Need help diagnosing sporadic reporting

I’ve had my PurpleAir sensor set up under my front eaves for the past year. I live about 40 miles from Mariposa, and while checking for smoke impacts I noticed that my sensor is only reporting sporadically. For example, yesterday it didn’t report any PM 2.5 data between 2pm and 6:50pm. It does seem to be reporting PM 0.3 data more regularly, though there are still some gaps, and compared to other sensors nearby it’s reporting about an order of magnitude lower levels of PM 0.3.

Around 11am yesterday I cycled the sensor (disconnected it from the power supply) for a minute, and also cycled my router. The sensor reported values more regularly for about 3 hours, and then the 2-6:50 gap.

I’m not sure what to do next. Take it down and vacuum it out?

Is your graph loading slowly? Recently I have also had problems.

Graph loads very slowly - more than 30 seconds …desktop & tablet - tried Firefox & Brave - same
issue. Its like this for long time. The small sensor info box comes up quick as usual.


This morning I also noted fallout in reporting - and it did not report neighbors wood burning - tho I could see that on the sensor pop-up info.

Follow up - graph now caught up with map. So now graph looks right.

Seems to be a significant delay in graph showing sensor data?

Hi @danhicks, if the time that the sensor disconnects is consistent, I believe the issue may be with your router or internet settings. Does your internet go down at specific times, or do you turn off the router?

We can also check if the sensor is receiving power. Do you see any lights on inside your sensor during the outage time?

We only recommend cleaning out the laser counters when one of them is reading inaccurately. In this case, it most likely would not make a difference.

No, it doesn’t appear to be a problem with the website, but with the sensor itself

It doesn’t appear to be consistent. Here’s the raw, un-smoothed PM2.5 since about 6am yesterday morning. (There was a spike around 4am that shows up on other sensors nearby and throws the scale off.)

The data for today looks a bit noisy, as you’d expected from un-smoothed data. But yesterday’s data looks very un-noisy. This is because there’s no data for large, irregular periods of time. Between 12:48pm and 2:20pm there are only 4 reported values (at 1:04, 1:08, 1:34, and 1:40). I don’t remember exactly what I was doing during this time — I was at home, having lunch and then working, but I might have been reading and wouldn’t have noticed connection issues. There’s nothing between 3:02pm and 5:26pm. I left the house at 3:30 and didn’t notice any connection issues during the half hour prior to leaving. Around 9:48pm the sensor starts reporting every 2 minutes. Between about 7-10:15 I was watching videos on YouTube and wasting time on Twitter and Reddit. I never noticed any connection problems.

When I wrote the original post, I was able to connect to the sensor’s local IP successfully. All 6 PM µg/m3 values were reading 0. I’ll try to check this again if I notice a gap in the data when it’s happening. The downloaded logs for yesterday have 719 entries. My sensor doesn’t have a SIM card, so I assume it doesn’t have a way to store the data locally and upload it when the connection’s restored?

After several days where the sensor was working as expected, I caught it just now in a sporadic reporting event. I was able to connect to the sensor over the local network and it’s reading 0 for everything except the smallest particles. The most recent real-time PM2.5 value on the map is 5, and nearby sensors (within maybe 3 miles) are reading 5-7 on the map.