A better way to tell the temperature of your fermenter

[Feldon]

... What's your opinion best place to read the temp of your wort ?

(In the context of fermenting in a fridge I assume you mean beer, not wort. Wort becomes beer the moment you add yeast).

If you want to know what temp the beer is really fermenting at, then stick a temp probe directly in the beer, about two thirds up from the bottom where active fermentation is mostly taking place (for ale yeast anyway). This is not usually practical so a probe in a thermowell is next best.

Of course you can also attach the temp probe to the outside of the fermentor as many (most?) people do. It can work fine, but be aware that the actual ferm temp inside the vessel is probably a little bit higher during active fermentation than the indicated reading you will get. In practice, if you're making great beer with a probe on the outside keep doing it, just don't fool yourself into thinking you know what temp you are actually fermenting at - you probably don't.

You should also insulate the probe from the air in the fridge by covering it with something. You want to measure the beer temp, not the air temp. Air in the fridge is much more susceptible to wild fluctuations in temp (eg. as soon as you open the fridge door) than the beer which has a much higher thermal mass and will take much longer (hours) to shift in temp in response to being subjected to higher or lower outside air temps.

If you are using one of the new stainless bucket type fermentors or a stainless conical I would think that putting the probe on the outside would be pretty much equivalent to using a thermowell. Metal is much more conductive than plastic. And again, insulate the probe from the fridge air.

 

[Adr_0]

Try this:


there is a 3/8" thermowell - I think from Beerbelly? - with a Keg King controller, CO contact cleaner, a big syringe of heat transfer compound (about 25mL - get from Jaycar), epoxy, and a length of heatshrink.

The Keg King probe is 6mm OD, and the thermowell is 7mm ID so a pretty tight gap.

I just doused the inside with contact cleaner until it poured out, and some gunk came out. That's about the best I could hope for I think.

I used the heatshrink (6mm) to get heat transfer compound all the way to the bottom of the probe. I calculated that 40cm of 0.6cm heatshrink is about 11mL, so I gauged this on the syringe. Once I had hit that, it was very hard to push through so I gently lifted as I pushed, to add about 2mL to the bottom. That should be plenty.

Then, added the probe from the controller in... pushed it down to the bottom and it got nice and squishy. Sweet.

Then just filled up with epoxy with a mixing nozzle. 60min set time, good for 70°C - fine for fermenting.