Distilled vs Purified Drinking Water

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I recently drained the radiator in my car and refilled with some 100% HOAT coolant (G-05) and Purified Drinking Water. It didn't occur to me at the time, but what I have used in the past was always Distilled Water (gallon jugs of Walmart's house brand). But it's starting to creep into my head as a possible liability. Anyone ever had issues with using purified drinking water versus the distilled kind? Maybe I'm making a mountain out of a mole-hill, but my car's engine cooling system is pretty important, given my geographic location and the intense summers I put it through. So if there's going to be a problem later on the down the road from using the purified drinking kind of water, I'd rather just drain the whole system and refill with distilled now while I have the luxury of deciding when/where to do such a task.
 
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Distilled would be the correct one to use. However, there are some people who insist that Drinking Water is the correct one to use, but they can never provide a scientific answer.
 

The_Nuke

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Yes, distilled is always better, I get that. In hindsight, i should have noticed i grabbed the wrong kind, but what's done is done. I was wondering if the purified water, while not as god as distilled, could still be good enough. The answer to that is much more nebulous it seems though, so if I want to err on the side of caution, I'll need to do another drain and fill i guess. Oh well, at least it's not 125F in the garage like it is during summer. Maybe this D&F will be a little easier to get done without stroking out half-way thru...which remind me, I still need to figure out a way to out an a/c unit in there before next summer. That would make life truly worth living for me! Thanks for the quick replies, Nuke
 
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Distilled water is optimal but realistically you will likely never see a difference. Distilled water is, in theory, pure H20, while "Drinking water" probably came out of a municipal source, was filtered, and may have had additional minerals added back for taste. Our GMs spec "clean, drinkable water" in the owners' manual for mixing with the full-strength coolant. So you should be fine. I wouldn't worry. Many people just use water out of the hose.
 
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I just went through this yesterday, as distilled water is kind of hard to find locally for some reason. Lots of purified water though. To make the plot even more interesting, a few gallons of purified water had "Purified via deionization and distillation" So... Perhaps some purified water is even more "pure" than distilled?
 
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The "drinking" water is most likely purified via reverse osmosis. I have an R/O system and that's the only water I use for such purposes. The total dissolved solids is VERY low. There is very little added to the drinking water to make it taste less flat. I would not worry about it at all.
 
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Even though I have multiple filters and an R.O. unit I still use distilled water to make sure it's as pure as possible or buy the pre-mix stuff if it's a reasonable price.
 

The_Nuke

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Originally Posted By: fields
Go with it. You will be fine.
You don't happen to work in a shop that sells or services radiators do you?? I'll go ahead and put a mark in the "Leave It" column of the "Change It/Leave It" spreadsheet I've got to tally votes on the topic, but I'm afraid I will need to see some documentation about current employment to make sure you aren't just trying to drum up some future business laugh
 

The_Nuke

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Originally Posted By: DBMaster
The "drinking" water is most likely purified via reverse osmosis. I have an R/O system and that's the only water I use for such purposes. The total dissolved solids is VERY low. There is very little added to the drinking water to make it taste less flat. I would not worry about it at all.
It could be, but given that I did not buy the premium brand or anything, I would not be surprised if it was actually one of those deals where they just pay some city for their municipal water and resell it without doing anything to it one way or the other. That would be the worst case scenario, sure, but luckily I will not have to worry about it and can actually rest easy now (see next post).
 
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Most people don't even change their coolant until something fails in their cooling system. We all need to remember that by simply changing our coolant, we're probably in the top 5-10% of car owners in terms of maintenance. The same thing applies when have thread after thread full of hand-wringing over when to change our gear oil. Most vehicles probably go to the junkyard with the original gear oil.
 
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Originally Posted By: The_Nuke
Originally Posted By: DBMaster
The "drinking" water is most likely purified via reverse osmosis. I have an R/O system and that's the only water I use for such purposes. The total dissolved solids is VERY low. There is very little added to the drinking water to make it taste less flat. I would not worry about it at all.
It could be, but given that I did not buy the premium brand or anything, I would not be surprised if it was actually one of those deals where they just pay some city for their municipal water and resell it without doing anything to it one way or the other. That would be the worst case scenario, sure, but luckily I will not have to worry about it and can actually rest easy now (see next post).
I would be EXTREMELY surprised if the water was not ultra filtered or treated with reverse osmosis. I think far too much emphasis has been placed on the water used to mix coolant.
 

The_Nuke

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Okay, the threat has passed, and we can all breath a collective sigh of relief! I am please to announce that, after some digging through my notes from the previous maintenance that necessitated the coolant & water replacement, it turns out that the G-05 + water mix I used was indeed mixed with distilled water. Woo-Hoo!! Once I read my notes and realized the coolant/water I added was already mixed, it dawned on me that the purified drinking water I bought never got used (for the car's coolant anyway). I had mixed what was left of some 100% G-05 with what was left of the distilled water after the coolant replacement I did last year, and it's been sitting on the shelf ever since. Not remembering the water was already in it, I grabbed some that day (the purified drinking water) to mix with it before draining old coolant and working on car that night. But then I re-remembered the water was already in the coolant and that I didn't need to add any more water. Which meant the purified stuff was set aside for something else (IIRC I used it while washing the car later a few days later). Confusing? I would imagine, and I am sorry for that.. Convoluted? Sure, but that's just how my life usually plays out... The absolute truth? Yep, and I've got documentation to back me up... Possible early onset Alzheimer's? I certainly hope not, but my misspent youth and decadent middle ages surely did some damage to the ole noodle, so anything's possible...which is why you should always make notes when you work on your car! This is a perfect example!! Now the only question becomes what do I do with the extra money and time I find myself with since I will not be buying any expensive engine coolant and rolling around under my car doing a D&F...I know, I'll hit the store and get me some Nolan Ryan top sirloins and a couple of beers and do some grilling and drinking (followed by eating!) with that time and money. Thanks again to everyone for the quick responses, Nuke
 
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Good job here keeping your notes. Very smart indeed. I could be wrong but some have said that the minerals in water was more of a problem in Europe than here in the US. I would say that is likely not true due to the fact that mineral elements are present in certain areas of the this country has well. I know sulfur had to have been in our water in one area where my parents had a house. The water smelled liked old eggs when it came out of the tap. Having said that, you did really well documenting your information about your car maintenance. Great deal there. If you ever decided to sell the vehicle then the next owner would be very lucky that you had it before them. And in the spirit of documenting things.. I apologise for my msg to you that time awhile back. I really mishandled that in how I stated things in it. It was very poor form and was not done in a right or good way. I am sorry for not doing that in a different and better way.
 
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Originally Posted By: Dumc87
I just went through this yesterday, as distilled water is kind of hard to find locally for some reason. Lots of purified water though. To make the plot even more interesting, a few gallons of purified water had "Purified via deionization and distillation" So... Perhaps some purified water is even more "pure" than distilled?
Distilled water is a type or purified water. Purified water can be made by various processes such as deionization, distillation, ion exchange, reverse osmosis, or filtration. How do you define "pure". Does pure mean free from ions, endotoxins, microbial, chemical or other contaminants? Any purified water is fine for a radiator.
 
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Distilled water has no mineral value, and why its not idea water to drink, but great for cooling systems. Bottled drinking water is not a substitute , unless an emergency.
 
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Originally Posted By: Reddy45
Distilled would be the correct one to use. However, there are some people who insist that Drinking Water is the correct one to use, but they can never provide a scientific answer.
I've seen it argued that distilled water is more likely to cause corrosion, since it has nothing in it and therefore is more likely to leach metal ions. Makes some sense but on balance I don't think I buy it. OTOH I'm not paying to put distilled water in a radiator. I use aircon condensate after flushing first with tap water and then with water from a campus drinking water dispenser. These usually have filters, ion-exchange resins, and activated charcoal cannisters in them (hopefully replaced occaisionally) though some are reverse osmosis.
 
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