Co2 level drops after calibration

So I calibrated my pulse pro to outdoor air . Right out of the box outdoor air was coming in at right around 415 ppm. So I calibrated it to 400 and brought it back inside. Now I’m noticing that the co2 levels are down in the high 300s where as before it was in the high 500s . The difference was only 15 ppm in calibration so I’m wondering if this is normal after calibration. The main thing is the huge drop. Almost 200 ppm lower after calibrating . FYI I did not calibrate until about a week after starting it up . Not sure if that would effect anything . Thank you

Hi, perhaps you didn’t leave it outside long enough for the calibration - was the CO2 reading steady before you calibrated?

It was outside for over an hour. It was a completely diff environment from the tent and took a good 45 mins to get stable temps and rh to match outside temps but co2 never stabilized to a point of no change . Would the constant ocean breeze cause the co2 fluctuations? When I calibrated it was at 415 and I went to 400 . I’ll try it again I guess.

From what I’ve noticed and understand the co2 levels go down quite a bit during a lights on cycle from me. It fluctuates from the plants using it I suspect and when my air intake kicks on sucking fresh air in. This could be what your seeing or is the difference really drastic?

Hey buddy,
It could be but the change was so apparent after the calibration. No biggie I’m sure it’s fine. Do you know if that little plug on the side should be opened or closed in normal operation ? Or I was thinking Maybe it’s a com cable for the pulse guys or something.

The plug on the side is a port for additional devices to extend the Pulse Pro’s functionality that we’re planning on developing, it should be closed during operation.

I would try & re-calibrate. You shouldn’t have to calibrate the CO2 sensor upon receiving it.

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