Hello guys! Today I have another great sensor to show you. It is the MH-Z19 CO2 Sensor! I discovered this sensor on Banggood.com a few weeks ago. You can get it here: http://bit.ly/CO2Sensor . The cost of the MH-Z19 CO2 Sensor is around 24$. Banggood.com was kind enough to send me a sample unit in order to test it and build a project with it. It arrived quickly and I am really excited to build something with it!

In my opinion this is a very interesting sensor. Measuring carbon dioxide is important in monitoring indoor air quality. It will be a great addition in our weather station projects.

If the CO2 levels indoors are unsually high, the occupants may get headaches, or to function at lower activity levels. Outdoor CO2 levels are usually 350-450 PPM whereas the maximum indoor CO2 level considered acceptable is 1000 PPM. Humans are the main indoor source of carbon dioxide in most buildings. Indoor CO2 levels are an indicator of the adequacy of outdoor air ventilation relative to indoor occupant density and metabolic activity.

The MH-Z19 CO2 Sensor can be used with an Arduino, a Raspberry Pi, an ESP8266 board or any other microcontroller using the serial interface. It is a 3.3V device but we can use it with an Arduino with 5V logic levels if we just read the output of it.

I am looking forward in using this sensor in a project. I would love to build a simple DIY air quality monitor using the MH-Z19 CO2 Sensor. We can even use an ESP8266 board and upload the Co2 readings on a remote webserver. Also, this sensor is very useful in greenhouse applications where we need to measure the C02 constantly.

Stay tuned, I will prepare a simple project with this sensor soon and I will post a video about it on the YouTube channel!