Environmental Sensor

A WiFi environmental sensor based on Tasmota that reports temperature, air pressure, air quality, humidity and CO2 (ppm).

Description

It features the following sensors:

• BME 280 / BME 680 - air pressure, air quality (BME 680) and humidity
• MH-Z19B - CO2 (ppm)
• DS18B20 - temperature

The DS18B20 is featured on the PCB because the temperature sensor of the BME 280 / BME 680 is very sensitive - simply holding your finger above it may cause incorrect readings. The DS18B20 is reasonably accurate, cheap and known in the DIY community, so it was a simple addition to get reliable temperature readings.

Either a BME 280 or a BME 680 is supported by the PCB. This was only added because I had a BME 680 lying around, so why not use it - the BME 280 is cheaper and due to the MH-Z19B the air quality reading is pretty obsolete, so in general I recommend installing a BME 280.

The PCB has an internal cutout to avoid transferring heat from the D1 Mini to the temperature-reading components on the other side.

The software intended to be run on the device is Tasmota. A preconfigured template will be added later.

Parts list

• D1 Mini
• BME 280 breakout board
• DS18B20
• MH-Z19B

Attributions

MH-Z19B footprint (MIT) by Matthias Kleine (klein0r)