Fridge or AC unit help me decide?

[X-tremist]

Hey guys,
I'm currently debating about whether to use a fridge or an AC unit for my chiller my criteria is listed below. I want the lowest possible temps, but the method has to meet my criteria. Just a question about the AC unit do you run it on and off or continuosly?
Criteria....
-Run with my future waterblock (a block made out of derlin).
-Not be a big hit on the electricity bill

You advice is highly appreciated.

[Çhrist0ph]

AC no doubt. Continuosly on.

[X-tremist]

Continously on? That will be heafty on the electricity bill.
Would the block just crack under those temps?

[Gary Lloyd]

It doesn't need to be run continuously.

[Tonic]

A/C unit is much powerful than fridge.. maybe it's huge watts
eater, but you can build a large reservoir with 20L (just example)
liquid and a good insulation. Then you would cool liquid to low
temperature (lowly as you can), and turn off compressor. This
temperature will keep for few days, it's long time ;)

Copper block will not crack (there were cascades with ~ -100C
on evaporators ;))

[X-tremist]

Here is the block made out of derlin, will it crack?

[X-tremist]

I was told this by someone,
Thats going to be one loud water chiller. RAC compressors (esp. old and free ones ) are pretty loud, not to mention massive power consuption. I'm assuming you intend to use the compressor, not just the coils because you said a working RAC. Could get you one but i'm in perth. Better using a refrigeration condensing unit as the compressors are quiter and cheaper to run

[Tonic]

If this have any plastic, silicone elements, swap these to teflon or
good silicone (for low temperature)

[Çhrist0ph]

Originally posted by Gary Lloyd
It doesn't need to be run continuously.

well, if you have a very well insulated resevoir. If not, temps will just continue to rise after its turned off.

[Gary Lloyd]

Let me rephrase that. It doesn't need to run when the computer is off.

[S_I_N]

Gary how long a time would you guestimate the rez setup on one of your chillers holding the temp unpowered for?

I ask cause I'm thinking I'm going to have to put my new chiller on a timer to have it cool enough to power up once I get home from work.

[X-tremist]

When you guys say well insulated, is inside an esky fine?

[S_I_N]

insulating means wrapping the block and all the tubing in closed cell foam or neoprene to keep the air from getting to the parts carring or handling the cold water. This does 2 things keeps it from sweating and helps maintain the cold water temps you aspire to achieve

[Gary Lloyd]

S_I_N, the coolant in your chiller isn't going to hold temperature very long with the system off, because the res is very small. The other side of the coin is, since the res is small, it will pull down to temp very fast.

[kayl]

the smaller the res the more practical the chillier becomes, i know if i have to wait a few hours for my chillier to cool down just so i can run the cpu at - degs C temps, why would anyone want to use a chillier

[S_I_N]

because we can :D no seriously you can achieve a better overclock. And a good chiller wont need hours to cool down to -temps gary told me the one I bought will get to temp in under an hour. But I sometimes need to get straight on the comp when I get home therefore I'd want to have it chilling before I arrive home say 15-30 mins prior.

[X-tremist]

kayl your from Aus. do you have any idea how much it would cost to run a AC for you?

The fridge idea seems the better one, soley because of the current.

[kayl]

are you from Australia im in perth how about you
here 73w per hour cost 1 cent
so for my air-conditioner water chillier im working on uses about 456w when i measured it that includes the ac fans i have running on the condenser, when it was in the airconditioner it used about 860w, its a 6,500 BTU airconditioner, i think its about 1/2 horse power
so 16 hours cost me $1, once i get good at making these things i will go to a smaller compressor, until then i think im better off with a larger compressor so i can get better results.

[kayl]

and this is a compressor out of a really old fridge freezer i found in the bush, i think its about 1,400 BTU compressor, i hope in the near future to give it another go, past tries in my chillier didnt show good results but i was doing a few things incorrect.
for $1 i should get about 20 hours out of this one, saving it for a direct die, its really really quiet
the old R22 air conditioners are quiet loud


http://www.xtremesystems.org/forums/showthread.php?s=&threadid=34088
its the one on the left