Mini freezer for reasonable heat load

[Johnny Bravo]

Hi guys have been knocking an idea about that having difficulty seeing if it is valid or not so was wondering if I could have your input.

I'm knocking together a dothan setup and plan on overclocking it pretty hard. Initially using aircooling then water and finally chilled. For the last stage I was considering using a peltier but then considered the use of a mini FREEZER (note not fridge) as a means of chilling the cpu. Basically the same idea as the mini fridge- coils of copper piping inside and then attach water/anti-freeze loop externally.

Thing is alot of other folk have attempted this idea with a fridge and as correctly pointed out the thermal load they were trying to dump was greater than the fridge could cope with. So I was what if a freezer unit is used? Does the same principle arise to due to the lower thermal load (dothan overclock runs cooler than P4/A64 overclock) and use of a freezer unit. I'm not aiming for sub zero temps just below ambient.

What say ye?

Cheers

John


BTW the freezer unit is the Naiko NHF40 I can't seem to find a data sheet for it tho :(

[MIN_Roadkill]

Open it up and get some specifications from the compressor.

[IYP]

freezers are still not designed to tackle a constant heat source.....isnt any diffrent from a fridge in load handling....just gets a little colder

[Johnny Bravo]

I was assuming as much IYP cheers anyway

[mozzartusm]

Just about every thread that I have read on this subject is against the idea, however I have been using a 5 cubic' compact freezer for around 3 or 4 months and have had no problems. It doesnt even run 24/7. The trick is using a very large res inside the frezzer. I use around 5 gal inside mine. The res is a small narrow trash can thats made of plastic. Using a metal res would be much better. After you get the liquid temps down really low it doesnt work all that hard to maintain them. I use a winterizing anti-freeze thats good to around -50. I can maintian temps of 5 to 10C OCd to 5Ghz.

[Shyfty]

I think it all depends on what temps you are looking to achieve. If you are looking chill sub ambient, but above zero then the freezer idea would likely work. Just make sure you have good air flow across the condensor on the back. What you do want to avoid is short cycling by the compressor or thermal overload, unless of course you don't care whether the compressor dies or not :)

[Johnny Bravo]

Hmmm I was wondering if a were to use a container within the freezer that was filled with a suitable liquid that has a low freezing point that was to act as a heat buffer with copper piping or some form of a heat exchanger submerged in it?

[mozzartusm]

Hmmm I was wondering if a were to use a container within the freezer that was filled with a suitable liquid that has a low freezing point that was to act as a heat buffer with copper piping or some form of a heat exchanger submerged in it?

Thats exactly what I am currently doing with mine. The biggest problem that you will run into is not being able to turn your pump off. The lines freeze up if you turn the pump off, so its best to leave the pump running even if your not using the system.

[Johnny Bravo]

I'm hoping that will not be necesary as I intend to get a bottle of this stuff (http://www.dangerdenstore.com/product.php?productid=144&cat=63&page=1) to run in the cooling loop. As it has a low low freezing point I'm very doubtful it will ever be reached by the mini freezer. In the freezer itself the thermal buffer will be somthing far cheaper, a 70/30 anti-freeze mix or something, as theres no contamination problems.

On that note, what do you guys think about the use of a coreheater or similar radiator for the heat exchangr, or should I just use copper piping for this task?

Cheers for the help so far keep it coming :toast:

[mozzartusm]

I'm hoping that will not be necesary as I intend to get a bottle of this stuff (http://www.dangerdenstore.com/product.php?productid=144&cat=63&page=1) to run in the cooling loop. As it has a low low freezing point I'm very doubtful it will ever be reached by the mini freezer. In the freezer itself the thermal buffer will be somthing far cheaper, a 70/30 anti-freeze mix or something, as theres no contamination problems.

On that note, what do you guys think about the use of a coreheater or similar radiator for the heat exchangr, or should I just use copper piping for this task?

Cheers for the help so far keep it coming :toast:


All you need is some copper pipe, if your using the freezer to house the res then I dont think that a heatexchanger would help.

[mozzartusm]

You can get lower frezzing point with Antifreeze and its alot cheaper.