AirQuality V3

What is the AirQuality V3?

The AirQuality V3 is an air quality sensor made from scratch. I wanted a cheaper sensor than the commercially available options, but more capabilities than the open-source options AirGradient.
It also gave me a good project to continue on my journey to learn more on developing electronics and embedded software.

The sensor periodically polls the sensors (as per the datasheets) and publishes the new values to a MQTT topic. Home Assistant is then able to pick up the values automatically trough auto-discovery.
OTA updates and configuration is supported trough a web interface.

This repository houses the source code, BOM, for the AirQuality V3 and the KiCad files.


Cost for all components for a single board is about $53. Most expensive components are the PMS5003 ($17), SenseAir S8 ($18), the SGP41 gas sensor ($7) and the ESP32-S3 ($4.7). The 4-layer PCB itself strongely depends on how many you order, but is around $4 per PCB, brining the total cost per Air Quality sensor to $57.


- NOx and VOC gas sensing - Sensirion SGP41 sensor
- Temperature, Humidity and Pressure sensor - Bosch BME280
- CO2 - SenseAir S8
- Ambient Light - Vishay VEML7700
- PM1.0, PM2.5 and PM10.0 particle concentration Particle - PMS5003

For more info, check the GitHub page.