Dr. Fermentor V9 - Cooling and Heating Fermentation by an Arduino Controller

I built a system to control the fermentation temperature of my brew (beer, wine, whisky) by circulating hot or cold water through the fermentation vessel by means of a heat exchanger (a stainless steel wort chiller) which is located inside the fermentation vessel. The temperature is controlled by an Arduino controller, which controls (1) the heating elements of an electric kettle (2) a compressor’s cooling coils that were retrofitted into the electric kettle and (3) a pump also located inside the kettle. Digital thermometers signal the arduino which activates the kettle, compressor and pump via a Relay Switch therefore allowing for full temperature control of your fermentor. The aim was to build a system that can control the temperature on a large fermentor that will not fit inside a refrigerator. Here, I demonstrate fermentation with a standard 23 liter plastic bucket fermenter but I plan to use my 70 liter brew pot in the future as the fermentor (the wort chiller will be retrofitted into the lid and silicon tubing will be used as a gasket clamped down with locking pliers).”

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