I am probably flattering myself, taking any sort of credit for inspiring this sweet custom temperature controller built by Adafruit reader Mike to keep his beer-brewing fridge at a constant temperature. Like my recent project, it simultaneously controls AC-powered heating and cooling equipment to maintain a constant temperature, and is mounted in a hardware-store PVC junction box. But there the similarities pretty much end. Whereas I used a cheap off-the-shelf thermostat module from China, Mike built and programmed his own controller using an Arduino for brains, an Xbee for remote temperature control and data logging, and a cool multicolor LED display with letters that turn red when the system is heating, blue when it is cooling, and green when it is at the correct temperature. [Thanks, Tom!]

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