From Anton on Hackster.io:
As a Civil Engineer I’m very well aware of how ventilation systems should work at home. So to measure the quality of the air in my apartment I purchased a CO2 monitor and I really liked it because it not only showed CO2 levels but also room temperature.
However, this wasn’t enough for me. I wanted to measure more parameters, so I was looking for an appropriate device. I found some that were ridiculously expensive, so I decided to make my own.
At that time I already had experience programming arduino controllers for a pump station with solenoid valves controlling different pipeline branches.
I made a project on paper and than ordered necessary tools and sensors.
// Read more: original article.

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