Home air monitor is based on the development board NodeMCU (CP2102 version). It includes a temperature sensor - ds18b20, a humidity sensor - HTU21D, a carbon dioxide sensor MNH-Z19. It is also possible to connect one more i2c sensor and a radio module to 433 MHz.
two DS18B20 sensors to D5
Also two sensors with DO directly to D6 and D7.
Spare headers for 3V3 and GND
All pins connected to header for use.
Designed to be used with Double Socket Dual Base Shield for WeMos D1 Mini
PCB is used to control 3 typical CPU fans with mounted high-power LED chips according to temperature and tach sensors
Relays are used to power-off LED drivers in case of fan failure or overtemperature condition