CozIR®-A 10,000 ppm CO2 Sensor

Works very well. Seems to agree fairly closely with another standalone sensor. I am looking forward to playing with it more.

A couple of quibbles:
1. I wanted to use it on a Mac; however, the GasLab software apparently does not run native on MacOS, requiring the hassle of setting up a virtual machine. Not a big problem for me, I copied and ran the Python program found in the app note AN127.
2. in order to determine the serial device used, there is a simple old trick: list the /dev directory before and after plugging the sensor in, save the listing to files, and diff the files. On Mac you will then find 2 serial devices, /dev/tty.usbserial-XXXXXX and /dev/cu.usbserial-XXXXXX. I am using the "cu" device but I understand either will work.
2. this Python program is a good start but my sensor always responds to the 3rd poll request with " M ?\r\n". This crashes the program because it can't convert that to a float. I revised the program to use readline() and throw the returned data away unless it starts with " Z ".

I got the CozIR with the USB dongle. It works well - I used it on Ubuntu and a Raspberry Pi for IAQ measurement. As a NOT CO2 measurement professional, I found it really amazing how sensitive it is to having a person near it (shouldn't be a surprise, I suppose). Also, I struggle a bit with calibration. Kudos to Co2meter.com for actually covering calibration in the manual, but I still struggle with outdoor calibration. Is my local area really 410 PPM? It reads more towards 500 with no cal. But I digress, because the sensor is very sensitive, pretty low noise, and the manual does discuss different cases of calibration, which to be honest, is more than I expected.

I took the Python sample code in AN127 and tweaked it a bit to make it easier to use as a library, including a bit of port discovery. https://gist.github.com/ErikBrewster/01b1e4669b7c9d2989f84f5a8419d904

Used it to calibrate cheaper sensors for a home air quality hobby project. Very useful.

Very satisfied with the purchase. The sensor came in a couple of days, and it was easy to write a little code on a raspberry pi to read and save the data. The device seems to be very accurate and responsive. I also really appreciate the extensive hardware documentation. It also feels good to support an American hardware company, since the market seems to be dominated by Chinese or Indian sellers.

Great but thought it read temp/rh as well, could make that a little more clear by offering the version that does as well