DIY Pro Kit PM Concentration Missing

Components
#1

Hello, I bought the DIY Pro Kit as my first electronics project. I assembled it and got it running with this github repo GitHub - ajfriesen/ESPHome-AirGradient: ESPHome config for AirGradient Air Quality Sensor for home assistant integration (I had to install the PR to get the temp/humidity working). It is using the defaults for air-gradient-pro-diy.yaml.

Upon monitoring the results I get 0s for Concentrations. I’ve had it running for several hours a couple of different times. The logs are also filled with the info below every second. I don’t see any log for sensor output on PM.

Name State
AirGradient Pro Particulate Matter <1.0µm Concentration 0 µg/m³
AirGradient Pro Particulate Matter <10.0µm Concentration 0 µg/m³
AirGradient Pro Particulate Matter <2.5µm Concentration 0 µg/m³
AirGradient Pro Particulate Matter >0.3µm Count 168 /dL
AirGradient Pro Particulate Matter >0.5µm Count 46 /dL
AirGradient Pro Particulate Matter >1.0µm Count 4 /dL
AirGradient Pro Particulate Matter >2.5µm Count 0 /dL
AirGradient Pro Relative Humidity 28.37 %
AirGradient Pro SenseAir CO2 Value 1171 ppm
AirGradient Pro Temperature 24.97 °C
Flash Mode (Safe Mode) OFF
NOx Index 1
Uptime Sensor 783 s
VOC Index 99
WiFi Signal Sensor -65 dBm 
12:26:35	[W]	[component:214]	Component sgp4x.sensor took a long time for an operation (0.06 s).
12:26:35	[W]	[component:215]	Components should block for at most 20-30ms.
12:26:35	[W]	[component:214]	Component ssd1306_base took a long time for an operation (0.32 s).
12:26:35	[W]	[component:215]	Components should block for at most 20-30ms.
12:26:36	[W]	[component:214]	Component sgp4x.sensor took a long time for an operation (0.06 s).
#2

Since you do see values for the Count, but not for Concentration, I suspect you just don’t have high enough concentration to register above 0. I often see this when I have my AC or furnace running and air get filtered regularly. In those few weeks where the temps don’t require either, I see an increase.

You could try bringing your sensor outside to see if you start seeing above 0 as I almost always have something while outside.

If you think the code may be responsible (and I don’t think it is) you could also try one of my configs that is very similar:
GitHub - MallocArray/airgradient_esphome: ESPHome definition for an AirGradient DIY device to send data to HomeAssistant and AirGradient servers

Also, don’t worry about those warnings about things taking a long time. It is a known issue with ESPHome right now. My configs have an increased I2C speed to try to address it, but the SGP40 sensor still reports it, so I hid the warnings.

#3

I agree with @MallocArray. You might just have very good air quality. You could also just create some smoke near the sensor module eg with a candle or a soldering iron.

#4

@MallocArray @Achim_AirGradient Thank you. After further testing I was able to see it jump between 0-1 throughout the day, but now I have the opposite problem. Does it take awhile to acclimate for the data to calibrate? In this case I’ve seen a spike at 5PM to 350 µg/m³. The AC was not running at the time. I am at least getting data now, but this seems quite drastic sudden increase but maybe it is good sign that air gradient is at work and the troubleshooting the air quality can begin.

Screenshot 2023-11-01 at 8.04.20 PM

#5

Did you do anything to create that spike to 350 or did it just happen?

#6

Not to my knowledge. Still trying to figure out and replicate it. A few smaller spikes happened since then but nothing obvious or that large. AC didn’t kick on, no sudden environmental changes. Was zero all day and check the charts and there it was.