evap cooling

[imagex]

I'am just starting to build a evap cooling system to cool two pelt cooled rigs.i am going to put it outside the house and run lines inside.two ways i can do this:
use water in my evap and antifrezze in block,and use two pumps and some sort of heatexchanger. or :use one pump and use antifrezze . But will antifrezze evap? and if does work will it kill my yard? or will just go into the air? hmm? any ideas

[LKraven]

Don't use antifreeze.

Yes, it will (slowly) evaporate, and probably won't kill your yard, but you do not want to be breathing vaporized glycol on a daily basis. It'll end up killing you in a few dozen years.

More immediately, it will kill the neighborhood cats and dogs that will try to drink it.

Now, you may not care about dying in a few years, and you may intend to kill the pesky neighbor's pets, but then consider this:

Antifreeze won't do a damn thing for you, as far as the efficiency of the tower goes. It has bad thermal transport properties (water is much better).

But wait, Neil, why do people use antifreeze in car radiators then?

It's not named antifreeze for nothing. Water will freeze at 0c. Antifreeze has a MUCH lower freezing point. If you live in North Dakota, you do not want to start your car at 5am on a December morning with your coolant frozen in your radiator. Antifreeze also has a much higher boiling point, and prevents exploding radiators on hot days.

Now, lemme ask you a question. Are you planning on running your coolant at below freezing or above boiling? An evap tower will never get that far below ambient that the water freezes. If it does, ambient's cold enough that you probably will get a lot better performance from just a a fan. You'll have trouble playing Counterstrike wearing those mittens anyway. If it's hot enough to boil the water, your CPU was toast a few minutes ago anyway.

Skip the antifreeze. The only possible reason you might even consider antifreeze is to prevent biologicals from colonizing your evap tower. Yep, it'll kill them dead, think what it'll do to you, day in and day out. There are much safer ways keep the water algae free.

Neil

[imagex]

thanks neil,my main reason was so my block doesn't rott out on me. i have cats and want to keep them,what would be good to add to water to condition it that :1 wont kill everything & 2 wont hender my cooling?

[LKraven]

Unless you plan on running hydrochloric acid through your system, the odds of having your block rot out on you is about nil.

Even if you have the nastiest tap water in the country, the worst that will happen is scaling from calcium that accumulates when you turn off your bong (sitting water).

You will notice this start to degrade performance in about 10 years. It won't happen any sooner than that unless you are keeping clamshells or have a habit of crumbling chalk or Tums (glorified chalk, with sugar) in your reservoir.

If this concerns you, buy distilled water or use reverse osmosis water. As for adding some magical yet cheap liquid to your reservoir, be happy that the earth is 2/3 covered with precisely what you need: water.

Neil

[imagex]

well i'm test running my system now,it's made out of a large cooler "rubber maid" with a twin squirrel cage blower mounted on top and a 4 inch air duct elbow at the other end,i found that floor polishing pad work great there about 1 inch thick and 16 inches round.with no load"not hooked to my system" it took the water to 69F from a room temp of 80F ,with a load it keep the water at 81F and my cpu with a 120 watt pelt at 37F ,thats a lot better than my old temp 54F.
so now i just have to refine this thing,but i'll never go back to a rad system!!