Temtop LKC-1000S+ Air Quality Monitor Formaldehyde Detector, Air Pollution Sensor, Humidity and Temperature Meter Tester with PM2.5/PM10/HCHO/AQI/Particles/TVOC VOC/Histogram

I already have a Temtop LKC-1000S+ handheld air quality monitor(measuring device), bought from Amazon 3 years ago. I am not technical so I cannot say if it is 100% accurate, but its measurement results are definitely CONSISTENT with what I have learned to I expect. I use it to identify as early as possible, when I should start taking extra precautions and extra medicines before my chronic asthma flares up again due to environmental conditions. I have been and still am delighted with this great device. I have ordered a 2nd one now (March 2021), as a backup in case my current one conks out (currently there are no signs of trouble), in case I cannot get another (same) Temtop device via international courier from Amazon, due to ongoing Covid lockdowns. . I highly recommend this product. (I removed the Warning: it was not applicable to this Temtop).

This air quality monitor is great. It's easy to use and very accurate. It helped me see how much dust I was kicking up when I swept as opposed to using my HEPA vacuum (on a hard floor). Certainly has helped me keep my house a LOT CLEANER.

This monitor measures PM 2.5, PM 10, VOC, and Formaldehyde. The particle sensor seems very accurate. I tested it outside several times and it was very close to one of the purple air monitors not too far away. It seems accurate for both bad and good air quality. It also seems very sensitive to VOC. It usually measures the VOC inside my house between 0.14 and 0.19. My wife uses these Noxema cleansing pads on her face before bed and one of the main ingredients is isopropyl alcohol. I had the monitor running and it was showing 0.18 for VOC. My wife took out one of the Noxema pads and within 10 seconds, VOC started climbing. The monitor was all the way across the room, but it picked up the VOCs (probably the alcohol) from the pad. Within 5 minutes, the VOC was at 5.00 and then it started going back down. I repeated this the next night and it behaved the same way.I do not trust the Formaldehyde reading at all. It reads 0.04 inside my house and 0.02 outside in fresh air. I've noticed that it is impacted by the VOC readings. If the VOC is 0.15 to 0.18, Formaldehyde always reads 0.03. If VOC goes above 0.20, Formaldehyde jumps to 0.05. When I was testing the monitor with the Noxema pad and getting a VOC reading of 5.0, the Formaldehyde reading was 2.34. I do not think that there is any Formaldehyde in the Noxema pads. I am not sure if the device is calculating a certain amount of Formaldehyde based on the VOC, or if there's something else going on. All I know is that this is the second of these devices that I've had (first one was returned because it always read AQI of 0 and virtually no particulates) and they have both acted exactly the same way.Another plus is the Elitech support. They worked with me during the time that I had the original defective device, and they sent me a new one. They have checked in periodically to make sure that everything is working out ok. They seem to care about their customers.I'm not really sure if there is a good consumer device to measure Formaldehyde. I don't think this one really measures it. But this device does a good job at detecting other air quality issues.

I dont know if the device was refurbished, used, or just poor quality control but the screen has a scratch upon removing the protective film. The film was bubbly as if it has been removed already. Ordered a replacement and will wait to see if the next one is in new condition.

We are using this device to monitor indoor particulate levels during California's extended fire season. It has been enormously helpful. I have taken outdoor readings and compared with other measures such as Purple Air, and it seems to be accurate enough. It helps us decide when to crank up the air filters and when we can afford to open windows.

The package arrived safely. The packaging was well done - gave me a high expectation of the product quality. The build and display also was well done.The accuracy was highly questionable, though. I wave it above an open bottle of bleach. No change in TVOC reading; I wave it between two OSB that I am 80% sure have high formaldehyde emission, no change in HCHO reading; both while other handheld air quality monitors I tested shows significant increase in TVOC / HCHO reading.I understand that this is a low cost AQ monitor and we shouldn't expect professional results. But the way it is useless to me. I did not spend time verifying its PM2.5 / PM10 accuracy.The word histogram was used in the product description. Whoever wrote the description clearly did not understand the term. What this product has is not histogram, but a display of result history.By the way, "histogram is only available for PM2.5 and HCHO, not TVOC or PM10. For TVOC or PM10, all you can see is the current reading. Not a useful instrument even if the readings were accurate.