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Why don't people use alcohol instead of antifreeze?

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Ragnarok

Registered
Joined
Oct 16, 2002
Location
UW, Seattle
Bear with me on this.

Running water alone in a system leads to a buildup of algae and related mono-cellular crud in your waterblocks. Ew.

Antifreeze kills, and I've found that people can smell an amazingly small amount of antifreeze. It's kind of cool at first (it kinda smells like silly putty) but there are reports on the forums of antifreeze giving people headaches... maybe on account of it being poisonous and all.

My watercooling system isn't hermetically sealed, so for me, ethyl glycol is not for the win, and let's say I don't want to buy water wetter. Why not alcohol?

Water has a thermal conductivity of 0.6 W/m*K. Alcohol is only 0.14, so a water/alcohol mix wouldn't cool as efficiently as a pure water mix.

My question is, does anybody do this? How much alcohol do you use?

Thanks.
 
AFAIK, many people use alcohol. If you have acryllics in your loop, it's not smart, as it eats at acryllics.
 
And alcohol has a lower boiling point than water so you will have it evaporate out of your system fairly fast too, since you aren't running a sealed system. And I wouldn't recommend trying to seal the water loop either as the pumps used aren't rated to deal with pressurized loops and you could have water leakage problems.
 
It sounds like you need to use Propylene Glycol, aka RV watersystem antifreeze.
It doesn't evaporate as easily as alcohol or Ethylene Glycol, and it's non-poisonous...heck it's a food additive. It's in the twinkie you had for lunch.
 
Ethanol aka alcohol is only about two carbon atoms differnt to ethylene glycol aka anti freeze so you kinda had a good idea...

Ethanol will kill bacteria better than ethylene glycol another good part to your idea....

The ethanol however will be absorbed by rubber (your rubber o rings on your res etc etc) it will replace the moisture in the rubber with itsef and then evaporate really fast (like 100x faster than water). Over time the rubber dryes up and starts to crack then you get a leek aka zap zap no pc for you.

How fast this happens depends on how much ethanol you use (v/v), and what the temps are like aka how fast evaporation takes place.
 
It depends on the rubber type too. Ethanol would probably be the safest of alcohols too. However, you just don't know what types of plastics or rubbers are being used in those pumps. If I knew for sure that HDPE or nylon was being used, I would have no problem using ethanol up to 50% concentration. most rubbers are not quickly deteriated by ethanol but you just don't know whats in those pumps. Ethanol would probably turn clear tubing white.
 
Ethonal is used in chiller loops, you use metal brazed blocks with it (no rubber) that and freezing temps are far from kind to rubber ;)

SolidxSnake said:
as it eats at acryllics.

Do you have any links? (It doesnt really make common sence, acrylic/plastics are used to store alcholic beverages and thats what ethonal/DE alchol actually is with a ingredent to make it undrinkable)
unless my brain is missfireing at this hour :-/
 
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Here is the major reason why we don't use Alcohol for cooling:

Specific heat of water: 4.186J/g
Specific heat of Alcohol (rubbing): 2.56J/g

Water can absorb a lot more heat than alcohol can. :beer:
 
I just tried to melt some cast acrylic with 50% iso and it didn't do anything. Kind of weird.
 
Ragnarok said:
Bear with me on this.
OK, I'm trying.

Running water alone in a system leads to a buildup of algae and related mono-cellular crud in your waterblocks. Ew.
I did try...really... but I just can't help it any more.
WTF kind of water are you using?
For the past 3+ years I've been watercooling several systems and have never seen the slightest indication of biological growth- and certainly not algae- in any of my loops.
I use distilled water (nothing special, just the $.69/gal. stuff from the grocery store...my Mom used to use it in her iron...) and a variety of additives (everything from WaterWetter to Pentosin/Zerex) and only once did I ever see any gunk at all in a loop- and that I'm convinced was just leftover flux from an improperly flushed radiator, certainly not biological.

So what is this obsession with "algaecides", etc.?
Ragnarok said:
My watercooling system isn't hermetically sealed...
Who's is?
Presumably you do have a normally capped system (i.e. the rez/t-line has a watertight cap and there are no open bleed ports anywhere) and the interior of your case is not exposed to sunlight, so whence the growth?

Just curious, that's all.
 
greenmaji said:
Ethonal is used in chiller loops, you use metal brazed blocks with it (no rubber) that and freezing temps are far from kind to rubber ;)



Do you have any links? (It doesnt really make common sence, acrylic/plastics are used to store alcholic beverages and thats what ethonal/DE alchol actually is with a ingredent to make it undrinkable)
unless my brain is missfireing at this hour :-/

It's methanol and iso that will eat acrylics. I don't know about EtOH but I believe it's a little more safe on acrylic. Alcoholic beverages are stored in PETE or HDPE plastics will are highly chemically resistant.
I forgot about the whole specific heat thing w/alcohol. I was thinking of alcohol being used in regards to viscosity when mixed with water.

Hey moto, let it sit in that mix for several days and see what happens.
 
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alcohol doesn't eat acrylics, but rather the glue/solvent used to hold the peices of acrylic together (example: acrylic reservoirs), and alcohol also tends to dry out seals (i've seen 2 or 3 people who's acrylic reservoirs that have fallen apart and leaked due to alcohol dissolving the solvent used to hold the peices of the res together)



alcohol just isn't a good thing to run in your system if it has o-rings, and if you have acrylics in your loop, NEVER, EVER run alcohol in it
 
Alcohol has been used for years as a cleanser for rubber. Windshield wiper manufacturers still recommend cleaning a new blade with alcohol before installation. It's definitely not a good thing to have floating around in your rubber sealed plumbing.

More info from: http://www.osha.gov/SLTC/healthguidelines/isopropylalcohol/recognition.html

PERSONAL PROTECTIVE EQUIPMENT

Workers should use appropriate personal protective clothing and equipment that must be carefully selected, used, and maintained to be effective in preventing skin contact with isopropyl alcohol. The selection of the appropriate personal protective equipment (PPE) (e.g., gloves, sleeves, encapsulating suits) should be based on the extent of the worker's potential exposure to isopropyl alcohol. The resistance of various materials to permeation by isopropyl alcohol is shown below:

Material Breakthrough time (hr)
Butyl Rubber >8
Nitrile Rubber >8
Viton >8
4H (PE/EVAL) >8
Neoprene >4
Teflon >4
Polyvinyl Chloride Caution 1 to 4
Saranex Caution 1 to 4
Natural Rubber <1(*)
Polyethylene <1(*)
Polyvinyl Alcohol <1(*)

(*) Not recommended, degradation may occur
 
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Sneaky said:
alcohol doesn't eat acrylics, but rather the glue/solvent used to hold the peices of acrylic together (example: acrylic reservoirs)
This doesn't make any sense because the solvent adhesives made to bond acrylics and like-plastics work by acidically roughening the two bonded edges, liquifying them, and then the solvent evaporates out making a fused joint. The only remaining solvent would take the form of dissolved bubbles in the joint.

ALCOHOL CANNOT DISSOLVE ACRYLIC. This is a myth. I've done my own testing of this and have yet to see any marring, discoloration, or degradation. I have also not seen any claims of this being a problem. There are plenty of other chemical-based cleaners that will eat acrylic though so you do have to be picky about how you clean plastics. Acetone for example WILL dissolve most plastics fairly quickly.

But alcohol wouldn't be an effective additive unless your loop was almost entirely metallic and non-porous.

Alcohol (as shown in the previous post) is also very pervasive as a penetrate and will leech itself into a wide variety of porous and semi-porous materials. Alcohol for consumption is stored and transported in glass bottles for this very reason.
 
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Acrylics are not resistant to alcohols. Alcohol may not dissolve acylic but maybe I should use the word "Attack" instead. First it will haze the acrylic when subjected to it for days, depending on the strength of the alcohol. Eventually cracks will develop in the acrylic. It will do the same to polycarbonates too. Dip your cd into isopropyl and see what happens to it. I would never combine acrylic and any alcohol.
DCM is what is used to bond acrylic because it melts it very quickly, they are not using alcohols to do that.
Isopropyl alcohol is fairly safe to use w/o gloves. I believe it's methanol that can be absorbed in very limited amounts through the skin.
Polyethylene (High density) is too resistant to alcohols and can be store it for months to years w/o problems.
 
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SolidxSnake said:
AFAIK, many people use alcohol. If you have acrylics in your loop, it's not smart, as it eats at acrylics.

10-4... Not too sure what material my little propeller in my flow indicator is (was) made of but the alcohol I added to my coolant mix made the prop swell and then it would no longer spin. I added about 4oz to a gallon of distilled water.

I have read that some use peroxide to control algae and what ever else may grow in the loop.
 
Hi
I don't have much to add except for a few things.
Alcohol is what welders call a vapor degreaser. Because it does that. It will upon evaporation aid in removing grease. I use it all the time. If you aren't using anything else to make sure you don't get corrosion i can't see how alcohol would be a good thing. That being said it will evaporate too quickly for it to be really useful

Im in the air force. We are told not to use alcohol on our gas masks to clean them. Not because it destroys the plastic but because it turns our lenses yellow over time. Not sure how much of that is real science or how much is just someone trying to make a change for the sake of change(i mean it is the military) but a few years ago we stopped using it. I've seen a lot less yellow gas masks.
As far as algae goes. Gross. I don't know what you guys are doing with your watercoolers to make em glow those cool colors under the black light but if it is making your watercooler into a petri dish you might want to stop.
Alcohol doesn't eat plastic. acetone(as captain slug said) is that culprit. i know i accidentally put my glasses down one night in a little bit my girlfriend spilled..i woke up and my glasses were all eaten up.,

Hey has anyone ever tried just a drop of bleach in their water cooler? i mean literally 1 or 2 drops should be enough to kill anything in it.Would it hurt anything?
 
Glycols, Water wetter, Zerex or any other type of additive like them are NOT for killing biological growth, bacteria can grow quite happily in a 50% glycol/water mixture. It's there to prevent galvanic corrosion and in the case of Zerex/WW and the like, lower the surface tension of water.

To remove biological growth from your system, use Iodine solution, a few drops in an average size loop will totally prevent anything from growing. Some people use aquarium anti algae too with good results.

Don't use a mix of just water and anti freeze and expect to have no bio growth, or we'll soon be replying to your thread on how to clean gunk out of your storm nozzles.
 
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