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Thermowell Oil?

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sandyeggoxj

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I have some stout tanks and the thermowells are welded into place and polished on the inside with 1/2"NPT on the outside. My BCS temp probes thread into the pipe thread but there is an air gap between the temp sensor and the liquid.

I've done some reading and this is a poor setup since air insulates. I was thinking about using some food-grade mineral oil, like this http://www.amazon.com/dp/B001ESTA30/?tag=skimlinks_replacement-20, so that the temp probe makes full liquid contact. A little teflon tape on the threads and it should stay sealed forever.

Is there a better way? There is enough air that I would probably need an ounce of thermal paste to get good contact and that isn't the best heat conductor when it is applied real thick. In hindsight I should have ordered a 1.5" TC there instead and used a triclamp temp probe.
 
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I'm not sure about this, but would mineral oil expand under heat? That might cause some pressure within the thermo well? Also, what makes you say that thermal compound is not a great heat conducter when applied in quantity? I know in a computer processor/microchip heat sink scenario that's true, but only because applying it too thick, can cause the heat sink to not mate correctly, and cause a air gap that will super heat. But in a thermo well, I'm sure this is not the case.
 
I'm sure there is some brewing based store in the states that will have the right amount you need. I guess the electric brewing section might have some leads. That or other alternatives. I have seen guys in the diy threads also use industrial use thermo compound.
 
I have the same basic setup as you (stout tanks w/ temp sensor in one of the thermowells). I don't know what the best thing to use is, but I used this:

http://www.omega.com/pptst/OT-201.html

It seems to be working well, the temperature changes reflect pretty quickly.

I ended up buying way too much so if you want I could send you enough for your thermowells and you could give it a try.
 
We use peanut oil. Just in case it gets in the process it won't be an incident. We had mineral oil get in a tank one time. It wasn't pleasant.
 
I know you don't want to buy new temp sensors but I had Auber make a custom temp probe sensor setup that had an exposed sensor tip and was attached to 1/2" MPT so that I could secure the sensor in my Stout kettles. Here's a link to the product they now offer.

http://www.auberins.com/index.php?main_page=product_info&cPath=20_15&products_id=46

I had them cut down the cabling to 3" so that the tip (with thermal grease) makes contact with the end of the well.

I can't speak for the responsiveness of the system as I am still waiting on my replacement in-line fan to finally brew.

In hindsight, I agree that a TC for a temp probe would have been best
 
I have the same basic setup as you (stout tanks w/ temp sensor in one of the thermowells). I don't know what the best thing to use is, but I used this:

http://www.omega.com/pptst/OT-201.html

It seems to be working well, the temperature changes reflect pretty quickly.

I ended up buying way too much so if you want I could send you enough for your thermowells and you could give it a try.

This is exactly what I was looking for! I would love to get some of that. Can I send you some $$ in return? I have three thermowells that would need to be filled. Mostly just the last inch or so. Enough so that the end of the probe is immersed in the paste which touches the end of the thermowell.
 
No need to send any money, glad I can help out. Just let me know where to send it and I'll drop some in the mail.
 
@highbank,

The magic goo showed up today. Awesome! I'll get it installed in the next few days. Planning to brew on Monday or Tuesday. I'll report back with how well it worked.

On a side note, why don't places like brewers hardware, ebrewsupply and stout kettles sell this stuff? Stout kettles makes my kettles and they didn't have anything to say about this. They recommended citrus oil or mineral oil. But in an enclosed space I can't see it working out well.
 
@highbank,

The magic goo showed up today. Awesome! I'll get it installed in the next few days. Planning to brew on Monday or Tuesday. I'll report back with how well it worked.

On a side note, why don't places like brewers hardware, ebrewsupply and stout kettles sell this stuff? Stout kettles makes my kettles and they didn't have anything to say about this. They recommended citrus oil or mineral oil. But in an enclosed space I can't see it working out well.

Awesome! Nice one highbank. And sandy, can't wait to hear your results. The only place that makes brew specific pots in South Africa, the thermometers they provide have a study probe and screw directly on the pot, so no need for a thermowell. We have guys that resell blichmann and braumeister equipment as well from the USA, but none of them sell thermal compound either...
 
I attempted to install the compound. I need to devise a better way to get it into the thermowell. It is very tacky and hard to press into the thermowell. It did help out. My temperature were more responsive and more accurate. I was having problems with my mash not reflecting the actual temperature. Now when I manually probe the mash bed with a calibrated digital I get readings within a degree of my BCS.
 
Thermal compound is best. However, I use a food grade lubricant (keg lube). Put small amounts in a drinking straw, insert in the thermowell, and blow it in. Works great!
 
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