Hello I just bought a used refrigerator for fermenting beer. Well I am using water in my fermenter to test it out with my dual temperature controller well my question is I had my controller set to 68f last night an it hold that temp but before I went to bed last night I set my controller to 70f but got up an I see my controller is at 65f. So basically what I am asking do I need to apply anying heating to get it up too the 70f the controller I am using is dual ranco temperature controller. An also I forgot to mention that my probe is in a Thermowell.
If the room you’re in is below 70*, then yes… There are many ways to do that, light bulb, heating mat wrapped around your fermenter, milk house sort of heater… The temp probe also should be addressed… Some tape it to the fermenter… I put mine in a tube of aloe vera, as I couldn’t find glycerin gelatin… The other piece to ponder too, is the fermenter temp will rise due to heat created during fermenting (there is a fancy word for that)… I set my controller to about 63*… after primary fermenting is done, perhaps 3 days with ales, then I let it rise to room temp to “finish up” its process… Sneezles61
Another thing to keep in mind is that the refrigerator will get much colder than your controller setpoint. Set the refrigerator’s control to minimum cooling. That might be around 40 degrees. Say you set your controller to 60 with a 2 degree hysteresis. When the wort reaches 62, the refrigerator will turn on. The air in the frig cools much faster than the wort, limited only the frig controller. By the time your wort gets down to 60, the air in the frig might be 40, so the wort will continue to cool after the controller turns the frig off, until the air heats up.
I don’t use a refrigerator for fermenting but I use a chest freezer for my keezer, I place the temp probe in a bottle of water to keep the controller more constant. I tried just dangling in the chest freezer when I first got it but the temp swings were very radical and that can be hard on the freezer compresser turning on and off constantly. The light bulb seems like a good idea and maybe try taping the probe to your fermenter.
I ferment in my 10 cu ft chest freezer. I have the little inkbird controller and put the temp sensor in a smaller plastic ( empty vitamin) container that I drilled a small hole in the cap that allows the sensor to be held snug in the center of the water. At the same time the freezer is plugged into the cooling outlet on the controller and I bought a little 15.00 ceramic cube heater that is plugged into the heat outlet on the controller.
I don’t log the temperature performance but any Time I check, my fermentor and probe water are right within the set point hysteresis. I once tried a digital thermometer that would latch the highest and lowest temp but it was a cheapie and could not handle the humidity.
I do have to set it cooler on the beginning of the fermentation ( found that out the hard way) as it builds up heat with the yeast in high gear. I am still trying to come up with that k factor to use… I think I need to be more patient and pitch my yeast at the lower end of the temp range so I don’t have to try to catch up to it. 5 gal is still quite a mass to heat and cool.