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I came across this image, showing an apparently working motherboard soaked in cooking oil, using the heat from the electronics to deep fry potatoes.

Like most of the internet, the content is of course not trustable. That is why I am asking this question to see if such a thing is at all possible.

I found this question regarding the temperature at which electronics can work, whose answers hint at a maximum of 70C. That doesn't seem true about computers though, as the CPU at least may get even up to 85C and working.

In the image, there is also a thermometer that shows 115, but I can't make out the unit.

So, first of all, can electronics be drenched in oil and still work? If so, is it possible for them to be drowned in oil (which absorbs the heat from the electronics) heated up to such a high degree?

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Shahbaz
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  • It's plausible that electronics (transistors, ICs) can work in cooking oil. Trouble is that the amount of residual moisture in the cooking oil may vary. Temperature limit would depend on the particular components. 115°C is quite hot for electronics, though. – Nick Alexeev Oct 14 '12 at 00:09
  • While this is a moderately interesting question, it's way off topic here, since neither the question nor any possible answers to it would actually help anyone design anything. – Dave Tweed Oct 14 '12 at 00:25
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    @Shahbaz - Take a very close look at the fourth frame of that picture that you linked. The aluminum fry pan is sitting on top of a electric hot plate cooker. My take is that the 80 or 100 watts of power that may nave been coming from the computer board did little to raise the temperature enough to be able to cook the french fries. That heat came from the hot plate. – Michael Karas Oct 14 '12 at 01:16
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    No matter what the answer is, I'd definitely say do NOT eat those french fries. God only knows what kind of chemicals would be absorbed by the cooking oil from the motherboard – Earlz Oct 14 '12 at 02:46
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    Can electronics work drenched in oil? Yes, see http://www.pugetsystems.com/submerged.php But the purpose is to keep the electronics cool. High temperatures will do bad things with or without the oil. – Ben Voigt Oct 14 '12 at 03:07
  • As to the picture itself, I suspect it's fake because A) the bubbles are centered in a spot that's nowhere near any plausible heat source on the motherboard and B) the motherboard is apparently resting directly on a metal pan, which would cause any motherboard I've ever seen to short out. – Random832 Oct 14 '12 at 06:54
  • @DaveTweed, I am aware that it is a bit of a strange question, but I don't believe it to be off topic. First of all, of all the stackexchange websites, this seems to be the only one where you can ask questions whose answers would involve the resistance of oil, working temperature of circuits etc. Another thing is that, knowing electronics are able to resist oil can help greatly if someone is designing electronics for a robot working in dirty environments for example, or as Ben said, to cool off the electronics with oil. – Shahbaz Oct 14 '12 at 12:29
  • @BenVoigt's answer was the first thing I thought of. Some people have tried cooling their motherboards in a "fanless" way doing this. – Rob Oct 14 '12 at 12:36
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    @Random832: When deep frying, the bubbling occurs where the water (in the potatoes) is, not where the heat source is. – Dave Tweed Oct 14 '12 at 12:43
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    If you do this, don't eat the potatoes. – Chris Stratton Oct 15 '12 at 03:31

1 Answers1

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Instead of guessing, read the datasheet. Silicon stops being a semiconductor at around 150°C, so that is a upper limit. However, it still has to do useful stuff, so the practical limit is lower. 70°C is a common "consumer" grade upper limit. "Industrial" grade devices will go higher, usually around 120°C. Military grade can go higher. Of course all this comes at a cost premium.

There are other electronic devices than just silicon semiconductors, and some of them can be significantly less tolerant. Look at the datasheet for a electrolytic cap, for example. Not only will you probably see a low max operating temperature, but you will notice that lifetime is severely degraded at that temperature.

As for the oil, as long as it is water free and insulating, most electronics will probably be OK with it, at least for a while. Some seals on electrolytic capacitors are known to swell up and become useless in mineral oil, so cooking oil probably isn't much better. I'd worry about the cooking oil degrading into other chemicals over time or due to bacterial action, and those chemicals causing problems, like shorts, corrosion, electrolysis, etc.

Chris Laplante
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Olin Lathrop
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    Also, note that solder melts at about 180 C to 220C typically, and deep frying goes above 190 C, so you may loosen components if if frying properly. – Juancho Oct 14 '12 at 00:24
  • I had very much suspected that the image is fake, but I had to ask because I'm not so experienced when it comes to electronics. Thanks for your answer. – Shahbaz Oct 14 '12 at 12:32
  • Another problem is that oil absorbs water over time. Oil filled electrical equipment (i.e. transformers) must either be hermetically sealed, or include an air-breather filled with silica gel dessiccant. – Li-aung Yip Apr 14 '15 at 04:19