Ceramic thermoelectric cooler

[Retrofan]

Hi:
Short thread. I've got a BPPC and I would like to have a nicer and silent cooling.

And I've seen these things: http://www.ebay.es/itm/Celula-Peltie...item25aa66aa1a

My new PSU delivers 3A in the 12v line.

I would like to know how they work. Do they always work cooling -all the time- as I suposse? Then I could add a thermal sensor to switch on when it gets to 45ºC.

I want to know if someone has tried these devices to cool a CPU or whatever.

[Wayne123]

They used to be common options for PC cpu coolers many years ago, one side will get hot and the other cold, you need to pull the heat off the hot side or they just get really hot.

I have played with them many years ago, there was usually a block of aluminum for thermal mass on one side and a heatsink and a fan on the other to extract the heat. I think a good standard heatsink and fan is better, water will condense on the cold side of these when running.

[Locutus]

While you do get a lower temperature on the cpu, you will have even more heat to draw away using a heatsink assembly. So in the end you dont win for getting a more silent cooler as you need to cool more.

[pandy71]

Originally Posted by Retrofan

I want to know if someone has tried these devices to cool a CPU or whatever.

Not for CPU (CCD sensor few years ago).
Basically it is a heat pump - it use electricity to transfer heat from cold to hot side (it may work as cooler or heater).
Cooling efficiency is low (for sure less than 15% - my practical experience shows it is less than 10%).
In theory you may reach 70 C deg difference between cold and hot side (my practical observations showing approx 45 C deg).
I would suggest heat pipe instead TEC.

And yes, as pointed - water condensation as cold side can be serious issue - it is better to keep cold side (if possible) above condensing point (thus efficiency is reduced even more).

Poor efficiency means that for moving 10W power you need to pump for example 50 - 70W electrical power and dissipate in total 60 - 80W heat power.

[Shadowfire]

As has been said: They aren't a very efficient way of cooling something down.
Say, for instance, you have a 30W TEC which transfers 5W of heat from the cold side to the hot side, and your processor typically dissipates 4W of power.

Now, your stock heatsink will need to dissipate 4W of power @ thermal equilibrium.
If you slap the TEC on, the TEC cold side will be cooler than the stock heatsink (the TEC is trying to pull 5W of heat, but you're only producing 4W, so the temperature of the IC will actually decrease until heat leakage from the environment to the TEC rises to 1W, at which point you will have thermal equilibrium. Since you are now colder than the surrounding air, condensation appears.). Unfortunately, you'll notice that on the hot side of the TEC, you now have to dissipate (5W transferred from the cold side, + 30W from the TEC) 35 watts of power, instead of the 4 watts needed by the original heat sink.

Dissipating 35W of power is an order of magnitude harder than dissipating 4W of power. You now need a much bigger heat sink, and probably additional air flow across that heat sink, to dissipate all that heat. Where before you could have used a small heatsink taped on the IC, you now need a monster heatsink, and have turned your computer into more of a space heater than it was before.

Here's what you get:

* Colder CPU temperatures
* Beefier, more expensive power supply (additional load from the TEC)
* Beefier, more expensive heat sink
* Probably going from a fanless design to something with active cooling
-> More expensive fan, probably louder than what you have
-> Additional heat may need case modifications to vent it

If you were looking for "quiet"... two ways of doing that.
1. Use a big, low rpm fan for the heat sink. This will result in the same amount of air flow (and air flow noise) but the fan motor won't sound like a jet engine.
2. Passive cooling using a much larger heat sink.
3. Liquid cooling: Quieter because the radiators usually have large, low rpm fans.

If you're using something internal to an A500/A600/A1200, it's likely that you won't have space for any of these things.

[Retrofan]

Thanks. Yes, I finally added a big 12v silent fan with an aluminum body. It keeps under the accelerator, but the Amiga rests on bigger rubber stands, so with them the fan just touches the ground, but it can breath through the sides thanks to the design. It's a cheap fan anyway: http://www.ebay.es/itm/Aluminum-Heat...item4d28ca403e

[pandy71]

I would give a chance to cooling kits for notebooks or graphics card - they are usually flat and they use usually heat pipes to move heat from one point with limited space to heat sink located in more convenient location (from air flow perspective).