ESPHome Air Quality Station

ESPHome-powered portable air quality station with HomeAssistant integration

HW parts

Co2 sensor + temperature + humidity

Czech shop (with easy connection by uSup) https://www.laskakit.cz/laskakit-scd41-senzor-co2--teploty-a-vlhkosti-vzduchu/

Better price but long delivery: https://www.aliexpress.com/item/1005006619366785.html

* from aliexpress select correct one

VOX / nOX

Czech shop (with easy connection by uSup): https://www.laskakit.cz/laskakit-sgp41-voc-a-nox-senzor-kvality-ovzdusi/

Better price but long delivery: https://www.aliexpress.com/item/1005006749215421.html

* from aliexpress select correct one

Pressure, temperature, humidity

Czech shop (with easy connection by uSup): https://www.laskakit.cz/arduino-senzor-tlaku--teploty-a-vlhkosti-bme280/

Better price but long delivery: https://www.aliexpress.com/item/1005006995581799.html

* from aliexpress select correct one

ESP32 + display

Czech shop (with easy connection by uSup and battery connection): https://www.laskakit.cz/laskakit-espink-shelf-2-9-esp32-e-paper/

Battery

Czech shop: https://www.laskakit.cz/geb-li-ion-baterie-1x18650-1s1p-3-7v-3200mah/

Cables with connectors

I2C bridge: https://www.laskakit.cz/laskakit-sup-4x-na-dip-adapter/

10cm cable: https://www.laskakit.cz/--sup--stemma-qt--qwiic-jst-sh-4-pin-kabel-10cm/

Battery reduction: https://www.laskakit.cz/jst-ph-2-2mm-do-jst-sh-2-1mm-adapter-pro-baterie--5cm/

3D printed STL files

• body: download
• desk: download
• header: download
• footer: download

Post-production for 3D printed parts

• color in spray: https://www.hornbach.cz/c/barvy-tapety-a-oblozeni-sten/barvy-laky/barvy/barvy-ve-spreji/specialni-efekty-ve-spreji/S12050/

ESPHome config

esp-config.yaml

Interesting

• I couldn't use deep sleep because the VOC sensor needs to collect values continuously
• I used a non-standard I2C - because I needed a perpetual I2C power supply
• I needed to modify the library for ePaper (you can see the link in the code)
• there is an extra sensor for temperature and humidity, because the CO2 sensor generates heat and does not measure properly
• device battery life is about 4 days (without VOC / NOX + deepsleep it would be more than a month)
• the display shows the pressure converted to a specific altitude
• values outside the optimum range are highlighted in black on the display
• if no wifi is available, it stops trying to use it - after reboot (usb-c power connection) it tries to find wifi again