9-in-1 Indoor Air Quality Monitor Indoor Portable CO2 Monitor | VOC Sensor | Formaldehyde Detector AQI PM2.5 + 4 More Home Monitoring | Air Quality Tester - Air Monitor

I couldn’t operate the first unit, so I worked with AirKnight customer service to get a replacement, and they provided a solution promptly with a detailed explanation on how to operate the unit.

Seems to be monitoring as advertised. Have moved it a couple rooms with different levels.

The first unit I received was defective. The CO2 readings were unreasonably high in every location tested. Shane answered my emails immediately, sent me another unit (which works) along with a postage paid return label for the defective unit. I'm very happy with the product!

Comparing it against all my other meters the values are pretty close within the expected +/- 5% consumer grade accuracy I've come to expect for these grade of monitoring devices. There is one major catch that will have me never buy one of these again. The device ZEROS it's sensors against ambient conditions every time you turn it on. What this means is if your VOC and formaldehyde levels are already high indoors and you turn this on while inside.....it will display everything as being ok when it is FAR from it. To use the device to accurately access an area it must be placed in a known good environment free of any VOC or formaldehydes and allowed to go through it's self zero cycle BEFORE you bring it into the area of measurement. I'm a calibration tech by trade so I've already got the mentality around instrumentation to do this every time. But for most folks, they aren't going to be aware of this and will go about their merry way oblivious to elevated levels in need of proper ventilation.You should have incorporated a calibration mode where you place it in that known good environment and allow it to calibrate the gas sensors and RETAIN that baseline data to compare to every time you turn it on and NOT have it WIPE itself out every time you use it. Then just indicate a calibration schedule once a month or once every three months.That was an utterly moronic design choice. Nobody in the measurement industry does that!

Added this señor for all my 3D printers to make sure the air quality is good

It was easy to set up and use. I’m glad for the CO2 alarm option

Bought 2 of these set them side by side got wildly different readings . Perfume, hand lotion and hand sanitizer all make this read all over the charts even if you you used any of them 15 mins ago

Just barely used it but it’s been working well so far

Great product thanks