Mini Fridge Soda Fountain

Here is how the system works: A small air pump is connected to an AC power switch that is plugged into a nearby outlet. When the switch is activated, the pump begins to push air through a tube and into a soda bottle. As the pressure inside the bottle builds up, soda is forced out through a second tube. This tube takes the soda and pours it out into your glass. To keep the soda cold, you can put it inside a small refrigerator and run the air tubes through the wall of the refrigerator. This setup gives you a really basic soda fountain.

The easiest way to route the hoses into and out of the soda bottle is through the cap. Find a drill bit that is the same size as (or slightly smaller than) the tubing. Then drill two holes in the center of the cap.

Try fitting the tubing through the holes. You want it to make a tight fit so that air doesn’t leak out.

The best way to keep your drink cold is to leave it in the refrigerator. To accommodate this, we need to run the two air tubes through the side of the refrigerator. There are several ways that you can do this.

The simplest method is to just run the tubes through the door. However, this creates a large gap around the tubes that will let the cold air out of your refrigerator. The refrigerator will still work, but it will be much less efficient.

Another option is to cut a slit in the gasket around the door. Just take a knife and carefully cut a hole in the gasket, behind the magnetic strip, that is just big enough for tubes. This will still leave a gap, but it will be much smaller.

The last option is to drill holes for the tubes in the side of the refrigerator. This method requires a little planning. You want to be absolutely certain that you do not drill anywhere near an electrical wire or a refrigerator coil. First you want to locate where the electrical wires are run inside the refrigerator. Follow the power cord to see where it enters the housing. Inside the refrigerator it may go to the light, the thermostat, or a fan. The wires will typically take the shortest possible path. Then you need to locate the refrigeration coils. The easiest way to do this is to open up your refrigerator and feel which parts of the walls are the coldest. If you are having a hard time sensing a temperature difference, then you may need to let the inside of the fridge warm up to room temperature first. The back wall is the most common place to find the coils. Once you are 100 percent certain that you know where the wires and coils are, you can drill two holes somewhere else in the housing for the tubes. If you are not sure, then use one of the other two methods.

Now you need to connect the hoses. First feed both tubes through the holes in the soda bottle cap. One hose should reach all the way to the bottom of the soda bottle. This is the output hose. The other hose should go through the cap but should stay above the level of the soda. This is the intake hose.

Next, feed the hoses through the side of the refrigerator. Outside the refrigerator, the intake hose should be connected to your air pump. The output hose should be routed to the place where you want to be able to refill your drink.

Plug the AC power switch into a nearby outlet. Then plug the air pump into the power switch. Lastly, take the output hose and set it up where you want the soda to be dispensed. The distance from the refrigerator doesn’t matter. However, the strength of the pump will limit how high you can pump the liquid. Mounting the end of the output hose can be as simple as attaching the hose to a nearby wall or table. Or you could make an elaborate 3D printed nozzle with sensors and flashing lights; the choice is up to you.

Now all you have to do is press one button to refill your drink. You can even set up the system with a long output hose that will dispense drinks on the opposite side of the room from the refrigerator. Try it out, and have fun.