Poor man's Peltier

[blueonblack]

I came across a used Coleman 12-volt cooler at a flea market today. I've been wanting to dissect a small dorm refrigerator or freezer for some time now to experiment with cooling options, and here was one that was already set up for 12-volt DC. At $20 I couldn't pass it up.

The first thing I noticed while testing it was that it would heat as well as cool, depending on how you hook the power wire to it. "Must be a heat pump", I said to myself.

I cracked the top cover off to find this tiny blower and an aluminum heat sink.

Now I knew I wasn't going to find the tiny compressor, condensor and evaporator that I was hoping for. After much prying I popped the heat sink off and presto! Peltier.

After complete disassembly here's what I ended up with. (I've removed the motor already as it was not needed and very noisy.)

I must not understand the Peltier setup. I thought when power was applied one side of the plate got warm and the other side got cold. When I turn this one on one side gets warm and the other side gets hot. I reverse the connections and the sides reverse. There was another heat sink on the bottom of the plate inside the cooler so it's obvious how it was supposed to work, but I'm not seeing how it will cool anything if both sides get warmer than ambient. Maybe the reason the warm side gets warm is because I don't have a heat sink on the hot side and the heat is bleeding through? If I can take the heat away from the hot side effectively will the warm side drop below ambient? Can someone educate me? Or is this thing just broken?

[billygoat333]

interesting idea, using one of those coolers for your computer! as for whether its busted or not, too bad you didnt try it before taking it apart! I wish I knew more to help you, but I don't. :S

[crenn]

http://www.heatsink-guide.com/peltier.htm

[Omega]

What you do is put the heatsink on the hotter side and it will make that the hot side and the other one the cool side.

[blueonblack]

http://www.heatsink-guide.com/peltier.htm

Wow. That is an extremely informative site, thanks very much! +rep

[nevermind1534]

When I first saw the title, I was thinking Perrier.

[Spawn-Inc]

the link from crenn says it all. Peltier are often used with water cooling, they get sandwiched in between the block and cpu/gpu. here is one from swiftech that come with the gpu block.

http://www.jab-tech.com/Swiftech-MCW...s-pr-3415.html

[Twigsoffury]

they bleed condensation like you wouldnt bealive.

I remember hearing something about it getting hot before it gets cold.

but dont hold me to that.

[si-skyline]

PELTIERS CAN BE VERY DANGEROUS! if motherboard and heatsink is not properly insulated with grease and other materials

i wouldn't recommend playing with one before knowing the fundamentals.

you are correct that one side gets warm and the other gets cold, you need to know what side is what before attaching it to a chip. and the hot side will go on the heatsink either a fan, waterblock or other cooling device. To find out connect the peilter to a psu via the +12 (yellow wire) and the gnd (black) for a split second. doing for alot longer can damage it beyond repair.

one important factor what goes into this kind of cooling is the "delta-t" what is a forumla that will tell you the differance in hot and cold sides to see how it would cool. if you can i would see what watt it is and see if it is worth having

hoped that helped, there is plenty of tuts on the net about peilters also look at tecs what is also another cool cooling solution for the crazy's