooler
weather.