My winter fermentation challenge is that the fridge I have available for fermenting won’t maintain a high enough temperature, particularly at night, even with a Johnson controller. The room it’s in doesn’t go to freezing, but it is cold enough that the fridge never makes it past the high 50s. I use 5-gallon buckets for 3-gallon batches and have a Danby no-freezer small fridge. Am I correct that I’d plug the fridge into the wall for normal operation, plug the heat source into the controller, and put the heat source on the inside wall of the fridge, with the probe taped as usual to the fermenter with a little styrofoam or other padding over the probe?
Why would you plug the fridge in to the wall? Single stage (heat only) should do well, but a dual stage controller might be better.
When I lived in Dallas, my ferm freezer was in the garage and it often dipped to below 30 in the winter. Though I had a dual stage, I only operated one at a time depending on the need.
I used the heating pad method as well. It’s a pretty funny setup. The heating pad shuts off after an hour, so I have the pad plugged into a timer that runs the heating pad for 55 minutes every two hours.
Ideally, in your situation you’d probably want to run a 2-stage controller with both the fridge and heater plugged into it.
They aren’t horribly expense, and Auber is actually having a sale right now:
If using a single stage controller, I think you’d want to unplug the fridge and have the heater plugged into the controller. I did the opposite for a long time, and it worked well.
I have a Fermwrap plugged into the Johnson A419, the heater is taped to the wall of the freezer but the freezer is not plugged in. The probe is attached under bubble wrap and taped to the side of the fermenter.
Inkbird dual stage controllers have been on sale on amazon for less than $30 for the last month. They heat and cooler and are rated to run most fridges and a heat pad. You could probably find a heat pad at CVS on sale for under 20.