Homebrewing beer is a hobby that a lot of people take very seriously. It’s almost never about saving money — the equipment and ingredients can get quite expensive. Rather, people like to homebrew their beer because they enjoy the process and take pride in what they’re able to create. Getting the best results is a mix of science and art, and when a homebrewer comes up with a good recipe they want to be able to replicate it accurately. That requires precise measurements and timing, and an automated system can help accomplish that. Redditor Warshi7819 built their own automatic homebrewing system and used a Raspberry Pi to do it.
This system doesn’t automate the entire brewing process, but it does handle some of the more monotonous work. Essentially it automates boiling the wort to prepare it for fermentation. Two 60L kettles are in the setup, and one of the sits higher up than the other. One kettle (for the mash tun) contains the wort that needs to be brought to a boil. The second kettle contains a heating element to boil the water. The second kettle sits higher than the first, so boiling water can be drained by gravity as necessary into the first kettle. A pump can be used to recirculate the water back into the second kettle to maintain the proper temperature.
That entire process is controlled by a Raspberry Pi 3 Model B+. A DS18B20 waterproof temperature sensor sits in each kettle to precisely monitor how hot the water is in each one. The 3200W heating element and Chugger SS inline pump are both turned on when necessary by the Raspberry Pi through solid state relays. That functionality is all controlled by a custom Python script, complete with a user interface created with wxPython. That gives Warshi7819 precise control over the parameters like temperature and boil time, which means they can easily automate that part of the brewing process in order to reproduce recipes time after time.