Using a 50-80W peltier as an air conditioner - Quick suggestions needed

[The Pentium Guy]

Some quick suggestions would be appreciated.

I'm planning on using a peltier as an air conditioner essentially, approximately what wattage range should I be looking at? I figured somewehre between 50-80W.

http://www.frozencpu.com/exp-02.html

Will that be enough for a simple air chilling effect? Try about a 5-10F drop from ambient.

Thanks,
-The Pentium Guy

[wittekakker]

I suggest u are going to cool something very small like your pc case. First, u are going to have to make the case 100% airtight. Every bit of air that is escaping will just be lost energie and u will loose the chill-effect. U will also need some isolation like with fridges. Next, u'r case will have zero airflow, so the TEC needs enough power to cool ALL components that are producing any heat. Don't think a 80W TEC will be able to do that.

[Holst]

You will have to explain the application further before we can advise.

If your making a beer chiller or something then 50watt will be plenty, but as witte says it all depends on the heat load and insulation.

[The Pentium Guy]

Gotcha

Basically I'm just giving the current CPU heatsink a bit of a boost by directing the chilly air towards the heatsink. I just have to make sure I deal with condensation.

I'm not really looking for an overall case-cooling effect though, the air taken from the cold side will just be blown/ducted to the heatsink.

[wittekakker]

Oh, like that... forget it :)

[The Pentium Guy]

Does that mean it's a bad idea?

[Trigger]

No it does work. Check out some of the reviews on the peltier based case "A/C" systems. They do work to a point,there is only so much an 80w pelt can do though. I wouldnt expect anymore(of a drop) than 3c but you may be able to squeeze a bit more out of it.

[Mr. Tinker]

bad idea.

[wittekakker]

Yes, well, that's my opinian. Chilling air needs a lot of energie (look @ aircondinioners). Air is not good on taking up heat or getting cold. Putting it between heatsink and cpu will do better (if your cpu isn't high wattage and the heatsink is good enough to get away all the power). Even when using a TEC to chill water isn't so good as TEC between waterblock and CPU, and u must know water does a lot better then plain air on transporting heat. When u put the TEC right on your cpu u get rid off any other medium that can have negative effects. U will still need a piece of copper between it, because of the difference in surface area (big TEC, small CPU die), but copper is somewhat the best u can get without paying a large amount of money.

[Holst]

I suppose if you put the pelt in line with the case, and had a heatsink on the outside of the case and one inside.
Then ducted the air from over the inside heatsink onto the CPU you "might" get a few*c drop.

But its not going to be very efficent..

If you allready have the bits then it wont hurt you to have a play .. just dont expect too much.

I woudlnt worry all that much about condensation, just make sure any drips dont fall onto a towel when you are testing ....

Dont try and use that tiny TEC on your CPU ... it wont work at all!