Martin’s DIY Internet connected smart humidifier project:
The project uses a DHT22 temperature sensor mounted to the side of the enclosure for better ventilation and reliable reading:
I threw in a ultra-cheap I2C OLED status display to get a visual reading. Milling the box so that the OLED shows was pretty nasty, hated it. I cut a piece of paper and placed it on top of the cover, below the transparent lid to cover up for the lousy milling job
The humidistat switches on and off the humidifier as needed, the humidifier itself is plugged in to a plug in the relay. The humidifier auto detects when water is out and stops, so I didn’t have to care about that.
Source code for the project is available on GitHub.
Project info at Martin Harizanov’s site.