# what's the word on marine fridges these days?



## sallysailor (Jun 21, 2010)

I've been out cruising for a while. My Glacier Bay fridge draws 34 amps and i am tired of running the generator every time i need to cool the icebox...anyone have any suggestions on the best, most efficient coldplate/compressor technology?


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## eryka (Mar 16, 2006)

We are huge fans of Frigoboat. We have had the keel-cooled version for about 6 years now. It is virtually silent and the compressor takes very little space. We have 2 LARGE fridge boxes, one of which includes a small freezer. We insulated them heavily including 2 layers of reflectix. We draw a total of only about 30 amp-hours per day in 70-degree water. Their website gives good tables & formulas to estimate your usage.

They're not cheap, we paid about $1500 (?) with a boat show discount back then. But we were able to do the install ourselves, and its been very reliable since. Wait for opinions from some others, we've heard there were some problems with Frigoboat a few years ago, don't know if its been resolved yet.


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## sailingdog (Mar 19, 2006)

I'm a big fan of the Engel portable refrigerators. Most of them are dual voltage and will switch from 12 VDC to 110 VAC automatically if connected properly.


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## CaptainForce (Jan 1, 2006)

My 12VDC Technautics refrige/freezer draws less than 1/10th of the amps you describe. I think any of the manufacturers that use the Danfloss compressor with the small fan for air heat exchange would be the most efficient. Take care and joy, Aythya crew


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## TQA (Apr 4, 2009)

I have an Adler Barbour Super Cold Machine and am well impressed with it. It makes 2 trays of ice cubes a day, keeps a large top opening fridge cold, all for about 40 amp hours a day.

I do not even use the water cooling option. Current Location the Windward Isles.


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## Bene505 (Jul 31, 2008)

sallysailor said:


> I've been out cruising for a while. My Glacier Bay fridge draws *34 amps *and i am tired of running the generator every time i need to cool the icebox...anyone have any suggestions on the best, most efficient coldplate/compressor technology?


Do you mean 34 amp hours a day, or is it really burning 34*12.5=425 watts? If the latter, any idea how much it's cycling on? 425 watts seems ok if it only runs for an hour or two each day. That much is supportable by a 170+ watt solar panel.

Regards,
Brad


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## skipgundlach (Oct 4, 2002)

sallysailor said:


> I've been out cruising for a while. My Glacier Bay fridge draws 34 amps and i am tired of running the generator every time i need to cool the icebox...anyone have any suggestions on the best, most efficient coldplate/compressor technology?


Two things:

I agree about frigoboat and the keel cooler. Our box was built new from the outside in with reflective barrier first (aluminum foil epoxied to the frame), air barrier (doorskin battens to the AL foil) and then 6" of extruded polystyrene which had been epoxy coated first, with laddered joints in bottom, top and corners to make air path even more convoluted in case any epoxy missed a joint space, epoxied as it went in. Very efficient...

Second, do you have cold plates, or do you REALLY pull 34A when an evap system is running?

The keel cooler (and the similarly acting one which can go in the sink drain) doesn't require a water pump or to run a fan for cooling, increasing the efficiency/cutting the AH costs significantly.

Frigoboat has a smart speed sensor which makes the Danfoss idle when it's not under a lot of new-heat load, but kicks it up to full when needed. Therefore, the compressor runs about 90% of the time, but the total AH is better than running full blast for a while and then off most of the time...

L8R

Skip


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## olson34 (Oct 13, 2000)

*another vote for FrigoBoat*

I did my own install of the Frigoboat system with keel cooler.
When it runs, and that's not too often, it draws about 3.8 amps. We have a well insulated box from the factory, and I have added some more external insulation.
One thermostat died, and the replacement was around $30. It keeps the box at about 37 to 38 degrees. If I turn the control above about "5" it can drop the temp to 20 easily.
We have two GC house batteries and can easily run the boat at anchor in the summer for two full days and still have ample power to start the diesel without invoking the spare "starting / emergency" battery.
I have install pics over at a longish refrig. thread on the EY.org site. Let me know if you want the URL.

L


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## wind_magic (Jun 6, 2006)

The newest insulation for refrigerators are the aerogels.

R value 10+, "frozen smoke", the next best thing to a complete vacuum.










Source: Aerogel (Wikipedia)

But they are too expensive!

No, not anymore, you can buy the stuff in rolls now, they are even putting it into clothing.


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## RichH (Jul 10, 2000)

I prefer SeaFrost, easy for DIY installation and use the Danfoss 12 vdc compressors. Service, tech. advice, etc. is outstanding.

The 'quality' of the box/freezer insulation is the 'key'.


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## sallysailor (Jun 21, 2010)

*thanks for the info!*

this gives me lots of good stuff to consider...thanks so much to all who replied!


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## asmilingshark (May 9, 2008)

*New Fridge Project*

I have just installed my new SeaFrost, the BD version. Makes ice in a few hours and is as quiet as quiet can be. 8.5 c.f. are devided by a partition and the one with the evaporating plate has basically become a freezer. I run the unit on the lowest setting. It was my DIY and the support from Cleave was great. He put up with tons of questions and was very patient in answering them as well as offering to customize a couple of parts if need be. A great service and a great little machine!


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## hellosailor (Apr 11, 2006)

Water cooled beats air cooled the same way that electric light beats oil lamps.

I never liked the idea of a keel cooler because it is "more stuff" located where you can't possibly access it to fix it. But I saw that fridgoboat isn't really a kell cooler, all they use is a "plate" bolted into the side of the hull, much like a DynaPlate. Very small, simple, damned robust. I think if they'd stop referring to it as "keel cooling" they'd sell a thousand more.


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## deniseO30 (Nov 27, 2006)

The transfer of heat to water is way more efficient Even the warmest waters are still cooler then air where some condensers are located; cept maybe near geo active islands LOL


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## CaptainForce (Jan 1, 2006)

hellosailor said:


> Water cooled beats air cooled the same way that electric light beats oil lamps...............


Very true, but (and it's a very big but) you have to spend a great amount of energy to pump water past the coils and it requires very little energy to blow air across the coils. I can freeze 2.5 cubic feet and refrigerate an added 6 cubic feet with 3 amps using a Danfloss compressor and a small fan. I don't think that the current water heat exchange systems can move enough water efficiently to do the same job for the same amperage. Tell me otherwise, if it's done. Take care and joy, Aythya crew


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## tdw (Oct 2, 2006)

CaptainForce said:


> Very true, but (and it's a very big but) you have to spend a great amount of energy to pump water past the coils and it requires very little energy to blow air across the coils. I can freeze 2.5 cubic feet and refrigerate an added 6 cubic feet with 3 amps using a Danfloss compressor and a small fan. I don't think that the current water heat exchange systems can move enough water efficiently to do the same job for the same amperage. Tell me otherwise, if it's done. Take care and joy, Aythya crew


Capt, our fridge is water cooled. I'll take some readings over the weekend although remember it is mid winter down here. I'd guess a summer reading would be more meaningful.


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## deniseO30 (Nov 27, 2006)

Keel coolers don't use water pumps. just the refrigerant flows through the lines and the seawater just absorbs the heat even if the boat is not moving.


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## fallard (Nov 30, 2009)

We installed an Isotherm system with the heat exchanger in a thru-hull (that also handles the galley sink drain). It is "self-pumping" and uses an "automatic startup" process that speeds up the danfoss compressor when a charging voltage is sensed. 

I was curious about the energy usage and left the refrigeration on at the dock for a number of days with the shore power disconnected. The fully charged batteries ( 3 ea. 27 series gels) ran down to about 12 volts after about 4 days. My icebox is very well-insulated, so that helped, as well as not adding anything or even opening the box during that time except to observe the holding plate (frost) every once-in-a-while.

The first year we used a special zinc (~$36 in the current Defender catalog), but didn't see any appreciable depletion. We took it off and haven't had a problem in the 7 or 8 years since.

Bottom line: the Isotherm unit with thru-hull cooling has worked like a charm and appears to be very energy efficient. That said, your energy consumption will probably be determined by the insulation of your box and how you use it. Best to avoid buying warm beer!


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## MacGyverRI (Nov 14, 2007)

If you don't need a lot of room (I mostly use the "Ice box") I use a Goldstar 1.8 Cu. Ft. Dorm fridge for necessities like butter, milk etc.. It only uses 85 watts and it's run via a Black and Decker 100 watt 12 volt Cig. lighter type converter. I don't use the big 1000/2000 watt converter since it uses more juice than the little one or the Fridge...

The 2.8+? Cu. Ft. (Norcold boat fridge size) larger dorm type fridge doesn't use a lot of juice either.

Another few options


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