Move Refrigerator Compressor?

[gabriel]

I would be interested in the physics rationale for "leave it on all the time". In my delivery days, I was always amazed at the horrid places the boat designers put compressors--in a closed box, near the engine heat, etc. Always amazed that they worked at all. I have a 40 year old Adler Barbour unit that works great (I have upgraded the fan on the compressor and put a small one in the bottom of my box to circulate) that is located in the lazarette away from the engine. In my years In the tropics I used to open the lazarette at night to ease its burden, but it provided frozen food and beer all these years--main problem was too cold. I had to turn it off periodically before I located a very small computer fan in the bottom of my box-wired to the compressor--because the unit would freeze stuff there. Solved that problem. Keep wondering if "keep it on" is just so that your compressor can recover some cool at night when it is cooler or if something else is going on.

doesn’t matter where the evaporator is located. Temperature doesn’t make a difference to the cycle as all you need is a temp difference to extract latent energy from the freon and condense it into not even liquid but semi liquid. The work of cooling is done by the compressor, not the ambient air temperature.

also, do we ever turn off our home fridge?

 

[Pete the Cat]

doesn’t matter where the evaporator is located. Temperature doesn’t make a difference to the cycle as all you need is a temp difference to extract latent energy from the freon and condense it into not even liquid but semi liquid. The work of cooling is done by the compressor, not the ambient air temperature.

also, do we ever turn off our home fridge?

OK maybe my physics is off, but a refrigerator is basically a heat pump. It takes heat out of your box and dissipates it somewhere. So it seems to me if the "somewhere" it is trying to unload the heat is already at 120 degrees it is going to have to work longer to unload the heat. Am I missing something?

 

[Loren Beach]

Judging by comments about reefer installs over the years here, I believe that most owners know that the little fan cooled compressor unit needs cool or at least ambient temperature air over its fins. The difficulty is that so many of these were/are installed in compartments with little air circulation. On a hot day the machine struggles to transfer heat when it is immersed in hot air.

I did the install for our initial foray into this luxury by installed a "keel cooler" thruhull fitting and it worked well, and over time, we decided that boat in out temperate climate really did not need that much technology. When that system died after a decade, I started over with a new 'conventional' fan cooled radiator on the compressor chassis. This seems to run as little as the prior more efficient system. Of course the whole system might be more efficient with every iteration.

The model designation seems to evolve over time but this is pretty much what ours looks like. https://www.suremarineservice.com/Galley/Air-Cooled/ISO-42503BA100000.html
I have our air-cooled unit mounted under the galley counter module with air flow from both sides. I would guess that any boat with this unit more tightly enclosed.... needs to provide passive or forced ventilation for it. Maybe even a muffin fan and a vent grill.
I should note that we can feel the slight warmth of the air exhaust thru the vent, but it is not very warm at all. This is not noticeably adding to interior warmth on a hot day, but then we are at about 45.5 N Lat, and do not get the intense heat down in California.

I should note that refrigeration is the ONE amenity I have added that totally changed our life on board!

 

[bsangs]

Mine runs continuously from April to October, at about 32 degrees. Like Christian’s, it runs off the battery bank, which is charged by AC at the dock and solar/alternator when cruising. When too much frost or ice accumulates on the plate, I’ll change the setting to 50 degrees for a day or two to defrost it. I did recharge it earlier this year, which was a simple process, and improved its efficiency. Also swapped out a noisy condenser fan for a mostly quiet new one. The accumulation of dust and general wear made the old fan squeal like a distressed squirrel.