Originally Posted by Gipper
Have the same situation as the OP. My first batch (Kolsch) is currently fermenting at 78 degrees. My basement isn't as cool as I thought and the recent heat wave isn't helping! I have an extra fridge and was considering buying the Johnson Controls temperature controller so I can ferment at or below 70 degrees, but was wondering if anyone thinks these devices will cause damage to the fridge? It's essentially like plugging and unplugging the fridge many times per day, which cannot possibly be good for the fridge components long term?
Refrigerator compressors turn on and off via a relay just like in the Johnson controller, not sure about the other electronics, which is a valid concern.
I have a johnson controller but replaced it with a control products controller, http://www.amazon.com/Control-Products-TC-9102D-HV-Temperature-Controller/dp/B0057APR3I
I think you can find them cheaper, but they are dual stage, so they will control a heat source and a cold source at the same time, plus the red LED makes it easy to read, especially in a dark basement.
To change the Johnson controller from heating to cooling you must open the case and phsically move a jumper. The control products controller does it all with software/firmware. No jumpers, it's all in the programmable menu.