AirGradient Forum

AirGradient monitors don't connect to strongest Wi-Fi signal across multiple access points

Support
#1

I have multiple access points in my house. They all have the same ESSID name. Their channel allocation is automatic and changes dynamically based on interference from neighbours.

It looks like my AirGradient indoor and outdoor monitors (I-9PSL and O-1PST) don’t connect to the access point with the strongest signal. It looks like the monitors connect to the access point with the lowest channel number.

It still works if my monitors connect to a far away access point, since the monitors:

  1. work on 2.4GHz which has better range than 5GHz
  2. still work with a weak connection with a very low data rate since they only send a low amount of data

But it’s not ideal, last night one of my monitors lost connection. It was connected to a far away access point. While there is a nearby access point only 2 meters away. This monitor didn’t try to connect to this nearby access point. I had to unplug and plug in the power to restart the monitor so it would connect again.

Can you please update the firmware so the monitors connect to the access point which has the strongest signal?

2 Likes
Help Us with the Wi-Fi Issue of Firmware 3.6.0
#2

Hi @Bart_Netherlands - has this behaviour started recently after the new firmware update (3.6.0)?

#3

Hi @Altair_AirGradient - this behaviour has always been like this since I started using AirGradient monitors April 2025. I forgot about posting about it since it was still working. I recently got a third monitor which lost connection so I thought about it again.

#4

In the past few weeks I’ve noticed my 2 AirGradient monitors dropping off the wifi. One has only had it happen once. The other which has 2 WiFi access points nearby has it happen repeatedly and I’m not seeing it try to reconnect in the router logs. I can’t see why it’s dropping, though failing to try to connection to the strongest signal could be an explanation.

Is there a way to see when the firmware updated to see if that was a linked factor?

#5

Hi @smsm1,

This sounds like an issue with the recent firmware (3.6.0). We are currently investigating the issue at the moment (please see here: Help Us with the Wi-Fi Issue of Firmware 3.6.0 - #7 by tadawson).

In the meantime, if you rollback to firmware 3.4.1, the issue shouldn’t occur.

#6

Not ever having found any release notes to know what 3.6.0 changed/added, that’s a tough call, considering that this happens here once a week, and I know exactly when . . .

Hopefully a fix is forthcoming soon, and I’ll just need to power cycle my outdoor every Sunday morning for a week or two.

#7

Hi @tadawson , there were a few new features added in the firmware V3.6.0. The most significant one is adding support for onboarding the air monitor via BLE, which we prepared to use with our mobile app in a future update. That will help users connect their AirGradient monitors to a Wi-Fi network a little bit more conveniently using our app. Otherwise, it’s quite the same as 3.4.1.

If you find the Wi-Fi issue occurs frequently on 3.6.0, I’d suggest reverting to 3.4.1 in the meantime. You can follow the guides below:

If you use AirGradient Dashboard, please see my reply in: Indoor monitor disconnect and does not reconnect - #17 by Tai_AirGradient

If you don’t use AirGradient Dashboard or prefer flashing an older firmware via PC, please see: Indoor monitor disconnect and does not reconnect - #19 by Tai_AirGradient

Please feel free to let me know if you need any help.

Thank you!

#8

As noted, on 3.6.0, the issue ONLY happens on an AP restart and signal loss . . . rock solid otherwise (I have provided more detail in the other thread), so were I not to have scheduled restarts on my AP’s, I probably would not have seen it at all.

RE: FW notes, any idea why the only firmware page that comes up from AG AirGradient ONE (I-9PSL), Open Air (O-1PST) and Open Air Max (O-M-1PPST...) Firmware Versions that the Firmware page in the dashboard takes you to still thinks that 3.3.8 is the most current? Since this is linked from the live dashboard, I would think that someone would take the modest about of time needed to maintain it, and it would also be a great place formthe change log and release notes . . .

1 Like
#9

@tadawson Thank you for your advice. I heard that the up-to-date firmware web flashing tool will arrive soon. We are working to improve the entire website!

#10

The tool is one thing . . . Actual information regarding changes and releases are another.

There is no reason that I can imagine why they should be related.