From the Lytron website. - Snip - Care must be exercised when using DI water. The very lack of ions also makes this coolant unusually corrosive. Called the "universal solvent," DI water is one of the most aggressive solvents known. In fact, to a varying degree, it will dissolve everything to which it is exposed. Therefore, all materials in the cooling loop must be corrosion-resistant. - Snip - http://www.lytron.com/support/di.htm
Distilled is not deionized, and deionized water only stays deionized if it's not in contact with any metals or air. I agree it's non conductive, but only until it touches any metal. I've seen it dissolve the solder on PCB's.
Actually I used to use Shell DialaAX in the laser power supplies I used to build. It is mineral oil based, but it has stablizers in it that makes it last and not oxidize.
The best (but most expensive) solution is 3M Flourinert. We use FC-77 at my place of business. But it's $350 for 11 lbs. (about 3/4 of a gallon).
Oil comes with some problems. It is more viscous (thicker) than FC-77, so it won't circulate or flow as well, it's a lot less dense and has a lot lower specific heat. This means that it won't cool as well.
It's also a huge mess. Everything gets covered in it. It will slowly leach through even the tiniest of cracks. Any oil that collects on the ouside of the case will attract dust and dirt. It attacks many plastic and rubber materials including most silicone sealants. I remember it causing one type of shrink tubing to expand to about 2 times it's length. Some capacitors unwrapped themselves, and I've known some people to be mildly allergic to it.
FC-77 on the other hand is beautiful to work with, (other than the cost). It's water clear, when you remove the electronics from the tank, the FC-77 evaporates away in a few minutes leaving absoultly no residue. It boils at 97 deg C. So if you have a really hot part, the boiling (phase change) takes away even more heat. It attacks almost nothing (inert). Won't stain, or mess up your carpet and is practically non-toxic. You do need to protect it from evaporation though.
Just a note on De-ionized water, anyone who ever worked with it knows it's very corrosive. It tries to bond with ions in anything it can get it's hands on. It dosn't stay deionized for very long if it's in contact with any metals.
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From the Lytron website.
- Snip -
Care must be exercised when using DI water. The very lack of ions also makes this coolant unusually corrosive. Called the "universal solvent," DI water is one of the most aggressive solvents known. In fact, to a varying degree, it will dissolve everything to which it is exposed. Therefore, all materials in the cooling loop must be corrosion-resistant.
- Snip -
http://www.lytron.com/support/di.htm
Distilled is not deionized, and deionized water only stays deionized if it's not in contact with any metals or air. I agree it's non conductive, but only until it touches any metal. I've seen it dissolve the solder on PCB's.
Actually I used to use Shell DialaAX in the laser power supplies I used to build. It is mineral oil based, but it has stablizers in it that makes it last and not oxidize. The best (but most expensive) solution is 3M Flourinert. We use FC-77 at my place of business. But it's $350 for 11 lbs. (about 3/4 of a gallon).
Oil comes with some problems. It is more viscous (thicker) than FC-77, so it won't circulate or flow as well, it's a lot less dense and has a lot lower specific heat. This means that it won't cool as well.
It's also a huge mess. Everything gets covered in it. It will slowly leach through even the tiniest of cracks. Any oil that collects on the ouside of the case will attract dust and dirt. It attacks many plastic and rubber materials including most silicone sealants. I remember it causing one type of shrink tubing to expand to about 2 times it's length. Some capacitors unwrapped themselves, and I've known some people to be mildly allergic to it.
FC-77 on the other hand is beautiful to work with, (other than the cost). It's water clear, when you remove the electronics from the tank, the FC-77 evaporates away in a few minutes leaving absoultly no residue. It boils at 97 deg C. So if you have a really hot part, the boiling (phase change) takes away even more heat. It attacks almost nothing (inert). Won't stain, or mess up your carpet and is practically non-toxic. You do need to protect it from evaporation though.
Just a note on De-ionized water, anyone who ever worked with it knows it's very corrosive. It tries to bond with ions in anything it can get it's hands on. It dosn't stay deionized for very long if it's in contact with any metals.