CO2390 CO2 Home Use Meter

They are very efficient and deliver fast

The weather station has a big, bright display and is easy to use. We have it connected to two remote sensors that it switches between with one touch. We can see the temperatures inside, outside, and in our well house so we can be certain it won’t freeze!

This works fantastic, I'm extremely pleased. First, it seems fairly accurate. I put it outside for 10 minutes and it stabilized at 408ppm, which is within 10ppm of what the true outdoor measure should be. I'm mostly impressed that it is sensitive enough to measure the presence (or lack of) people in a room. With 2-4 people the room CO2 can rise 100-200 ppm, while at night with no-one in a room it settles in at a much lower level. Just standing next to the sensor for a few minutes can change the eventual value quite a bit. So really great to know how much air is being exchanged in your house and how fresh the air is. Because it's also battery powered, I'll probably take it to other places I frequent just out of curiosity. One thing you should be aware of (and I expected) is that it doesn't react instantly to new readings (like if you breath on it). Instead it's a running average of measurement, so a breath on it might take a minute or so to spike, or a few minutes to adapt to a new room. I'd let is sit for a long and let it stabilize for more accurate readings. Overall, great purchase, very pleased, and can't wait to try recording data!

I am very happy with this unit. I find that it is fairly accurate as outside I get almost exactly the readings NOAA provides. It says it has an error rate of 50ppm (which is nothing) but at least mine seems to be pretty spot on. I am going to use this meter to test sources of co2 in my greenhouse. One thing I really found facinating was the high concentration of co2 in my house during the winter. It climbs up to almost 1500ppm. I live in an old building. It was built when ventilation was not a priority in the building code. Anything over a 1000 ppm could cause headaches sleepiness and even a 20% loss in cognitive ability. This meter is turning out to be more useful than I could have imagined.

I've tried quite a few CO2 detectors and this is by far the most accurate and STABLE device I found. As soon as I plugged it in when I received it, it showed an accurate value when I placed it outside with differential of about 5%, which is great. Since about a month, it's been working stable without a hitch. The only thing I wish it had is an option to calibrate, in case if the sensor gets less sensitive with time. Other than that, the price could also be in the range of $120 to compete with other products.