Thermoelectric cooling (TEC) combined a liquid cooling system (LCS) module for lower temperatures

Question

I have a new liquid cooling system (LCS) on the way (XSPC RS360 and Raystorm Kit), and it seems like a shame letting my good nick CM V8 cooler go to waste. So in pulling a few new and old pieces together I am considering using the thermoelectric cooler/Peltier effect to reduce coolant to a below ambient (but above the dewpoint) level by sandwiching a 250 W thermoelectric cooler (TEC) slab between the V8 and a cheap waterblock.

I have seen dribs and drabs on enthusiast forums, but I haven't seen anything as specific as cooling an LCS with this technique.

Note that this will not be for a 24/7 setup. Only when it gets warm, or when I need it for some fun overclocking. Thus I am thinking of using a few quick disconnects in the loop to accommodate a modular nature. This is all thanks to the high draw such a device has on current.

Are there any shortfalls with the plan?

So far, I will need:

• Old 12 V laptop/PSU
• TEC device (eBay)
• Waterblock

Answer 1

I may be misunderstanding your question, but are you proposing the following layout?

 
                    Hot water in from rest of loop
 ____________ ___ __|_
|            |   |    |
|     V8     |TEC|WTR |
|(aircooling |   |BLK |
|_____TEC)___|___|____|
                     |
                     Sub-ambient back into loop

If so, then I don't see that working very well for you. In order to cool your loop's fluid to below ambient, even at idle, means your TEC will be pushing a lot of extra heat than the V8 can handle. I really don't see a situation where the V8 would give you any benefits over, say, the following layout:

Dual Loop TEC design:


  Cool water from large radiator(s) 
  | 
  |          Hot water in from rest of Computer's loop
 _|__ ___ __|_
|    |   |    |
|WTR |TEC| WTR|
|BLK |   | BLK|
|__1_|___|___2|
  |           |
  |           Sub-ambient back into Computer's loop
  |
  Hot water out to large radiator(s) 

The main reason for using TECs is because it allows for active cooling, and distances your loop's temperature from ambient. Water will remove more heat from hot water than just warm water. Instead of the above layout, you could just sandwich the TEC in a traditional way, between your CPU and the CPU block. This would eliminate the need for another loop, but consider the following:

• It will be hard to keep the temps above the dewpoint, and if it drops below, you'll get condensation around your CPU socket (unless you coat everything in silicone or another insulator)
• The TEC will only provide sub-ambient cooling to the CPU. In the layout above, the entire loop will benefit from the TEC. If you are only planning on watercooling your CPU, then this is a non-issue for you.

Anyways, good luck!