The Cold machine is most common. SuperCold machine uses water cooling
. It's fine as long as the water
isn't saltwater. They seem to have problems in salt water
more often. One hint of salt water
in the system and it's pretty much trashed.
The basic Cold machine with the evaporator or cold plate can be purchased for about $1000. You could DIY. Building the box takes a little skill since you want lots of insulation
and an inside that is easy to clean. Be nice to line it well and add a drain so you could use Ice if needed. A shorter passage
could then use ice and save the power.
The average lifespan seems to be 16 to 20 years. There is almost nothing you can do to service
them so they tend to live long. It's nice if you can set up a space for the air cooled compressor
. The last two I've had were in lazerettes and both lasted the expected time. I just happened to buy the boats at about the end of life. They tend to work well until the day they don't. They don't seem to go down bleeding your money
as they go.
thickness that matters maybe the most. Add a good tight sealing lid and it's a lot of fridge space compared to the drop in boxes.