Cooling Yet another peltier question...

Hello,

I just read a few articles about peltier cooling the CPU, and I just had an idea (dumb perhaps): What if, instead of cooling the CPU, just put the peltier on the reservoir (which is a few inches away from everything the maybe harmed by condensation) . Now, certainly it wouldn't give the same amount of cooling as if it would be places directly on the CPU, but it can help preventing the water warming (after using the computer for 72 hours straight).
So my basic idea was: put the peltier on a reservoir (inox one), place a heatsink on the pletier and finally the heatsink will be placed in a "cooling tunnel" (a large tube with two fans, one pushing and other pulling the air outside the case).
What do you think about that concept? Please, I need some clarifications as I'm new to wc and also this forum

 

Sounds like it could work - but the thing here is that any temperature below your case will create condensation (clearly, the bigger the difference in temperature, the more condensation). So you could use it to make sure your water is exactly room temp, but you couldn't drop it to say 0'C.

Although I'd get someone else's opinion of how greater temperature difference you need for a significant amount of condensation.

 

In fact, a temperature probe will be fixed on the the reservoir (or directly into water) and once the temperature reaches, let's say, 20C, the peltier will begin to work and as soon as it reaches again the 10C it's will turn off. That was my initial plan.
Any suggestions are welcome!

 

hmmm sounds like a plan but if you think aobut it a little im not sure if it will actually do anything, what your saying is yoru goona try and cool the res down witht he pelt and use a heatsink to cool the pelt. Well to get a good cooling of the rest you'd have to creat a box with fins in it so that as much of the water touches the TEC if you know what i mean but still thinking about it im not sure if it will do anything for you, better of putting the TEC directly on the CPU.


morgan.

 

It would be better to use a comparator and 2 thermocouples and have it turn off when it is right at ambient, and on at ambient+5, since chances are ambient will be above 10C you could still have condensation.
But honestly, I think that you will have trouble getting the water to ambient in the first place (or keeping it there, more correctly). If you have the res after the rad thouyhg this could let you quite possibly achieve ambient though. Remember as the temp of the water approaches ambeint, the less effective the rad is, and the more work the pelt has to do. Also, CPU makes 60-70 W of heat, and you would need a pretty big pelt to do that, 150W +, and that would have ~210 W of heat to dissipate, how are you going to dissipate 210 W of heat? Imagine, a PAL 8045, that can handle a small pelt, but a large pelt would have to make that thing hot to make the transer efficient enough that all 210W can be dissipated, raising the min temp of the water.

I would say do it and see if you can get ambient.

EDIT:I can't wait till coolchips finally goes retail.

 

http://www.h2okoeling.dk/images/Artikler/skema.JPG

nice one.. relative humidity on X, temperature on Y. condensation forming where they meet
I thinkyou would be better off sticking the pelt to a waterblock than a res.. just a simple block should do and perfor better..

 

This wont work. People have tryed waterchillers before but because water has such a high heat capacity it takes a lo of heat removal to decrease the temperature. If you wanted to try this then i recommned you use a rad first to get it close to ambient then use pelts to chill it. A single pelt will NOT be able to keep water at ambient on its own, but with a rad before the pelt youd probably be below ambient. Using a rad before will also prevent the pelts from going too far - if you use enough to acctually get it below ambient the rad will help keep the temp near to ambient so you wont get major condensation over everything. If you go ott with pelt waterchilling best remove the rad though.

Think of your electrisity bill? youd need about 500w worth of pelts to get respectale temps on there own...

 

What you are proposing is to chill the water with an aircooled pelt, and it will be hard to remove that much heat with air. It will certainly make hella noise.

If I were going to do this I'd have the pelt sandwiched between two separate water loops. So you have your "cold" loop which goes res (cold side of pelt) --> pump --> blocks --> rad --> res (or better yet have 2 rads, one before blocks and one after) and you would have a "hot" loop on the hot side of the pelt, going pelt --> rad --> pump --> pelt, or similar.

All seems a bit too much like hard work just to get ambient temp water. Just put a peltier on the processor and one on the gpu, take the normal anti-condensation measures and run a normal watercooling loop on top of that. Or get a vapo

 

Thanks alot for all the comments, it's really appreciated.
But the basic idea was to have a normal watercool loop (with heatercore) and then to add to it some kind waterchilling mechanism. Here in Montreal, summer is a quiet hot season. It's not abnormal to get 35C, so if your water gets around 35C + the CPU , GPU and northbridge heats you have a problem (even with mild overclock )
So I decided to implement a peltier (which is temperature controlled (which will work only when it's necessary to bring the water temperature a little above ambient and then stop))
I will upload a little scheme of the system for your approbation
Stay tuned...

 

What about using a phase change waterchiller? get an old freezer and set the thermostat for about 3C over the max ambient you will ever have and it will work well. Uses a lot less energy than pelts too...

Or you could stick your rad outside, which would probably be better than pelts inside, you could stick as many fans on it then as you want.

 

Oho! Nice idea as well! Thanks!!!
But my over concern, is the sound. I want this case to be as silent as possible. And I suspect that those early 20th century phase inverters are reproducing quite faithfully the modern jet
No? How noise are they actually?

 

My housemate's vapochill phase effort doesn't sound any louder than a usual system. There's a single fan on a 120mm rad. I'm also guessing they don't put the best/quitest fan on the thing either.

Not sure if the condenser thing involved makes much noise - but it's not noticable over his 3 case fans, northbridge and GPU

 

Thanks for the great idea!
You see in fact I want the quietest and safest system possible, because I build a custom case for somebody, and I certainly don't want to ruin the high end pieces that will put in that case So you're suggesting me to chill water (not the CPU) with phase inverter? Could you please send me a few link which can clarifie the process of installation and exploitation of that marvelous invention of humankind?
Thanks in advance!

 

peltier cooling is the cooling system with two differently conductive metals, right? pass a current through and one cools and another heats, right?

do they need to be connected? or can the cold block of metal be on the CPU or whatever, and connect a cable to the hot block?

this might sound dumb, but i had an idea for a toaster in a computer. it would be really cool if i could use a peltier to do it.

 

I finally found some proof, that my idea was not so bad after all! Even if it proved by the same occasion that it wasn't new
http://guides.pimprig.com/water_cooling/efficient_water_chiller.php

The concept with VapoChill system is attractive, but if you look deeper it has a few major drawbacks:
1) Cost
2) Complexity (when you move it, you should be extremely careful and not let the lubrificant from the compressor flow into the condenser)
Plus, if you want to make that system from scratch and scrap, you should have a Ph.D in thermodynamics. But the advantages are certainly awesome...

Well anyway, I'd like to hear some comments on that link above!

 

This is almost exactly what I was thinking of doing. Except I wanted to ditch the radiator all together. I am a newb to WC but I figure hey what the heck why not. If it doesn't work I could make a slick drink chiller out of it. I wanted to do something similar to what you suggested in the beginning of this thread AhPuch.

I have aquired 8 identical P4 heatsinks and was gonna fuse all of them with solder to a copper plate. They would be positioned in a 2x4 array. I have 2 120 watt peltier that I wanted to power with a spare PS that I have lying around, it is a crappy 420 but it can give enough juice to power the peltier. I was going to build a custom waterblock that would attach to the cold side of both of the peltier. I was going to dissapate the heat fron the heatsink array with 2x120mm fans on top blowing air down on the heatsinks, and 8 smaller fans that came with the heatsinks (4 on each side) of the array sucking air out. Hopefully this would dissapate the heat generated from the peltier.

I have the dimensions worked out and it will all fit nicely on the top of my case. I just need to get a few more components and I can hook it all together.

Also I want the fluids to be VERY cold. I was thinking I could fill in the space around the custom waterblock with the material that mouse pads are made from. I would also insulate the piping and waterblocks that were on this system. Thus avoiding condensation.

 

swiftech makes a water chiller, MCW-CHILL 452™ Thermoelectric liquid chiller , so it must work to chill your water, but it seems expensive.