Thank you...$250 sounds excessive. I can hook up an OLED screen and ESP32 to the senseair and get the same ?
I could even send levels to my home IOT InfluxDB for historical charting.
I could even send levels to my home IOT InfluxDB for historical charting.
most people can't, or more precise they probably can put something together but can't make sure it works correctly under any situation (in operation range)
what you pay for is that someone makes sure it works properly
else you can get sensors with similar or same hardware on amazon too, it's just that their correct reliability is not guaranteed at all and just checking if the values outside seem right is by far not enough to verify that (because it e.g. might behave right on low but not high CO2 levels or not on high/low humidity, etc.)
I have seen tests with sensing devices which seemingly where good outside but then e.g. scaled wrongly being way of at higher CO2 levels (either way higher or way lower).
Perhaps you've left the auto calibration on? That's usually a recipe for disaster (and one that can be avoided by reading the datasheet).
This includes all the sensors integrated in these off the shelf products like the author is using, which could explain the extremely high readings.