How To Make A Mini Fridge – 13 Steps, 13 Hours, Get It Done At Home!

When preparing for a summer camp with your buddies, you get to pack yourself with all the pieces of equipment. But what about a freezer? Won’t it be great if you could get a portable fridge along? Yep! It’s possible if you know how to make a mini fridge yourself. 

In this article, I’ll share how I built my fridge from scratch without spending a big buck. For this DIY job, I bought most parts you see in a typical refrigerator. 

And the best part is it’s portable, though you’ll need electricity support through batteries. So, it runs on low electricity. Read along to learn more about DIY refrigerator making at home. 

Note: Since it’s an electrical project, follow each step without skipping to avoid mistakes or incidents. 

How Does A Refrigerator Work?

You need to understand how a freezer works prior to learning how to make a mini fridge. Before refrigeration was invented, people used to salt their food to keep them chilled. 

In those cold regions, people also used to bury the foods under the snow to avoid contamination. 

Thanks to modern technological evolution, now it has become so much easier to keep our daily intakes fresh for a while with a refrigerator. The process of refrigeration is actually based on a simple principle. 

“When water evaporates, this absorbs heat. On the flip side, if water condenses, it releases heat.”

For example, on a summer day, a frosty cold drink bottle will have water condensing outside, which warms the drink. 

A freezer uses 5 components To pull off this frosty spec.

1. Refrigerant
2. Expansion device
3. Evaporator coils
4. Condenser coils 
5. Compressor 

First, the refrigerant liquid enters into the following expansion device. When it passes through the device, a sudden pressure drop is created. Then it expands, cools, and turns into a gas.

When the refrigerant circulates around the mentioned evaporator coils, it starts absorbing the heat from the inside of the food. 

At this stage, the compressor squeezes the refrigerant and, as a result, raises fridge temperature and pressure. Then it’ll flow through the condenser coil (once that you see on the back of the refrigerator.) The refrigerant radiates the heat into the atmosphere and turns it back into a cold liquid. 

It’ll then again enter the expansion device to repeat the cycle from the beginning, in brief. The heat is consistently picked up from the fridge inside and taken outside the machine. 

How To Build A Mini Refrigerator That Uses Almost No Energy?

In order to make your portable mini freezer, you need the below tools. You can get most of them online. I’m adding the online links for your convenience. 

Requirements:

Components
1K Resistor	LED & Holder
Acrylic Sheets	Perforated Board
Arduino Nano	Relay Module
Door Handle	Rocker Switch
DC Jack	Spray Paint
Foam Boards	Super Glue
Glue Sticks	Rubber feet
Hinges	Thermoelectric Cooler Module

Tools

Jigsaw

Dremel Rotary Tool

Glue Gun

Dremel Workstation

Soldering Iron

At A Glance

Thermoelectric Cooler: 

This module will ensure uninterrupted heat flow, which helps keep one side hot and another cold (as mentioned above) by maintaining consistent heat transportation. 

There are 2 arrays in this module, -p and -n semiconductor parts. You’ll see both are fixed with some electrical carriers. 

When buying this module, don’t buy a Peltier module unless you got SMPs or CPU. Get a whole unit that comes with every essential piece. 

Get more ideas about how the Thermoelectric cooler module works in this video.

Arduino Nano: 

It’ll let you know the temperature inside the fridge with the help of the DS18B20 sensor. Whenever the temperature goes below 3-degree°, it’ll turn off the current power supply to the refrigerator. 

On the contrary, if it reaches 7-degree°, the power supply will be restored or switched back to on. The refrigerator can keep up with the adequate temperature in this way. 

That was the necessary brief about the parts and terms. Let’s directly dive into how to make a mini fridge now. 

Step 1: Cut Acrylic Sheets

To give your mini-fridge a shape, start cutting the sheets you bought. Before that, confirm the measurements you need. 

I built this specifically to store cold drinks and beers. Therefore, mine was a bit small (7.6 x 12 x 11 inches). You need to cut the sheet into 6 rectangular pieces. Use a jigsaw to cut the sheet into the required pieces. 

Measurements Example:

• Top: 12 x 7.6 inches 
• Floor: 12 x 7.6 inches
• Right and Left Panels: 12 x 11 inches each
• Front and Back Panels: 7.6 x 11 inches each 

Note: To make it stronger, you can add a double sheet on both front and rear panels. You’ll also need some additional sheet pieces to make compartments or shelves. 

Step 2: Cut Slots For The Peltier Module

You’ll need to set the thermoelectric module on the front and rear side sheet at this stage. Get a measurement of the plastic radiator (follow the image for reference). Create the same outline on the sheet. 

Use a drill or impact wrench to make a hole through the lines. Now adjust your saw in the hole and cut through the outlines. 

Step 3: Do Some Painting Jobs

Now it’s time for the artistic part of the job. The acrylic sheets you bought are supposed to be wrapped with paper. Remove those. Spray the paints on those sheets (panels and compartments) and give them some time to dry. 

Cautious: Use a mask while spraying. Paints on the acrylic surface tend to take more time to dry. To dry the color faster, spray in an open place.

Step 4: Built A Path For Ventilation 

Two separate cooling fans come with the fridge unit. These will help to evaporate the heat from the hot side. You need to set them in the enclosure so there won’t be any issue with the airflow. 

Again, measure the fan and outline it on the newly painted sheet. If you’ve bought the one I suggested, it’s supposed to be square in shape. Then, create a hole with your drill and cut through the lines. 

“Typical 8mm drill bits aren’t convenient for making the hole. A Dremel work station provides an easier experience.”

Step 5: Set Up The Cooler Unit 

Add some glues on the sheet you just cut through for. Then carefully position the Cooler radiator. Once it’s positioned correctly, apply some more glue around the radiator to make an air-tight sealing. 

“Making the radiator is essential. Otherwise, the hot air will enter inside the side panels.”

Now, you’ve to split the base section into two compartments: one side is for the cooler, and the other is for your supplies. Basically, you’re separating the fridge into two parts. 

You need to measure the complete fridge. So, take a scale or any meter tape and find out the length of the device. Like before, create an outline with a pen or pencil. 

Since the sheet with the cooler unit is quite slightly heavy, you should glue it firmly on the base or platform sheet. Instead of the previous one, use the hot glue for the purpose. 

However, it might not be sturdy enough yet. Add something on the back so that it can support the sheet and keep the position at 90-degree. In the picture, what you’re seeing is my old battery 😉.

Set the other sheets (left and right) and stick them with the glue. 

Step 6: Make A Support For The Cooling Unit 

If you lift the whole unit, you’ll witness it already become quite hefty as you’ve connected fans and heatsink together. So, it’s necessary to add some support to the unit. 

You can use foam to get this done. Measure the underneath space left of the cooling unit and cut the foam accordingly. Insert the foam board strips in the space and glue them for a better foundation.

Step 7: Create The Rear Panel 

Until now, it was mainly the crafting part. Now, you’ve to go through the major phase or the engineering part. 

Begin with the back panel. Create some slots as you see on the image for LED, DC input jack, and the switch. Then set the piece of equipment with glue.

Note: Some may prefer using an LED holder instead to set the light. It’s up to you.

To create the circuit diagrams in the right way, solder wires following the below instructions: 

• 2 wires to the DC jack (Red wire = Positive, Black wires = Negative)
• 1k resistor with positive wires (+)
• Red wire to another part of the resistor 
• Black wires to the negative (-) end of the LED
• For the Peltier module, pick wires, one red, one black

Step 8: Build Fridge Cabinet Or, Sliding Tray

It’s totally up to you how you’re gonna store your stuff inside the freezer. For example, one for chocolate, another one for drinks. Whatever you want to store, divide the freezer’s inside accordingly. 

Use the leftover acrylic sheets to create some small strips. You can add two or multiple pieces together to make them thicker. 

“I would advise to do so as these will hold the weight of the divider shelf. And those will hold the weight of your cans or other things you’ll store. “

Fix these to the side panels with glue. While gluing them, keep space between the strips as per the tray size. It’s also important to keep the same height of the strips from the platform or the base panel. 

Cut another sheet to make the tray. Finally, when the glue is stuck perfectly, insert it there. 

Step 9: Partitions For The Circuit

You can make a partition to divide the hot side part into two sections. It’s like separating the heat sink and fan part into one section and leaving another section for the circuit. So, add another piece of sheet with glue there. 

Step 10: Make Insulation For Fridge Interior 

Insulation can significantly increase the coldness inside the refrigerator. That’s why you see ice boxes have those foams inside. You’ve to do so to ensure maximum efficiency. 

First, get the measurement of interior sheet walls to start with the part. Then cut the sheet or board for insulation you’ve bought accordingly. This time also uses hot glue to add these to the wall. Make sure there is no way left for airflow. 

“While insulating, you can either add foam on the front panel or leave that blank. Leaving it will make the front side transparent. It may look cool, but insulating this part also is a more effective approach.”

Step 11: Add Front Door 

If you’ve taken all the measurements correctly, hopefully, there won’t be any issue matching the front door at this stage. And if, for any reason, it doesn’t match, get the front side of the unit measurement, and resize the sheet cut earlier for the door. 

After the mapping is done, add a handlebar to the sheet. You can do it by either drilling or gluing. Then mount a henge on the sheet with screws or glue. 

Make a few more foam strips to set on the border line of the door sheet. It’ll give the door proper sealing. 

Step 12: Measure And Control The Temperature

Now, you’ve to place the circuits, including the Arduino, inside the hot side compartment. You can use a tiny bread board to make a connection. Follow the below orders: 

• Solder 3-male headers
• Use electrical tape in order to insulate both ends
• Apply some glues to the top cover

You can find the Arduino code in the attachment below. 

Download Arduino Code

Step 13: Make Feet For The Miniature Refrigerator

You need to create 4 feet for the unit with rubber. I used a piece of plastic to make them. Note that it’s mandatory because acrylic sheets slip on the flat surface like countertop boards. You can either glue or screw feet.

Some prefer adding a piece of cardboard on the exterior to give it a natural look. You can try it if you want. 

Final Step 14: Let’s Test!

Well, you’re almost done. In this final step, you’ve to connect the unit with a power supply with the power connector. It should be a minimum of 12 volts (10A). 

After connecting the freezer as shown in the image, turn it on. If you’ve cracked the game without any mistake, the LED should light up, and at the same time, the fan will start working. 

I suggest keeping this on for 20 minutes at least to stabilize the inside temperature. Afterward, you can store your drinks inside for cooling.

How To Paint Your Refrigerator To Give It A 1000 Dollar Look?

Everyone wants to keep their stuff unique. And when it comes to home appliances, we just become more desperate. Your fridge is one of those appliances that show off your personality. Then why live with a dumped fridge if you can give it a sophisticated makeover?

Yes, you can do that in multiple ways. If you’ve good artwork skills, then use this skill on your cooling machine. Even if you’ve never painted before, it’s easy to decorate your fridge under 60 minutes with a new color! You can also wrap your fridge with stunning adhesive paper.

Frequently Asked Questions

What’s A Kegerator?

A kegerator is a fridge that has been modified to function as a beer dispenser. They are popular in bars and restaurants and can be used to serve cold beers or mixed drinks. Kegerators come in different sizes and styles and can cost anywhere from $700 to $1,000+.

Why Do You Need One?

Kegging is a great way to have your own quality beer on-hand without having to go through the hassle of cleaning, filling, and storing a separate keg for each batch. It also allows you to control your beer’s carbonation level and sweetness, which can be useful if you’re trying to make something unique or experimental.

Can I Add Tap Through The Door Of A Mini Refrigerator?

Yep, it’s possible to turn your mini fridge into a kegerator with a tap. But you’ve to do a lot of work as the kegerator has a different gravitational force working inside. There is a detailed guide I wrote on how to turn your mini fridge into a kegerator here. 

How To Refrigerate Without Electricity?

You can use a refrigerator that operates on solar power to cut the cost of your utility bills. You can also use a USB mini fridge; this consumes less electricity. 

Another advantage of a USB mini fridge is that it’s portable. An icebox is also a known solution to keep your foods cold without electricity for a short period. 

What Features To Consider When Buying A Compact Fridge?

In the case of a mini or compact refrigerator, the most important thing to consider is the size, both inside and outside. Identify whether it’ll fit in your space or not. Before buying one, set your mind about what you’re going to store inside. Find out if it does have enough space or shelves to fit your needs accordingly. 

Other features to look for in a compact fridge include a small footprint, adjustable shelves, a bottom freezer, and a water and ice dispenser.

What’s The Average Weight Of A Dorm Fridge?

You can find dorm fridges that weigh between 150-400 lbs. On average, they weigh around 250 lbs. 

Can I Put Towels Under A Mini Refrigerator?

If your freezer leaks water, place a towel underneath the machine. Make sure to turn the power off before. Also, check if there is melted ice or water inside the fridge.  

Does Mini Fridge Weigh Heavy?

Well, mini ones don’t weigh too much compared to the basic fridge. Even the most common mini – fridges weigh 60 lbs. max. 

Can A Mini Refrigerator Explode?

Any fridge on earth that operates on a compressor can explode if not maintained properly. The key reason that causes mini – fridges to blast is when the heated gas returns to contact with the compressor and gets trapped there. To avoid those issues, read your fridge instructions after buying. 

Another reason that causes fridges to explode is the excessive frost issue. Thus, you should frequently defrost your mini-fridge. 

Wrapping Up 

That was all about how to make a mini fridge without having an engineering degree. Thanks to the online market for making those components accessible to anyone. 

I would advise you to double-check each step before moving to the next, especially the circuit board part. Any wrong touch can cause severe accidents. 

I’m eagerly waiting to know how you’ve made your own DIY fridge. Ping me in the comment section with your experience. Cheers!

You can also check out the following articles: 

• Guide & Tips 
• Decorate Your Mini Fridge In 60 Minutes!
• Build A Mini Fridge Cabinet Using Basic Tools
• Learn How Big Is A Mini Fridge