Hi,

I was watching videos in YouTube about how to build "homemade AC". I got an idea to build a relatively silent and condensation free cooling system. I want to cool small space (~0.04m[SUP]3[/SUP]) to a fridge-like temperatures. But I barely know how a fridge and ac work, so I need a bit help on that part. I'm guessing a fridge wouldn't work because it creates condensation inside which is something I don't want and its not made to cool constant heat source which is what I want. The way AC works seems more viable, but I'm sure how to build and how silent its going to be.

I'm not going for something practical, but I don't want to spend to much money on it either. I just want to make it work.

Currently I'm going with something like this: https://www.youtube.com/watch?v=ITtlxjvLQis I'd connect the exhaust of it to the intake of the container being cooled and container's exhaust to the "ACs" intake (where the fan is). It should create a loop of cooling and heating the air. I don't know how cold the air will be and whether its going to be moisture free. There is also the positive/negative pressure problem.

I don't mind research the topic myself, but I don't know where to start from and what is my best bet, so I'm open to pointers and new ideas as well.

 

Forget the ice bucket. You want a peltier plate, fins, some ductwork, a thermostat and a blower.

Duct the air so it circulates from the space you want cooled over the cooling fins attached to the plate and back. You'll need a condensation drain where the cooling fins are.

 

There is a reason most homes use vapor phase air conditioning. It's the cheapest and most efficient way to accomplish the task. Peltier plates are used for seat cooling in cars and small coolers but their inefficiency limits their use. Coolers with ice packs and fans are used as a ghetto method of cooling airplanes on the ramp but they are extremely inefficient and a major hassle considering the benefit they produce and I consider them a gimmick.

You have to think that ice is usually made by the same process the cools most homes. So, using ice as a cooling medium is an inefficient and unneeded step. Blowing air across ice was a viable option 150 years ago when it was the only game in town but it was replaced by more efficient methods long before WWII.

Oh, and condensation occurs independent of what causes it. Any time you cool a gas (air) the potential for condensation exists. It doesn't matter if the source of the cool is compressed freon or ice. Water will condense if conditions are right.

 

What is the constant heat source you are trying to cool ?

 

So read about this peltier plate and it seems the thing for the job.

Something like this:
https://www.youtube.com/watch?v=ML7tr-2YvR8&list=PLt5W4Qkvd_YPpv7m-nbl1upL-hwYInACY&index=17 The problem is, these things are not so common here and they're times more expensive. I'm going to look more thoroughly when I have more time. But thats the general concept? I'm cooling the hot side (I hope copper heat sink and low speed fan will do the job) and blowing the cold air into the cooled space with another set of fan and heat sink? I'm thinking of cooling a PC.

P.S. I build the ice box. xD It does blow cold air, especially using a 220V bathroom fan, but I'll upgrade to 12V fan later on to see how it works.

 

You still have not told us what you are trying to cool or accomplish. There are many ways to cool something. Peltier is one of them. It is not efficient, is limited in power and is limited to how cold it can get.

 

In his last post he mentioned cooling a PC.

 

Oops!

Are you trying to cool the CPU or some other component or the cabinet? Cooling the CPU or video card might be best done with a cooler meant for that task. You can build your own but you need to make very sure you have good contact with the chip you are cooling.

If cooling the cabinet I would first figure how much power your computer consumes. That will give some idea how much cooling you need to provide. You may need more than one chip to cool a desk top computer.

---
Are you in Bulgaria? I was in Varna a while ago and really enjoyed the town and having drinks at the beach clubs.

 

Initially I was thinking of cooling the whole case of the PC. But now I see a lot other possibilities. Still PC cooling is the primary. I have an 6-years old PC, nothing special. I will use as a test subject, but once I found a secure way of doing it, of course.

So, if I direct the cold air from a peltier into the case, it wont be cold enough to effectively cool it? Than what would be my next best option?

Pilot Dane Is it not a small world... Yeah, I'm from Bulgaria. Glad you enjoyed your stay. You should try our food next time.

 

Don't reinvent the wheel, PC cooling systems, many with Peltier plates already exist. Just buy one.