ECOWITTWH0290 Air Quality Monitor Meter PM2.5 Detector Indoor Outdoor with Temperature and Humidity

This PM 2.5 sensor works well. Outdoor unit charges via included solar panel. Has weathered rain fine so far. Sensor appears to be accurate relative to other sensors I own and use as well as national and regional data sources. Indoor Temperature and humidity readings are also consistent with other gauges I use. Recommend.

As super hot dry summers and smokey air from forest fires becomes a new norm with global warming, I wanted to have an indoor AQI meter to know (not just feel) how to run my air filters. This unit is specified to have accuracy of 15%. I took the sensor outside and compared its reading with values reported on PurpleAir web site; there are 3-4 privately owned sensors within a mile from my home which report into the network's database, so I can interpolate their readings and compare with what ECOWITT shows. In the range between AQI of 7 and 50, the agreement is very good (within the stated error range). I like that the unit shows both density of particles and AQI, as well as temperature and humidity (which also reasonably aligns with other gauges which I have at home). The screen is large and easy to read (although it gets a little too dark when light is poor). I like that it uses a laser particles sensor, which is the same type of metrology which more sophisticated and expensive units use. Rechargeable batteries for the sensor are included (and in bright light it can recharge from sunlight using built-in solar cells, or one can plug it in into any USB charger using included cable). One only needs one alkaline battery for the unit with the screen. Manual is well written by someone who knows English (not very common with goods from China!)

I've had this running for a little over a month now and have been VERY impressed with its accuracy--it corresponds almost perfectly with local official air quality readings. It is also very responsive and quick to show changes in air quality (I was concerned about this before I bought it since it has no fan to aspirate air in like many AQ monitors)The solar panel also works amazingly well and I have never seen the battery indicator show a loss of more than one bar. It has been a very bright and intense summer here, so I'm not sure how it will do when it is overcast. It also receives the signal very strongly through many walls.For the money I wish the sensor also had a thermometer and hygrometer in it like the display does.

This seemed to work great and accurately measure the air quality based on a nearby metrics, but the included display (which sits inside and pulls in air quality data from the monitor outside, along with indoor temp and humidity) requires a single AA battery (not included) to operate and strips the battery so quickly that it only works for an hour at most before the battery is dead and it stops pulling in data. The first time it happened, I thought maybe the included batteries with the aqi monitor were drained, but I charged them and they were completely full still. Replaced the battery, and the same thing happened again. Doesn't matter how accurate the reading is if I can't read it because the display dies immediately! It's too bad, this would have been the perfect solution.

The sensor portion of air quality detector can be outside and still connect to panel wirelessly. It seems to be not quite accurate with the professional air quality monitors in my location. However it still tells me what I need to know. In my house the meter reads about 5 to 6 with a air purifier in the room. When outside it reads anywhere from 10 to 200 depending on how bad the air is. I live where there is always fires, California. So when the pm2.5 is over 40 I know the air is getting bad. I wish this monitor would list AQI. I use a AQI calculator to get those numbers. When the sensor is in the house and my wife sprays hairspray in the bathroom it will detect it in the bedroom. It will go up from 5 to 40. I am glad I got this. I have two air purifiers. With the one air purifier I get a reading of 5 with the other air purifier I get a reading of 8. I think this meter might be good to see if ones air purifier is working properly.

UPDATE 12/3/2023 - After using this for a few months it stopped working yesterday. I tried charging the batteries overnight, but after testing one batter was completely dead and non-rechargeable. After replacing with other batteries, it still doesn't seem very accurate. The morning readings are very high and seems to level off during the day. But still not close to AirNow.gov, IQair or national air quality readings in my area. I really like the meter and price and Ecowitt products but need a more accurate consistent reading.UPDATE 8/5/2023 - After using meter for a couple of weeks I've noticed inconsistencies in the PM2.5 and AQI reading. In the morning it is super high (PM2.5 173, AQI 223) and wonder if I should even go outside. Then after a couple hours after the sun come up a huge difference of PM2.5 2, AQI 8. That can't be correct?? The AirNow and my Davis AirLink readings seems to more consistent with local EPA readings. Debating whether to send it back or not.---------------------------------------------------------------------------------Very nice and reasonably priced AQI/PM2.5 meter. Super easy to setup and my Ecowitt weather station recognized it immediately and display online. I've had it for a week now and have been very impressed with it. It is pretty close to AirNow air quality readings. I have it mounted in the backyard on the same pole as my weather station, so it gets the best air quality readings.The solar panel seems to work ok and displays 100% charged so far. I live in central Florida, so I get pretty good sun during the day.Looks exactly like the Ambient Weather PM25 but cheaper and has display. I would have given it a 5-star, but the only disappointment is it hard to read the display and the website looks like it has a backlit display which it does not. Other than that, not a bad air quality sensor for the price.

Fonctionne très bien, le panneau solaire charge bien les batteries.J'utilise toujours les batteries d'origines depuis 1 an.Et fonctionne aussi, très bien à l'extérieurJe le recommande pour les gens qu'ils veulent savoir la qualité de l'air dans leur cour ou dans la maison.Il s’installe rapidement avec le récepteur GW1000 et fonctionne aussi en même temps sur Moniteur WH0290