Thermowells 101

[W0rter]

Hi, I recently bought a Stout Tanks & Kettles 7.3 Gal Shorty Fermenter with a thermowell. I've never seen a thermowell until this was delivered. It's a SS sheath that encircles the mechanical probe from the thermometer. So the beer never comes in contact with the probe. I asked John about the well and I don't remember the complete conversation. I think he said to put some kind of substance in the well to take up the air space so it'll read as if it were actually in the beer. What would you suggest to put in the thermowell? Should I change the substance every batch? do I leave the thermometer in the well always, I just don't have any idea what to do with this well to ensure I get accurate readings for my temps. Are all thermowells like this? even in kettles from like Blichmann?

Thanks, planning a Belgium Ale for tomorrow.

 

[FuzzeWuzze]

Ive never heard of anybody putting anything inside of them...your thermometer is going to be resting on the metal inside the thermowell taking a measurement anyways...

 

[W0rter]

OK, tomorrow I'll try without and see. Sure won't hurt. Thanks

 

[Adeering]

Sorry to bring up an old thread, but I just got my tanks and was looking for the name of the stuff to get (cause I accidently threw away the info that came with it) but its a thermal paste or silicone. You will want to use it and leave the temp probe in the well. As the way it is mounted it might not have solid contact with the metal walls. This way you get a complete and conductive contact and reduce the lag in temp readings.

I believe you can find the stuff at Radio Shack for sure and possibly Home Depot/Lowes

 

[W0rter]

Hi Adeering,
I contacted John @ Stout Tanks & Kettles and proposed this question, "Please shed some light on what could be used and where it could possibly be acquired. I don't think Thermo paste that is used under a computer CPU would be a good choice. and how often should it be changed or cleaned?"

This is a direct quote from John,

That stuff will work. You can also use mineral oil or citrus oil. If you use mineral oil, you would need to use Teflon tape when you thread in the thermometer. I think it could stay sealed up for perpetuity. In my brewery, we never messed with the citrus oil unless we had to replace the probe (we use electronic probes) and too much came out with the old one.

So I like the mineral oil idea best as it could be cleaned up better than thermal paste. I liked his electronic probe idea also. I have a Liquid tight "K type", 4" probe, 1/2 NPT Thread, Item #: TC-K100M1/2NPT from Aubrins and also have a SYL-2362 PID laying around with a small control panel. I never did like stooping down to check the temps on my conical so I'm going to setup the electronic probe/PID to facilitate that and may even devise a way to control the conical fermenting temperatures. Electric pipe wraps come to mind which would allow me to ferment in the winter in my garage and finally brew some lagers.

 

[helibrewer]

I use mineral oil for cutting boards in my thermowells

 

[matt3]

As long as the end of the thermocouple is touching the back of the well, your good to go. No need to fill the well with any substance because the actual reading is taken at the end of the thermocouple at the point where the two pieces of metal in the thermocouple touch.