Has anyone converted a small AC 110 volt fridge into a DC 12 volt fridge?

[magentawave]

I found a company that will convert any AC fridge or fridge/freezer you bring to them into a DC/12 volt fridge by swapping out the existing compressor for a different one. They charge $1000 if you buy one of their little off-the-shelf fridges or will deduct what you spent on the fridge you bring them to convert from the $1000. In other words, if the fridge or fridge/freezer you bring cost you $250, then they will charge you $1000 - $250 = $750.

The guy that does these conversions said its not very difficult to do the conversion yourself if you didn't need to first invest several thousand in some kind of machine that can suck out the freon and then put it back. So I was wondering if anyone here has done the work themselves to convert their own AC fridge or fridge/freezer into DC? Are their businesses out there that can suck up the freon and then put it back after the compressor has been swapped out? Just hoping to find a way to do this for less money.

 

[Haf-E]

Interesting - who is the company and where are they? Shipping would be the hassle...

I have a fridge that was converted from AC to DC years ago - works well. Now uses a 12/24 vdc Danfoss compressor. I think any good commercial refrigeration guy could do it - pretty similar to swapping compressors on a supermarket display case frig. Basically is who did mine.

 

[magentawave]

Here is the guys websites that does the AC to DC conversions: http://www.offthegridrefrigeration.com/Home_Page.html and http://www.cruiserowaterandpower.com/EcoFridge.html

 

[teotwaki]

A chest style fridge/freezer will be more efficient as you do not spill out the cold air every time you open the door. You can buy them set up for both AC and DC so that you can run them off of AC "shore" power when available.

 

[quickfarms]

For a small fridge you are probably better off with one of the commercially available units. This is a good idea if you have an oddball size or antique one that you want to keep.

 

[magentawave]

I'm still figuring this out and know that chests are a lot more efficient but I'll be traveling alone and am not one to hang out with the fridge open.

A chest style fridge/freezer will be more efficient as you do not spill out the cold air every time you open the door. You can buy them set up for both AC and DC so that you can run them off of AC "shore" power when available.

Yes, if I do this then it would be a small fridge/freezer like this Vissani at Home Depot.

I was thinking of running an AC fridge with an inverter but was told that DC is 30% to 40% more efficient. I don't know these things though. What do you think?

I have a question. Are you talking about a dorm type (used in some motels also)?
If this is the case, I would think a inverter would be a lot cheaper then changing a compressor. For a $1,000.oo you could upgrade your alternator add a additional battery and inverter. Just a thought!

 

[4x4junkie]

Most dorm fridges are woefully inefficient, drawing almost as much power as a modern fullsized household fridge, which would probably knock your battery out completely in a matter of several hours, especially when combined with the losses of converting DC to AC. I wouldn't think a DC conversion would help much either (insulation is huge factor on a fridge's power consumption). ×2 what both teotwaki and quickfarms said above.

 

[quickfarms]

Most dorm fridges are woefully inefficient, drawing almost as much power as a modern fullsized household fridge, which would probably knock your battery out completely in a matter of several hours, especially when combined with the losses of converting DC to AC. I wouldn't think a DC conversion would help much either (insulation is huge factor on a fridge's power consumption). ×2 what both teotwaki and quickfarms said above.

Modern small basic refrigerators do not use that much power. There are many off grid cabins that use solar panels, batteries and an inverter to run one. The school conversion is more efficient due to the efficiency loss in the inverter.

 

[magentawave]

I just sold two of the big Edgestars because I didn't feel it had enough room in it and I read that the others are a lot more energy efficient than Edgestars. By the way, Edgestar plays fast and loose with their measurements because if you measure the Edgestar 80 quart model you will find out that its actually only about 60 quarts. I wonder if measurements for Engel, ARB, and Dometic are bogus too?

Before I would spend the money doing a conversion or the inverter. You will have power loss by running the inverter. I would buy a Edgestar Fridge/Freezer for $500.oo more or less depending on the size you buy. I have the big 80 Qt. size (it is big inside) and good for a weeks worth of food for 3 to 4 people. It is now over 5 years old and no problems. If you get one of these take the access cover off and tighten every electrical screw and spade plug. Run at least a 10 gage wire to the unit cigarette plug (8 gage would be better). The Edgestar has a low voltage cut off so you can start the vehicle if you stay put for a couple of days. It will cut off the fridge so you do not drain the battery. I have not run a second battery and never had a problem.

If you have any additional questions I will be happy to give you my opinion or experiences.

What is this "school conversion" you are referring to? Do you think the Vissani fridge at Home Depot would be 30% to 40% less efficient than DC if I ran it off of an inverter?

Modern small basic refrigerators do not use that much power. There are many off grid cabins that use solar panels, batteries and an inverter to run one. The school conversion is more efficient due to the efficiency loss in the inverter.

 

[4x4junkie]

Edgestar's efficiency is right on par with other units according to the tests I've done on mine (what some people say about these units isn't always the truth I've noticed). As for it's interior measurements, I haven't tried to calculate it's capacity, but my 43qt has way more than plenty of room for a week's worth of food for 3 people.

Modern small basic refrigerators do not use that much power. There are many off grid cabins that use solar panels, batteries and an inverter to run one. The school conversion is more efficient due to the efficiency loss in the inverter.

Looks like they are getting better (the one magnetawave picked has a rating of 235kWh/year, down from the 300+ that was common), but that's still 2/3 what a household fridge like this one uses (345kWh/year) yet has less than 1/4 the capacity, and isn't even self-defrosting. Something specifically designed from the beginning for DC efficiency (like an Edgestar, or of course an ARB too) should use much less power than what that Vissani unit would use, and avoids the DC-AC conversion loss.



Edit:
Maybe one of these units might well fit the bill?
http://www.solar-electric.com/sundanzer50l.html
http://www.solar-electric.com/sudcbare12.html

If the power consumption specs are correct on them (they sound optimistic to me, but certainly I have no experience with them), it beats my Edgestar by a mile (and the 50L is about what a unit like the ARB costs).



Edit again:
Checked my Edgestar's inside measurements... (w/o baskets)
11.375 D
18.375 W
15.750 H (that is subtracting .250 for the inside of the lid that sticks down)
_________
~3292 cu in.

Minus the shelf for compressor:
11.375 D
7.75 W
7.50 H
__________
~661

Comes to 2631 cu in. (or 45½ quarts) Dunno about the 80qt, but the 43's numbers certainly don't seem bogus to me...

 

[magentawave]

Those Sundanzers are super efficient because they have 4.33" thick insulation everywhere. I was seriously considering the Sundanzer 165 but when I finally whipped out my tape measure and went over the dimensions inside my 18' Sunrader I could see it was ridiculously big. In fact, I don't think I can even get it inside the motorhome! I considered the Sundanzer 50 too but I think 1.8 cu ft is too small for full time living. I wish they made something between the 165 and 50. Is it crazy to consider two Sundanzer 50's side by side? And what about pulling the guts out of a small used DC fridge and install it in my own custom built super insulated ice chest?

 

[4x4junkie]

Is it crazy to consider two Sundanzer 50's side by side?

Could use one as a fridge, the other a freezer


No doubt, insulation is the key to any fridge's efficiency.

I guess using guts from a DC fridge in a custom-built insulated box or chest would work, though that sounds like a pretty ambitious project (especially if you have to break open the refrigeration circuit to install your evap coil). Let us know how it works out if you do go that route.

 

[highlandercj-7]

For what they charge to convert you can have any purpose built portable out there. ARB Engle what ever.

 

[pugslyyy]

I found a company that will convert any AC fridge or fridge/freezer you bring to them into a DC/12 volt fridge by swapping out the existing compressor for a different one. They charge $1000 if you buy one of their little off-the-shelf fridges or will deduct what you spent on the fridge you bring them to convert from the $1000. In other words, if the fridge or fridge/freezer you bring cost you $250, then they will charge you $1000 - $250 = $750.

The guy that does these conversions said its not very difficult to do the conversion yourself if you didn't need to first invest several thousand in some kind of machine that can suck out the freon and then put it back. So I was wondering if anyone here has done the work themselves to convert their own AC fridge or fridge/freezer into DC? Are their businesses out there that can suck up the freon and then put it back after the compressor has been swapped out? Just hoping to find a way to do this for less money.

In addition to having the freon evacuation equipment, you also need to have some pretty good copper pipe soldering skills, electrical skills, and the ability to pump down, dry, and purge the system.

At the end of the day you would have a 12V dorm refrigerator that was never intended to be used in a dirty, dusty, high vibration environment with highly variable ambient temperature and humidity conditions.

I don't understand why you wouldn't just buy an Engel.

 

[matthewp]

For what they charge to convert you can have any purpose built portable out there. ARB Engle what ever.

Bingo! Or even a good marine fridge/freezer if you really want the "traditional fridge style" front-opening option.