DIY: Air Conditioning

Summer in Luxembourg comes in short, random bursts and when it does arrive, it can be unbearably hot, especially these last few years. We aren't near the ocean so it's sticky and stuffy. My bedroom is on the top floor and is so much hotter than the rest of the house. We do have a fan and sometimes leave the windows open but that just makes the hot air circulate around the room. So my boyfriend and I decided to do a project after seeing it on various websites. DIY projects with Stefane are easy because he is a complete perfectionist which means he usually does all the work (although I do try to help where I can). I'll let him take over and explain what to do, it's really simple and affordable. 

You'll need: 

A standard cool box - 14€ 

(it doesn't have to be fancy, we chose the cheapest one)

A small fan - 9,99€ 

(again, we chose the cheapest one we could find)

A pipe, diameter of 10cm - 5€ 

(we used a curved pipe so that we can redirect it)

5-6 screws - 0,50€

Optional:

Duct tape - 5€

Aluminium plate, 1-2mm thick - 4€

Total: 38,49€

Tools:

Electric drill with a 5cm diameter drill head attachment

Screwdriver

Shears or strong scissors

Knife (optional)

Pencil

Electric screwdriver

Start by disassembling the fan with the screwdriver, so that you only have the piece with the propeller and the electric engine. Trace around this piece on one side of the lid of the cool box (not in the center), this will be the outer circle. Then draw an inner circle one centimeter from the one you just traced, so that you can attach the fan later on. 

Use the electric drill with the attachment to drill through the top of the box, in order to make it easier to cut around the inner circle. This is the most time consuming part of this project, because the lid of the cool box has several layers of hard plastic. Once you have cut through it all and neatened it with the shears and the knife, attach the fan using the screws and the electric screwdriver. 

Next, use your pipe and place it on the side of the box, opposite to the side where you put the fan. Try and place it as far away from the fan as you can, to guarantee a bigger air way and to ensure that the air is cool enough. Trace around your pipe and drill another hole, then neaten it with the knife again. You won't need to screw this part, but make sure the hole is not too big for the pipe. Stick the pipe in and if the hole is too big, then you can use the duct tape to make sure the air doesn't come out of the hole itself. The air needs to come out of the pipe to guarantee better air pressure. We didn't need to use the tape as the pipe fixed quite snug. 

And that's it. You can also use the metal plate so that there are two floors in the cool box, you simply have to shape it like a small table so that you can put frozen bottles or ice packs under and over it, to create a even longer air way. This is optional and we didn't feel the need to use it. 

We tried this using two different methods, ice packs and frozen water bottles, using old bottles and tap water. We found that the water bottles have a thinner layer of plastic, meaning they didn't insulate as much as the ice packs. This means the bottles can absorb the heat from the air quicker than the ice packs, which ensures a lower air temperature. Basically, the bottles made the air cooler than the ice packs.

Now to put our creation to the test. The outdoor temperature was 24°C/76°F that evening and when we put the air conditioning box on, the temperature sank to 13°C/55°F within two minutes. Indoors it was 25.5°C/78°F and the box temperature sank to 5°C/42°F. Even though it was hotter indoors than outdoors, the sun wasn't shining and there was no hot wind trying to get in to the box.

It's obviously not comparable to a real air conditioning unit, which cools the room to the desired temperature, because our DIY air con only cools a standard sized room down by one or two degrees. However, it does make a noticeable difference and it feels amazing to have cool, dry air instead of the same stuffy air going round and round with the fan, making sleeping more bearable. It makes as much as a standard fan. It's also a lot cheaper to buy, you don't have to install it and it doesn't consume a lot of electricity. Even freezing the bottles won't add any electricity cost because the freezer is always on anyway.