Using car coolant to cool CPU ?!

[kid41212003]

Seems like the safest bet is to use distilled water + additive (to kill growth). Car coolants sound like a hassle.

 

[Gasaraki]

Water is the best coolent

 

[RichF]

1) Frequent water changes accelerate some type of corrosion, from what I've read. So, it seems that it is a common myth that people believe than "cleaner" (fresher) distilled water will keep corrosion in check. Obviously, certain corrosion sources, like algal growth, will be inhibited by frequent water changes but that's not the only source — leading us to:

2) Dissolved oxygen causes corrosion. Water systems with very low dissolved oxygen can last much longer.

3) Distilled water alone will cause corrosion.

4) Silver coils need chlorine in the water to be effective.

Copper and Silver Ionization

Ionization indicates the electrolytic generation of copper and silver ions in cooling tower water. If properly managed, copper and silver ion concentrations at 20 to 30 µg/L and 10 to 15 µg/L,respectively, can be effective to kill bacteria in the systems. The ions assist in the control of bacterial populations in the presence of a free chlorine residual of at least 0.2 mg/kg. It should be noted that in hard water systems, silver ion concentrations is difficult to maintain due to build-up of scale on the electrodes, and the high concentration of dissolved solids precipitating the silver ions out of solution. For both hard and soft water, the ionization process is pH sensitive and it is difficult to maintain silver ion concentrations above pH 7.6. It is not recommended to adopt ionization in systems having steel or aluminum heat exchanger since deposition of the copper ion and subsequent galvanic corrosion is significant.

link

5) Glycol has to be above 20% concentration or it will be degraded by biological activity.

In the case of glycol loops, verifying that the glycol concentration is more than 20% is critical. At levels less than this (for chilled and out of service hot loops), rapid biological degradation of either ethylene or propylene glycol to an assortment of organic acids and intermediate products, will take place.

Source: Water Treatment In Closed Systems — ASHRAE Journal. Darrell Hartwick is the technical marketing manager with Eclipse Chemical Company in Baie D’Urfé, Quebec.

6) Even inhibited propylene glycol removes more metal from the copper surface than distilled water. See attachment 1.

7) Benzotriazole (BTA), tolyltriazole, and napthotriazole are effective corrosion inhibitors for copper. Only BTA is readily soluble in room temperature distilled water.

information about napthotriazole, which may be the strongest inhibitor:

link 1
link 2

Benzotriazole (BTA) is mixed with the deionized (DI) water to a concentration of 1000 parts per million by weight.

8) Molybdate should be added for loops with aluminum and/or steel in them. I don't know how much of a threat steel jet plates pose without molybdate.

9) A study involving the preservation of copper artifacts said BTA must be combined with MTA for the best corrosion prevention.

10) Potassium iodide can enhanced BTA's anti-corrosive action but it must be used in a precise ratio and isn't worth the trouble. Some used iodine in their loops to function as a biocide. It seems too difficult to control the concentration over time to make it worthwhile.

The mixture of 0.1M BTA with 0.01M KI in deionised water increased the efficiency of BTA, whilst in other cases the mixture accelerated corrosion. When a higher concentration of BTA was used, the presence of KI did not cause any significant effect in the process.

11) Silicates are used in some auto antifreezes but might be abrasive and cause sludging. I doubt they're needed in our loops, or desirable.

12) Be careful with OAT/HOAT auto antifreezes if they have 2-EHA, which can rots seals.

13)

Metal oxides are generally not very good conductors, in fact, most are dielectrics and hence non-conductors.

14) Triazole inhibitors inhibit the action of silver, making silver of questionable use when combined with them. The silver's biocidal action would be potentially nullified and the azole would be bound to the silver, nullifying it, too. This seems to be why EK, for instance, says it's super-important to rinse one's loop very thoroughly if one has used some other coolant and why silver coils are bad news.

15)

A conservator's study found that the only solution that stopped corrosion of their copper samples was a combination of benzotriazole (.1M) and AMT (.01M) in ethanol. The water-based version had some corrosion, although that combination was better than BTA alone. They didn't test tolyltriazole nor napthotriazole.

AMT is 2-amino-5-mercapto-1,3,4-thiadiazole

One possible reason for AMT's usefulness in that study is that it's better at removing chloride than BTA. The artifacts contaminated with chloride would have reduced BTA's effectiveness, thus making the addition of AMT helpful. I don't think chloride is going to be an issue in our loops unless people try to use chlorine with silver. It seems clear that the silver coil is a bad idea.

AMT and chloride: link

Most metals, including copper and aluminum, form thin metal oxide film layers when exposed to air for even a brief time -- this is what makes a new penny turn dull after a few days or weeks. These oxide layers are so thin however that for all practical purposes they do not interfere with the conductivity across such layers.

So, you don't want an oxide (corrosion) layer on your block's fins, or anywhere else that's exposed to the fluid. This is where having a thin layer of anti-corrosive, like BTA, comes in. It prevents the oxide layer from forming. However, some oxide layer formation may be unavoidable unless the parts were prepared in an oxygen-free environment and dipped in triazole. Dipping in triazole is apparently a fairly common practice but the protective layer can be worn away if the fluid used by the buyer isn't correct. It should have triazole in it to keep the protective layer renewed.

16) Ethylene glycol would be the better choice, versus propylene, for heat transfer and biocidal action — if not for its toxity. It has a vapor pressure. It should slowly evaporate as far as I know. I have read that even "closed" loops suffer from fluid evaporation so some of the chemicals added to water in coolants may be an inhalation issue. This doesn't merely apply to ethylene glycol. As for glycol, one must ask oneself if anti-freezing is a quality that is important for a room temperature loop.

17) How much is the efficiency of premade PC watercooling coolants negatively impacted by the desire for aesthetic qualities, like dye and UV "reactivity"? Is there a coolant on the market that maximizes both thermal transfer and longevity, while ignoring aesthetics? For instance, opaque coolants can include titanium and/or zinc oxides. These serve no positive function for thermal transfer. Instead, they do the opposite, by replacing water volume.

18) This looks like a typical formulation that will offer good reliability for non-aluminum loops:

Potassium hydroxide, 5–15%
Sodium Molybdate, 5–15%
Benzotriazole, <5%
Borax 5–25%

Accepta 2542 is a high performance molybdate - borate based water treatment corrosion inhibitor scientifically formulated to offer excellent corrosion control for the protection of steel, copper and brass in water systems.

High performance corrosion inhibitor for steel, copper and brass
Minimises unwanted microbiological system growth

Borax is very abrasive, though, so it should always be fully-dissolved in water. The hydroxide and borax are used to elevate/buffer the pH. At low pH, pitting is a problem. At too-high a pH, scaling is a problem.

Note the second attachment which compares corrosion rates between water, uninhibited glycols, and inhibited glycols. Not also how the first one says that glycol is apparently only needed when there is the need for its anti-freeze function.

 

[Eskimonster]

Xtremely god idea. i thought bout it too when i begun with watercooling.
I want to use it in my nxt system.

 

[Grog6]

I've done a bunch of various cooling loops, just not on a computer.
My computer units are sealed, until they fail, then I'll adapt them.

Straight water cools the best.
It's also the most corrosive.

Putting pure lab-grade deionized water into a Clean aluminum system will evolve H2 gas, and eat the aluminum, both overpressurizing the system until it blows, and eating the aluminum, leaving grey powder all thru the system.
I know a guy that destroyed a freshly built Cobra 4.6l car doing just that.
Don't do that, lol.

10% antifreze in with distilled water from the grocery store is good; the AF adds chemicals to keep the various metals from reacting, and will lube any moving parts.
Make sure no salt is added to the water, thus don't use drinkable water, it's full of salt and minerals.

100% AF is not good; glycol is a relatively poor heat conductor to water, almost 3x less efficient.

All antifreezes have some disadvantages:
Ethelene glycol is the Green fluid, it's toxic.
Proplyene Glycol is what's in the computer type fluids, and for swimming pool winterizer kits. It's probably the best alternative.
Methanol/water in a 50/50 ratio is what's in the windshield washer fluid, It's both toxic, and it eats rubber.

More antifreze==less cooling ability, so 10% is what I use in my cars.
I just change it every year, but a jug lasts a long time.

 

[moproblems99]

More antifreze==less cooling ability, so 10% is what I use in my cars.

It is also what keeps it from freezing and splitting heater cores and radiators in places like TN.

 

[Grog6]

Thanks to global warming, it rarely gets that cold here anymore.

 

[Ferrum Master]

Methanol/water in a 50/50 ratio is what's in the windshield washer fluid, It's both toxic, and it eats rubber.

In the EU it is banned, as vapor is also toxic. Isopropyl is used more also plain old ethanol. Any windshield fluid eats rubber, corrodes metal and eats paint, that's actually another story and problem.

 

[Dinnercore]

I use car coolant antifreeze + distilled water in a roughly 20% / 80% solution. I do not maintain my loop for science, I want to see how long I can leave it as is without seeing degrading cooling performance.

The reason I decided to use this is, that its cheap, highly available and tested as working for ages now. The early pioneers in watercooling used this 20 years ago as seen in some very old german forum posts and some have ran this fluid mix 5-10 years untouched without an issue. It´s the blue color stuff, brand called Glysantin here in germany.

Thing is, you really need a certain level of the stuff in your mix, ~20% like mentioned above. I used only 5-10% in a mixture for a test-bench loop and left it sitting in bright sunlight behind a window for 2 months without the loop running and some small patches of mold started growing inside the tubes. Yes I flushed everything beforehand.

 

[dirtyferret]

Why not just hook up one of those mobile AC units to pump cold air into your case?

 

[Grog6]

In the EU it is banned, as vapor is also toxic. Isopropyl is used more also plain old ethanol. Any windshield fluid eats rubber, corrodes metal and eats paint, that's actually another story and problem.

That Sux!

What do people use for Meth injection to cool Blown engines? (Iso doesn't burn the same)
That's the biggest use for it here, lol.

https://www.summitracing.com/parts/sno-201blk?seid=srese1&gclid=EAIaIQobChMItrCFuvq04wIVwp-zCh1gzQRBEAQYASABEgLucfD_BwE

(I'm betting my Street car would get crushed by the police in the EU, lol. No Cats, True 2.5" dual exhaust with no mufflers, extreme cams, lowered suspension with frame stiffening and aftermarket swaybars, Brakes, etc. Heck, I wrote the EEC Tune myself.)

 

[RichF]

Note the second attachment which compares corrosion rates between water, uninhibited glycols, and inhibited glycols. Not also how the first one says that glycol is apparently only needed when there is the need for its anti-freeze function.

That statement is correct when referring to all-copper. However, the inhibited glycol is better when there are other metals involved. If that chart is accurate, if a person is running a 100% copper loop (does anyone even sell copper fittings?) then water is superior to inhibited glycol. For mixed metals, it appears that inhibited glycol is clearly superior.

The problem with that chart, though, is that it uses tap water instead of deionized/distilled. Does anyone have a chart that shows the same data, only without using tap water? Various corporations don't use glycols, by default, in their loops — IBM and Huawei, for example. Huawei uses a "V3" system and a "V5" system. The former uses water and BTA and the latter uses glycol with BTA. The "V" suggests that "V5" is superior but I don't think that's the case, in terms of anything other than perhaps V5 being chilled. That's a guess. If glycol were clearly superior and necessary at regular temperatures, then there is no reason for Huawei to offer a V3 system simultaneously.

I have read several statements from industry sources that suggest that glycol is really only needed when its anti-freeze function is required, although the aforementioned chart also indicates strongly against using water (no glycol) with uninhibited tap water. If the data in that chart is accurate, does it mean that all-copper loops can get by with tap water and a biocide alone?

 

[INSTG8R]

Back when Asetek made and sold their own water cooling gear they shipped it with Redline Water Wetter in a little syringe https://www.redlineoil.com/waterwetter I still use the syringe for “topping up”

 

[Dinnercore]

Note the second attachment which compares corrosion rates between water, uninhibited glycols, and inhibited glycols. Not also how the first one says that glycol is apparently only needed when there is the need for its anti-freeze function.

Interesting data, but what even is 'tap-water'? The quality and contents of tap-water is wildly different across the world.

 

[lexluthermiester]

So today a guy asked me if it's ok to use car coolent in his watercooled system instead of using regular water so he can achieve better temps , i was shocked when i first heard the question , and then i thought that this can actually work , what do you guys think ?

There's no reason you can't. Use a 30/70 Coolant/Distilled Water mix. Depending on where you live, if they have 40/60, just use that. I used to use 50/50 straight out of the bottle from the auto-parts store back in the day. Worked perfectly....

You won't get better temps on ambient water.
Only reason to use antifreeze in your loop is as a biocide or galvanic corrosion inhibitor, unless you plan on sub zero coolant.

....and these are the reasons why.

 

[Grog6]

Worse than not knowing what minerals are in your tap water; if you have a water softener setup, it adds salt to soften the water.

Never use tap water, if you want to know what's really in there.

Distilled water is a minimum for me.

In the US, you can get a copy of the water analysis of your tap water; but it will probably drive you to using bottled water.

 

[RichF]

Interesting data, but what even is 'tap-water'? The quality and contents of tap-water is wildly different across the world.

That data shows, anyway, that unless a person is using an all-copper loop (including only copper fittings, if those even exist), the tap water used for the data isn't adequate. The reason tap water was likely used as the standard for that chart is because it's a large system, one that's too large to make distilled viable, in terms of cost.

Not that I'd recommend it, of course, but if one is to use tap water it seems clear that the addition of AMT is necessary to rid the water of chloride, which BTA isn't good at.

What the chart does strongly suggest, though, is that copper doesn't appear to be particularly vulnerable to corrosion from distilled water. That was the main idea I took from it. However, since mixing metals is all the rage in the DIY market... Also, the dissolved minerals in tap water might also help to protect the copper a bit from dissolved oxygen or contaminants provide some other benefit. It's hard to say since tap water is so variable, especially if it comes from a well.