How to Convert a Mini Fridge to a Chest Refrigerator

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Introduction: How to Convert a Mini Fridge to a Chest Refrigerator

About: Engineer making renewable energy products for African entrepreneurs.

It's just awful that when I open my refrigerator, all the cold air falls out. This makes me sad. So, I turned my refrigerators word upside down, or at least 90 degrees. Now, when I open the door, more cold air stays inside and this makes me happy - it increases my quality of life in fact.


For the rest of you with a large refrigerator.... I, and my partner in crime have something cooking for you. But, it's going to take a month or so as I want data showing this big refrigerator modification works. As you read meters are whizzing and collecting :)

Step 1: Aquire Fridge

This particular model was discovered in the annals of the UCF dumpsters during dorm move-out. The funny thing is, it was found, in the dumpster, with ice inside.

Step 2: Unscrew Compresser Assembly

To speed up production time, the compressor is assembled on a compressor mount separately from the rest of the unit. So, unscrew the compressor assembly from the fridge.

Step 3: Rotate Compressor

Firmly grasp the compressor and rotate it 90 degrees so that the top of the compressor faces what will become the bottom of the refrigerator. Try not to move it too much to prevent damage to the lines coming in and out the compressor.

Please note, it will take a fair amount of force to rotate the compressor assembly. This is normal.

Step 4: Support

If your refrigerator is designed like mine, the compressor assembly will not fit back into the space provided by the fridge manufacturer. I scrounged up 4 1/2 inch PVC couplings to act as spacers. I'm also using a spare bit of 1/2" PVC pipe and two 90 degree elbows to make feet.

I used 5 minute epoxy ($1 from harbor freight) to secure the feet and coupling risers.

Step 5: Turn Fridge Upright - Ignition

And by upright I mean on it's back - the new bottom :)

Before turning on, you'll probably want to let the compressor sit upright for a few hours, to make sure any oil settles back at the base. I'm not quite sure this is completely necessary as I believe the lubrication is in the refrigerant itself, but perhaps its best to play on the side of caution.

Now, plug your chest refrigerator in and turn it on :)

Step 6: Freezer Modification and Stock Up

For those wanting to turn a refrigerator into a freezer, it shouldn't be too hard. The only thing you'll need is a new thermostat that is connected to your compressor. As mine will be used, for now, as the beer fridge with spirits locker - I will not be converting to a freezer.

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    79 Discussions

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    TJJ16

    1 year ago

    The whole point of this instructable is to show you how to rotate the compressor so its new upright position is in line with the refrigerator being on its back. You have to read the rest of the steps. I think it's a great idea. Can't wait to try it on my mini-fridge.

    any issue with condensation
    dont refrigerators use some kind of gravity drain that drains into a condensation pan below the fridge?

    1 reply

    You've got the right idea. Most refridgerators have a condensing motor/pump that needs to be right side up. But if this works, more power to them. If it fails, that's probably why.

    I am iranian.

    Hello.please send you file pdf for me .if you can.thanks.
    Email :nader etemadzadeh@yahoo.com

    Works great !!! Converted yesterday an today my beer is coooooold

    I know this is old, but I thought I should point out, no fridge uses suspended lubricant, they are all oil bath (any suspended lubricant would significantly reduce efficiency). That being said, the oil isn't that thick, and there's no need to leave it overnight, a couple hours will do nicely.
    Also the reason for letting it sit is not so it doesn't run out of oil, but because if the lines get full of oil (as it's so much thicker then the gas) it could clog the expansion valve, and that could damage the compressor.

    The small compressor on a fridge hold abought half a litter of (usually mineral) oil.

    1 reply

    Bit of a mistake.
    r12 and r22 systems use mineral oil, r12 was banned in 1995, but r22 is still used (supposed to be phased out by 2020), but most companies favor r134a and it uses peg oil.

    Great Idea. thanks for the instructions. I want to apply this to my large family fridge. How did you go with your large fridge data and conversion. I could not find it on the site.

    Have you posted anything further in relation to that?

    thanks for your great contribution.

    Thanks for the instructions. I build mine last night, and decided to take someone's advice by building a wood frame for it to sit on. I didn't have any shelves in it before, so I increased my capacity from about 14 to now over 50. Needless to say, I'm excited for the Super Bowl.

    chest.jpg
    1 reply

    I decided that I needed some storage system for a warm beer "on deck" rack. This is what I came up with:

    By the way. Where is the heat exchanger on your fridge? Mine is on the back and I'm wondering if it is possible to do my fridge this way.

    1 reply

    Potentially?

    Here's what I've learned.... You need a  measuring device - like a Kill-a-Watt or similar.

    1. Monitor power consumption during normal use - upright. Do this for at least a week to get smoother and potentially more reliable data (longer is better)
    2. Reset the measurement and repeat for the same amount of time, but this time empty the fridge and throw in a 1 or 2 gallon jugs of water (to make up for missing volume) and DO NOT open the door.

    Compare the consumption for these two tests.

    At the end of the day, for this mini fridge - there was no difference :( It always consumed a LOT of power (nearly 1.5KwHrs/day - the same as our main apartment big fridge!)

    My reasoning as to why this is the case? Thermal mass. Air doesn't have much mass compared to the rest of the cold objects and as a result doesn't carry much of the "coolness." For example, if there's .25 pounds of air* in the fridge, and 75 pounds of food and cold refrigerator mass, the air in that fridge makes up 0.5% of the chilled mass.... And that doesn't even take into consideration actual thermal mass (which is material dependent).

    ------
    To answer your other question
    Th condenser is in the skin ;) Should you ever take one apart - and I don't recommend it :p You'll find copper tubing behind the outside metal skin... Super inefficient - but extremely cost effective from an mfr perspective :p

    ------
    At the end of the day, these small refrigerators aren't very energy efficient (your measurements may vary) :p

    I've got one of these fridges But it has a heat exchanger on the back.

    Can this still be done with what I got ?

    letting it settle is definately a good idea.  the compressor itself sits in an oil bath as seen here http://www.youtube.com/watch?v=MxWoNjvLZWY&feature=related and that oil is what has to settle.

    2 replies

    Thanks :)

    As it turns out, it really doesn't matter in this modification - just as long as the compressor is upright during operation....

    Why?

    Looking at the orientation of the evaporator (and condenser) - gravity isn't going to allow anything to get back into the casing...

    Oil shouldn't be able to get out of the HP side... and most compressors have a muffler connected to the suction inlet - so I'm not worried :) Even if some does escape via the suction side, it's going to get pulled through fairly quickly :)

    This is mind, I didn't wait to fire up this refrigerator - and the compressor worked quite well until I stopped using it due to it being superfluous :)

    Hi we bought a thermostat of ebay to convert a chest freezer  into a refrigerator and it works fantastic, the motor hardly ever runs and it stays icy cold, we live off solar power so we needed a large chest  fridge that would hardly use any electricity as we use it for storing  milk and fresh produce.    
    it only took 5 minutes to change the thermostat over and we didnt have to modify anything just swapped the thermostat as it looked the same as the thermostat we pulled out , we looked at other ways to do a freezer into a fridge conversion and  this was by far the easiest way  
    we bought it off    freezer2fridge  in Australia
    http://cgi.ebay.com.au/Turn-a-Freezer-into-a-Fridge-Thermostat-Kegerator-Solar_W0QQitemZ160372777342QQcmdZViewItemQQptZAU_Home_Appliances?hash=item2556f6617e

    Hey, this is a great project. Thanks for posting it.. Does anyone know if a similar technique could be used to turn an upright freezer into a chest freezer? Also, is there any news about turning a standard sized fridge into a chest fridge? Thanks, if anyone is still listening.. Suz.