Airsensor

This Arduino project implements an indoor air quality sensor based on the ESP8266.

Components

• NodeMCU 1.0 (ESP-12E)
• MH-Z19 or MH-Z18 CO2 sensor
• Bosch BME280 sensor (I²C) for temperature, humidity and pressure
• SSD1306 OLED display (I²C)

Data transmission

The sensor data can be recorded via:

• MQTT
• InfluxDB

Pins

Connect the components to the following pins:

• MH-Z19 or MH-Z18:
  • D7 (GPIO13) as RXD2
  • D8 (GPIO15) as TXD2
• BME280 and SSD1306:
  • D3 (GPIO0) as SDA for I²C
  • D4 (GPIO2) as SDC for I²C