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ESP32 used to control a decentralized Fan with Heat Recovery functionality based on several sensors via MQTT
The ESP32 – programmed via ARDUINO environment – reads the values of three Humidity/Temp. Sensors (SHT22) inside, inside @the outside wall (for calculating the dew point) and outside to control a SUEDWIND Ambientika SOLO (dezentrale Wohnraumlüftung mit Wärmerückgewinnung (93%) , 160 mm, 60m³/h @~300€ via Amazon).
One relay switches on/off the Fan, another one the speed of the very quiet BLDC Motor used in the above SÜDWIND Fan.
The S/W is ready and based on either BASECAMP (CT Project) or standard WiFi libraries including MQTT support to visualize the measured values via a MQTT Mosquitto and FHEM based Raspberry Pi (see attached graphs).
Furthermore FHEM allows to control the Motor (on/off and speed) remotely from anywhere if necessary.
A Fritzing based PCB is available as well, incuding additionally connector to an OLED Display and also (via Mosfets) to RGBW-LED Stripe (4 channel) to create some nice lighting athmosphere in the bathroom.