[Mustanley]

What would everyone suggest I add to my chiller loop to lower the freezing point and prevent scum from growing in the coolant? Right now the thermostat keeps the distilled water between 6 and 8 degrees celsius. I'm planning on removing the thermostat so that the compressor runs all the time, but I have no idea how cold the coolant will actually get.
I've got some pretty pink colored propylene glycol based antifreeze that I am considering. What are some other ideas? Water wetter? Other particular brands of antifreeze? Isopropyl alcohol?

[nealric]

standard antifreeze works best for me- i just used the pre mixed kind.

[tgp]

antifreeze starts to get slushy at really cold temps (-20 and lower). everyone i know uses methanol. its cheap but kind of dangerous. mix it with water like 70w/30a would be ok i think.
would want to keep it in a sealed res tho, smells pretty bad.
but if your just around -10 - +10 range anti freeze should work ok.

[Mustanley]

I'm not using any kind of res. It's just a closed loop with a T fitting for filling. I think the total volume of the system is about 2 liters.

[nealric]

well, there is more than one variety of antifreeze. You can get anywhere from 0 to -80.

[tgp]

Originally posted by nealric
well, there is more than one variety of antifreeze. You can get anywhere from 0 to -80.

true. but anti freeze means 'not to freeze' right? well, it might not *freeze* but its starts to get the viscosity of something like oil at those temps. using that temperature liquid at that thickness will kill a pump quick.

[nunez1980]

well the main reason why anti-freeze is not recommended, they are many treads on the topic, and they have done the test already,

is because anti-freeze is really design for use in cars, where it can be use in winter and summer, in winter the car is cold at start but them it heats, when anti-freezes works in a heated environment thats where it shines, it was not design to work all the time in coldness...

I really recommend windshield wiper fluid,
A. mediun temps, W. fluid+water
B. Lower temps, straight W. fluid
C. Very low temps, straight methanyl-which W. fluid contains

[Mustanley]

I tried the propylene glycol and the results were poor. I had about 2/3 of a gallon of distilled water in the system. I removed 2-1/2 cups and replaced it with 2-1/2 cups of the propylene glycol antifreeze, let the pump circulate and mix it for about 20 minutes. Then I removed the thermostat tube and let the compressor continue to run. Once my probe thermometer reached -2.5C, the mix apparently froze in the evaporator, cause my computer temps started shooting up and then it hard locked. I waited a few hours for the coolant to thaw and everything seems to be fine again. My die temps are higher now with the antifreeze, so apparently it does hurt performance somewhat.

[nunez1980]

Originally posted by Mustanley
I tried the propylene glycol and the results were poor. I had about 2/3 of a gallon of distilled water in the system. I removed 2-1/2 cups and replaced it with 2-1/2 cups of the propylene glycol antifreeze, let the pump circulate and mix it for about 20 minutes. Then I removed the thermostat tube and let the compressor continue to run. Once my probe thermometer reached -2.5C, the mix apparently froze in the evaporator, cause my computer temps started shooting up and then it hard locked. I waited a few hours for the coolant to thaw and everything seems to be fine again. My die temps are higher now with the antifreeze, so apparently it does hurt performance somewhat.

you should try windshield wiper fluid, it should give you better temps

[Mustanley]

Thanks nunez1980. I see you've been hard at work replying to extreme cooling threads.

[Mac]

hmm for ambient water, is prestone antifreez good?

holy crap i just noticed nunez's name on every thread as 'last post'

cool

[Mustanley]

This propylene glycol stuff blows. My load temps have increased from 25C to 29C, so I now I have to drain everything and replace it with either h20/methanol or h20/windshield wiper fluid. My question is, don't many types of wiper fluid contain amonia, or is that just found in household glass cleaner?

[Nebulous]

I've always used methanol. The stuff i get doesn't contain amonia nor detergents. Several caps of WW and i'm good to go.

[dreammmatt]

a lot of people use antifreeze, but the stuff does get thick, and it also isnt exactly the best coolant...from what i've seen windshield washer fluid works best

[Paxmax]

Hehe, yeah, doesn't the wiper fluid come with a nice scent too? Some lemon maybe? Then you'll soon know if it leaks!