Phase Change + Pelt = Lower Temps

[Time4aMassiveOC]

heya all, so i have my ac all bent up and in a rez , tommorow i am going to go get some denatured alcohol so its about time to start ordering waterblocks

so im going to get a 6002-lga775 for my processor block since its all copper

but i saw the cpu block they make that has a 226W pelt "thermoelectric" waterblock

http://www.sidewindercomputers.com/swmc7.html

since i can expect my chiller will probly do between -20 to -30C under load so the fluid will be around that temp when it goes into the pelt block.

so i was wondering what kinda temps will be the pelts lowest possible output?.

i also know that it would be just dumping heat into my cooling loop that would be on my videocard too however i looked up the compressor and it has plenty of capacity that will support a little over 500W. i cant quite recall but i think airconditioner btu rating is BTU@0C. i think i should be able to maintain below -10C coolant temps with a 400-500W load.

anyway you guys input would be appreciated.


by the way does anyone know of any pelt blocks for 7900 gt / 1900xtx models? i saw one that was for 9000-9700 models but i dont think those could handle a 7900 or 1900

 

[Gautam]

At those temps, the pelt will be so inefficient, it wouldn't even be worth having. Just stick with the chiller only for optimal temps.

If you use enough coolant, a heavy subzero load will be no problem.

 

[Time4aMassiveOC]

is there such thing as pelts designed to be cooled down into the sub zero range?

 

[veryhumid]

why not go with a newer, better performing block like a storm or apogee?

 

[XDVD]

Careful.. I burnt up a Fortran 550 PSU trying this. I had a single stage on a pelt and I guess the pelt made so little resistance as it cooled that it pulled a crapload of current causing total meltdown. The TEC never worked again either.

 

[Pf.Farnsworth]

so i have my ac all bent up

I assume you just bent your self a chiller form an existing ac unit? Your coolant temperatures with load will be about -15C / -20C.

By the way a chiller/pelt combo is pretty useless, they are not really made for that application. Chiller alone will get your better results and at about 1/10th of the power bill.

why not go with a newer, better performing block like a storm or apogee?

Because they are to restrictive for a chiller as the coolant at low temperatures gets thick and you need a nice pump. And by nice I mean something like Iwaki RD30. And still no real reason to go to such a block even if your pump could push it since you wont gain anything from it. Chilled water loops dont function exactly like ambient loops, its not a linear relation. The top is derlin and will get very brittle. The rubber seal will frezze, break and leak. Not the best choise. Swiftech 6002 is still the best option. You can use some other non restrictive blocks with brass/copper tops but make sure to take the rubber seal out and braze them shut.

 

[Time4aMassiveOC]

curiosity still begs the question, what is the lowest temp that the pelt could achieve given that the coolant could be any temp -15C and warmer?

im guessing that it probly wouldnt get much colder than -30C since thats where the chart bottoms out at near 0 load.

 

[greenmaji]

A proper charge on the chiller should hit -30C soooooo its kinda moot. You will not going to get a better temp, and your going to need to sacrifice effecency of the chiller to make the system (with TEC) operable.

 

[Pf.Farnsworth]

Frankly dont see the point. If you are making a chiller to cool your pelt I assume you will be cooling more then one heat source, that means a few pelts. I dont see you gaining any preformance and only punishing yourself with a large power bill. I dont think you will see -30C with load, but if it does still pointless since a good chiller can get colder with much less power draw.

Green, the charge doesnt guarantee anything. Give it the right charge and you get your temperature, no, it doesnt work like that. If you want to see good preformance on a chiller you need to worry about many more things. You need to think though every inch of your plumbing to maximize efficiency. You need to step up to plate heat exchangers, none of that coaxial copper pipe in a bottle crap. You will need to play with your refrigerant blends. You will probbably need to step up to a water cooled condenser to controll the pressures you will have with the blend you will need. This is what I am trying to do right now, build the best chiller I can. So far I am $2000 in the hole and still working. I will post my creation when its is 100% finished, I hope it will turn some heads.