Reassigning your Sensor's Current WiFi Network

Sensors
1

This is a technical guide that lists a couple of options to help you connect your sensor to another WiFi network other than its currently connected network, or to connect it to a network when your sensor is not broadcasting its PurpleAir-**** WiFi network.

Note that if your sensor is not broadcasting that network, you should first follow the steps we list in this section of our WiFi Troubleshooting guide. While we don’t normally recommend these options when your sensor’s WiFi network isn’t broadcasting, you can try them if all else fails.

The options below may not be replicable for all devices. You can try either option listed, as one may be more viable than the other for your situation.

For both of these steps, you’ll need to find the IP address assigned to your sensor by the network it is currently connected to, or by the network that you connect it to in this guide. If you have access to the WiFi network that the sensor is currently connected to, you may be able to look up the IP Address assigned to the sensor by your router. You may also be able to look it up by the sensor’s hostname, http://purleair-****, where the asterisks are replaced with the last 2-4 characters of your sensor’s MAC address (the last two octets).

Option One: Connecting to Your Sensor’s Current WiFi Network

When using another device that is connected to the same WiFi network that your sensor is currently connected to, you can enter the IP Address assigned to your sensor in the address bar of any web browser to navigate to the sensor’s interface. A configuration page should appear, at which point you can follow this section of our Sensor WiFi and Registration guide to connect your sensor to an accessible network on the configuration page.

Option Two: Using a Mobile Hotspot

You can create a mobile hotspot on your phone that a PurpleAir sensor will connect to automatically when it is booting up. To do so, create a hotspot named “PurpleAir”. This must have no spaces, and the P and A must be capitalized. The hotspot will need its password set to the device ID, precisely as written on your sensor, except that all characters should be in lowercase. Ensure that all colons are included.

Once the hotspot is broadcasting, restart your sensor. As the sensor turns on, it will connect to your created hotspot. You can then enter the IP Address assigned to your sensor by your hotspot in the address bar of any web browser to navigate to the sensor’s interface. A configuration page should appear, at which point you can follow this section of our Sensor WiFi and Registration guide to connect your sensor to an accessible network on the configuration page.

Learn More

Sensor WiFi and Registration

WiFi Troubleshooting

The PurpleAir Utility

1 Like
Can’t See the Sensor's Network
Wireless Connection Failing
Cellular and WIF signal
Indoor Sensor Live View
Channel B downgraded
How to Obtain Sensor Data
No Pop-up Window after Connecting to WiFi
Sensor will not save WiFi password
Network Checklist
Flex sensor went offline, red power led is on
Map Troubleshooting Guide
8

I recently ran into a situation where I wasn’t allowed to make the configured wifi network unavailable, but I didn’t have access to the router to figure out the ip address. It would be really handy if there was another way to reset the wifi information – perhaps via logging onto my account on the PurpleAir map and then selecting “reset wifi” somehow for that monitor. I should only be able to do that for monitors I installed and have connected to my e-mail address. Maybe this is more of a feature request? Is there a section in this community forum where we can post such feature requests? (And then maybe vote them up or down and debate them?)

Thanks for creating this community forum!

Best,
Mark

9

There is another way.

  • Create a hotspot called “PurpleAir” with the password being the sensorId EXACTLY as printed on the sensor’s label.
  • Restart the sensor.
  • The sensor will connect to that hotspot.

You can then connect to the sensor either from the hotspot device if it is a phone or from another device connected to the hotspot.

The trick is, you need to know what IP address the sensor has on the hotspot. That may not be the easiest thing to do. You could guess based on the IP of another device connected to the hotspot, scan for it or use software or status info on the hotspot to see connected clients and their IP address.

Any way you do it, you will be able to connect to the sensor on it’s IP address at http://IP_OF_SENSOR and configure it as needed.

1 Like
10

Thanks for this! I’ll have to experiment with it. It could prove to be a very helpful way to update my monitors.

11

Hi Mark, we appreciate the idea you have given here and we have gone ahead and created a new category named “User Experience” for this. This category includes subcategories for feedback, bug reports, and feature requests, so feel free to make posts there for future requests!

1 Like
12

Thanks so much! Can’t wait to add ideas to that section. :slight_smile:

13

It would be so simple - just turn on both the wifi server and the wifi client at power up. The server continues to run for several minutes after wifi setup for the client is completed, so I know both can run at the same time.

To reset the connection, one would unplug and then power back up - for serveral minuts the user would have access to the wifi configuration page.

14

I have a PA-II sensor I’ve had for about 5 years. It’s always been connected to the same ASUS wifi router with the same id and pw. The problem is it has stopped uploading data and I’m not seeing it in the connected device list when I go to my router client list.

I did take the sensor to another location, well outside of range of my home router to access the sensor from my phone using the PurpleAir hotspot of the sensor. But it never shows up.

I tried the trick above about creating a hotspot on my router with name PurpleAir and pw of the Device-ID but that also didn’t work. Again, the PA-II sensor never showed up in my list of clients on the router.

I now have the Sensor sitting here outside of the case so I can visually see the red status light. I can also hear a slight hum from the sensors themselves. So the device is powering up.

Anyone have any suggestions on how to proceed? Has anyone had the wifi on a PA-II simple fail?

15

I had the same thing happen. Just dropped off the network. Power light is on and the sensor fans are spinning, but even the hotspot trick doesn’t work. Wish I could buy a new board…

2 Likes
16

I have two of those sensors. Red light on, not connecting to WiFi and not showing a local WiFi to connect to. This is getting pricey if sensors only last a few years.

17

Reloading the firmware fixed this for me.

18

How do I reload the firmware

1 Like
19

I just got a brand new Flex sensor. The hotspot will not show up on my iphone 16pro, after waiting 1 min, 10 min, or 30 min. I rebooted multiple times and no luck. I was going to try this PurpleAir hotspot solution, but the latest iOS does not let me name my broadcasting hotspot SSID.

I have no idea what to do next. It’s a brand new sensor, what is the issue and should i just get a new one?