A419 Temp probe location in Chest Freezer?

I've read through a number of threads, and am still a little confused about where the best place is to locate my temp probe for my chest freezer fermentation chamber. I'm controlling it with a Johnson A419.

I'm thinking about taping it to the side of the fermentation bucket - with some sort of insulation to keep it away from the ambient air. Is there a better way to do this?

Bump. Any thoughts on this? Much appreciated.

Get a thermowell from Brewers Hardware and control the actual fermentation temps instead of guessing.

alexavery said:

I've read through a number of threads, and am still a little confused about where the best place is to locate my temp probe for my chest freezer fermentation chamber. I'm controlling it with a Johnson A419.

I'm thinking about taping it to the side of the fermentation bucket - with some sort of insulation to keep it away from the ambient air. Is there a better way to do this?

Click to expand...

Here's what works for me:
https://www.homebrewtalk.com/f11/johnson-a419-freezer-thermowell-help-123238/#post1404063

Everyone has a different opinion on this subject. After doing it several ways I have a thermowell inside my fermenting keg as well as a thermo taped on the outside. The temperature difference is a few degrees so I adjust my controller accordingly. An automatic system to average the two temps would be ideal for me.

I am planning on putting my probe into a jar full of some kind of medium, fine sand or some kind of inert gel. I'll have a fan in the keezer, so I expect the air temp will be relatively consistent throughout.

Gremlyn1, how did you wire the fan for the freezer? Is it on all the time?

I installed a fan and run it continuously. I have the controller probe positioned in the air stream of the fan. I use a separate digital thermometer with it's probe attached to the side of a keg and covered with a small square of bubble foil insulation. The controller is set to a 4 deg differential. The keg temperatures are very stable +/- 1 deg or less even with this wide differential setting.

FYI, I recently added 3/4" insulation to the collar. The energy consumption dropped by at least 40% with this improvement. Possibly even more than that. I will check it again to verify, but it appears that the insulation made a dramatic difference. Running the fan continuously without the insulated collar was using about 1 kwh per day. Almost cut that in half. I do not think the difference would have been that large without a fan.