Refrigeration Conversion

[Mysun]

I’m looking to convert my icebox on a recent vintage 34-foot boat to a refrigerator. I have already improved the insulation around the icebox. I currently have a heat exchanger unit installed (by previous owner) but it’s not up to the job. Does anyone out there in cyberspace have any cheap alternative i.e. possibly retrofitting a domestic refrigeration unit to fit my needs. The off the shelf units are in the $700-800 price range and I need that money for beer to put in the fridge.

Ian

[boatbum]

Put your question to www.kollmann-marine.com the most knowledgable site on refigeration.

[capttb]

The Spring 2004 issue of boatworks had an article about using an inexpensive refrigerator to fit in an icebox.
http://www.sailmag.com/boatworks/boatworkstoc/

[sailnaway]

If I remember the story a guy put the cooling part of the refrigerator on the keel or on both sides of it. the lines ran back into the boat and to a standard refrigeration compressor and then into his ice box he said it worked great and was cheep. I would be a little nervous about anything through my hull but if you used mill spec copper with a thick wall I guess it would last a long time as long as the electrolisis did not get it.

[gregpecaut]

I drive truck and many add refidg to these. Many have tried marine, and RV units, but the ones that have the most sucess use an apartment fridg (from walmart) and an inverter. Cheap and it works! Adding insulation would make it even better.

[Faster]

Any refrigeration specialist can add a cold plate to your icebox, plus the necessary compressor etc, but I doubt you'll get it done for less than the $700-800 that you mentioned as too expensive.Other than getting lucky at a marine recycle store, anything you cobble together may not be reliable in the end. Don't forget to check what your "cheap" alternative will cost you in power (electrical) consumption.

[gforcepdx]

i agree with faster on this but what about the wallmart fridge and the inverter ??? curious... too janky ???

[camaraderie]

Jones...sometimes I just decide to keep my mouth shut when I know people don't want to hear the answer...especially when it is a matter of beer money!

[Faster]

Originally Posted by gforcepdx

i agree with faster on this but what about the wallmart fridge and the inverter ??? curious... too janky ???

Gforce:

The only experience I've had with the plug-in coolers is I've seen them run down a car battery overnight - So I'm assuming the power usage is too high.

These units usually use a "Peltier effect" cooler system, which is power hungry compared to conventional compressor based coolers (for equivalent cooling).

On top of that are losses factored in by the use of the inverter as well.

[sailingdog]

The "Pelletier" effect coolers are useless in really hot weather, as they can only cool a certain amount from the ambient temperature. They are also hugely inefficient. Using a "walmart" refrigerator and inverter is probably not a great idea, as the refrigerator is probably not insulated well enough for use on a boat—most small refrigerators make the assumption that they'll be used in a controlled climate area, and a boat is generally not one. A truck, like the one that Gregpecaut, can afford to run the A/C, which is often not the case on a sailboat, if it even has A/C at all.

Also, you have the inefficiency of converting the DC to AC using the inverter...if you don't think they're inefficient, just touch one that's been running a while and see how hot it is... that heat is electricity that has been converted.

Best small refrigerators for use on a sailboat are probably the Engel "Swing compressor" units. I've used one and they're very efficient. Most are top-loading designs, which helps keep the cold air inside the box when you have to open it.