How to Make a Refrigerator

Homemade Refrigerator

Making your own refrigerator sounds like a complicated endeavor. It can be a fairly simple process with a little advance planning. It can also be good for the environment. Building a DC powered refrigerator using a junk refrigerator for parts will not only be energy efficient, but it will also keep junk out of the landfill. Many people consider learning how to make a refrigerator the ultimate DIY (do it yourself) project. If this sounds like a project you would like to tackle, follow this quick guide to help get you pointed in the right direction.

Things You'll Need

• Junk refrigerator
• Basic tool set
• Permanent marker
• Circular saw
• 2x4 Studs
• Foam insulation sheets
• Spray adhesive
• Compressor
• Thermostat
• Evaporator
• Car battery
• Electric drill
• Plywood sheets
• Liquid nails

Instructions

Prepare the Food Storage Box

1. Locate a non-working refrigerator that can be used to salvage basic parts. Junk shops, used appliance stores and recycling centers are great places to find beat up old refrigerators. Try to find one at a recycling center if at all possible, because these places will have already removed the refrigerant gases for reuse. It is ok if the second hand refrigerator is beat up or does not work. Check the inside food storage area to make sure the plastic is in good condition and not busted, as this is the main item you will be using.

2. Strip the refrigerator down. Start by removing the doors so that you will have easy access to everything. Remove any motors, compressors, thermostats, evaporators or other components to this refrigerator. You have no way of knowing how old these parts are or if they work, and it is best to make your refrigerator using new parts. You may wish, however, to salvage the door light from the refrigerator. Locate the wire that leads to the light switch and keep it separate from other parts so that you do not remove it by accident.

3. Take the freezer unit off of the old refrigerator. Using a chest freezer is cheaper and more energy efficient than having a freezer mounted to the top of your refrigerator. It is much easier to make a refrigerator if you do not worry about the freezer, so you will want to cut the freezer compartment off of the box. Use a permanent marker to draw a line all the way around the unit, just above where the main storage compartment ends. Use a circular saw to cut along this line until you completely chop the freezer off of the unit.

4. Construct a platform that will raise your refrigerator off the ground. Having removed the freezer and other components from the refrigerator, you are left with a basic storage box. Because this box will appear short, it is helpful to make a platform to elevate it off the floor. This has an additional benefit of giving you extra storage space under the refrigerator. Use 2x4" boards to build a basic square platform frame that fits the dimensions of the bottom of the refrigerator. Build the platform 12 to 18 inches tall, to suit your personal tastes, and lay two sheets of foam insulation on top of it to help prevent cool air from escaping the bottom of your refrigerator.

5. Insulate all sides of the storage box using sheets of foam insulation. Measure each side of the storage box and use a hand saw to cut the sheets of foam insulation to fit. Spray both the surface of the box and the surface of the insulation with a spray adhesive, then firmly press the insulation into position on the refrigerator. Do this to all sides of the storage box, including the top and the door. A well-insulated refrigerator will be more energy efficient. When finished, spray adhesive on the insulation that is on the platform you constructed in the previous step and place your storage box on top of it. The storage box has now been prepared and is ready for you to make a refrigerator.

Install the Refrigeration Components

1. Buy the parts that will be needed to build a DC powered refrigeration unit. Check with various marine supply stores for refrigeration kits. Most carry these parts because refrigeration units on boats are powered by direct current. The majority of these kits include the use of the Danfoss BD-50 compressor, which has become the standard compressor for anyone who wants to make a DC refrigerator. An ideal parts kit is the "Super Cold Machine" kit. This package and many other parts kits can be purchased from "R Parts Refrigeration Parts Solution" or another marine supplier. These kits typically include a compressor, evaporator, thermostat and all hoses that are required to connect the components.

2. Install the compressor. The compressor includes a condensing unit and should be installed in a well-ventilated area. Most manufacturers recommend that you install the compressor away from the refrigerator, since it will produce heat. In an ideal situation you will have a basement and can install the compressor in the rafters of the basement, under the floor space of the refrigerator. If this is not possible, your refrigerator will likely be situated next to cabinets, and the compressor can be placed in an empty area of your bottom cabinets. There is nothing to hook up at this stage, you simply need to find a stable place to sit the compressor and condensing unit.

3. Install the evaporator inside the refrigerator. The evaporator disperses the cold air that the condensing unit supplies, and also evaporates any cold water that is formed by condensation. Start by using an electric drill to drill a 1.5 inch hole in the area where the evaporator will be installed. Drill the hole all the way through the storage box. Push the refrigerant tube through the hole from the outside of the refrigerator into the inside. Slide the tube over the connecting port on the evaporator inside the storage box, and tighten into place with a screw clamp. Once the hose is connected, use the screws provided to mount the evaporator to the back wall of the storage box.

4. Connect the thermostat to the evaporator. The thermostat allows you to control how cold the temperature inside the storage box will be. Use the screws provided to mount the thermostat, which is usually attached directly to the storage box. Take the wiring from the thermostat and push the plug into the slot on the evaporator.

5. Connect the condensing unit to the evaporator. Return to the hose that you pushed into the refrigerator to connect to the evaporator. Grab the other end of the hose and lead it to the condensing unit on the compressor. Push the end of the hose onto the receiving port of the condenser and tighten into place using a screw clamp (included). The condensing unit now has a method of distributing air to the evaporator.

Finish the Refrigerator

1. Fill the condenser with refrigerant. In order to supply cold air, the condensing unit will need to using a refrigerant gas to cool the air. Freon is the most common refrigerant used in refrigerators and air conditioners alike, and can be purchased from any air conditioning supply company or hardware store. If you do not want to spend extra money for the brand name, ask for CFC-113 instead. This is the generic name for Freon.

2. Make a veneer finish to go on the outside of the outside of the refrigerator. This will make your refrigerator appear more attractive. The easiest way to make the veneer is to use ¼ inch sheets of oak plywood, cut to fit all sides of the refrigerator's surface. The wood can either be stained or maintain a natural finish, depending on your taste. Use a construction adhesive, such as liquid nails, to apply the wood to the sheets of foam insulation. You should also put the door back on the refrigerator at this point.

3. Connect the power supply. The kit that you purchased with your compressor, evaporator and other components should also include a fuse power supply. The compressor, evaporator and door light should all be plugged into this power supply. The power supply is then connected to a 12 volt or 24 vote power source, which is a standard car batter (for 12 volt) or two car batteries (for 24 volt). Your refrigerator will be fully operational when the power supply is connected.

Tips & Warnings

• Since your batteries are not connected to a running motor to recharge them they will need to be manually charged with an automotive battery charger from time to time. You can avoid the hassle of this step by building a solar panel to continuously recharge your batteries. Refer to the Resources section for information on building a solar panel.

Resources

• Read this Article in Portuguese
• R Parts Refrigeration Parts Solutions
• Danfoss Refrigeration Supplies
• Build a 60-Watt Solar Panel
• Build Your Own Solar Panel for Cheap