A friend of mine is a scientist who does experiments that are very sensitive to air temperature and humidity. The incubator room has a small ceramic heater but the heater’s thermostat was not nearly accurate enough, only able to maintain the temperature within 10-15 degrees.
Commercial devices that log temperature and humidity can be quite expensive, and getting the data from the device can be difficult. Plus, they can’t control the temperature, only log the data. He asked how hard would it be to build a device that could accurately control the heater through a relay while logging the temperature and humidity. Sounded easy enough.
Grabbing an ESP8266, relay, DHT22, and some online IoT platform, we’re off.”

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