Quote Originally Posted by Uncle Jimbo View Post
I have similar experience - but I was maintaining constant temperature for sensors on oil rigs. The gear could end up on a north sea platform in the dead of winter, or in Africa in high summer. We needed to maintain 25C plus or minus 2 degrees for the electronics package to assure the stability of readings.

One thing for sure - in a TEC setup, you will not see better than 40% efficiency and probably a lot less. For high efficiency cooling of water, I believe the best way is to just use standard air conditioning or refrigerator components.

The advantage TECs provide is the ability to provide tight temp control, and also to provide cooling with a small physical size and better packaging options. Going way sub-ambient is not an option with water and messy with phase change, but fairly easy to do with TECs - attached is a shot of a cooler I helped my nephew build which delivered air at around 5C to a 100W heat load with hot side air cooling. But it used nearly 300W to do it, so the air cooler had to unload around 400W. The Blue Orb is the cold side - it provided air at 5C to a Vanessa cooler on the CPU and generally cooled the air in the whole case. The hot side has a giant Melcor sink which has .08 C/W with 120CFM. Not shown is the drip pan <G>. An interesting project, but for the small improvement in temp at the CPU, done a whole lot quieter and with a tenth the power using a small phase change unit and WC...
Word.