Nest temp sensor not working or connecting

[cook129]

I had a working sensor in my house until about 8 months ago.  I have tried to replace the battery a few times, but he sensor still said it would not connect. The sensor was removed from the account and I am trying to reconnect it.  I have yet to get a successful try after using the troubleshooting recommendations.  Is my sensor bad or is there something else to try?

[dansviol]

Also having this issue

[Markjosephp]

Hello folks,

Thank you for taking the time to let us know about your inquiries. I'd be happy to take a look at this.

Going over these steps might help:

1. Move all the Nest Temperature Sensors close to the Nest Thermostat.
2. Restart all devices, including the router, by unplugging and replugging it for at least 3 minutes to refresh the connection.
3. On the Nest Thermostat. Go to Settings > Reset > Restart to refresh.
4. Ensure that the thermostat is still connected to the Wi-Fi network.
5. Proceed by adding the sensors back to the Nest app.

Let me know how it goes.

Regards,
Mark

[Bramasole-1]

Hello,

I am having the same issue. The sensor worked fine for months, then 2 weeks ago unpaired itself from its thermostat and I cannot get it to re-pair. I have already removed and reinstalled the sensor and reset the thermostat to no avail.  Next steps would be appreciated. 

thanks

[Molinab]

I’ve tried the steps above and sensor still not working, I replaced the batteries in all three. I removed the sensors from the account and added them again . 

[Addax]

Having a similar problem. The sensor worked perfectly for about a year. Then I suddenly found it offline. Measured - the voltage of the battery is normal. All attempts to remove it and add it back in the application have failed. The sensor is added, but communication with it is not established. Replacing the battery with a new one did not help. The same problems. Bought a new sensor. Same problem with new sensor. The thermostat has been factory reset. Both sensors are connected to the thermostat without problems. The new sensor has been returned to the store. A week later, the sensor was offline again. Another factor reset of the thermostat. Everything works again. 5 days have passed the sensor is not online. Writing this message.

[zoeuvre]

Hi everyone, 

@cook129 and @dansviol, how's it going with your Nest Temperature Sensor? Were you able to read the steps that that Mark shared? In case you have an update, let us know and we'll be happy to help.

@Addax, thanks also for reaching out to us, and I appreciate the steps you took in solving the situation. Please let us know if you still have questions or concerns, as we'll be willing to assist you more.

I appreciate your help, Mark. 

Best,

Zoe

[Addax]

Yes, the steps work perfectly. But somehow I still have a question. Is Google's thermostat software meant to factory reset every few days to keep in touch with Google's temperature sensor? Why wasn't this a requirement last year?

[cook129]

I have tried repeatedly all the steps and my sensor only purchased 2 years does not work..

[Markjosephp]

Hello there,

Thanks for your assistance here, Zoe.

@Addax, there's only one situation where we require it: to make sure they communicate with each other. In some instances where a restart did not help, resetting is the best option to reconnect to your Wi-Fi network, as this issue happens when they can't see each other because of the internet connection.

@cook129, I appreciate the steps you've taken. Can you help me gather your thermostat's power readings from the Technical Info settings? I'll look forward to your response.

Regards,

Mark

[Markjosephp]

Hi there,

I wanted to follow up and see if you are still in need of any help. Please let me know if you are still having any trouble from here, as I would be happy to take a closer look and assist you further.

Regards,

Mark

[Addax]

For the last 2 months I was doing a hard reset once or twice a week to re-establish communication with the sensor.
If I just remove the sensor from the app and add it again, the thermostat won't be able to connect to sensor. If I reset the therostat to factory settings, add it back to the app, and then add the sensor (I literally don't touch the sensor during the whole process, it's in one place, I just scan the barcode I pasted on the front of the sensor) then everything starts working immediately. For a few days.
The application shows that the battery level is normal.
If it is somehow important I have tried both 2.4GHz and 5GHz WiFi, no difference.

[Molinab]

I need some help, given that others are all having the same issue- is this a system wide problem due to a software upgrade?

[Markjosephp]

Hello Molinab,

I appreciate you for chiming in about your issues in reconnecting your sensors. In addition to the steps above, please perform an Account Connection reset on your Nest Thermostat in the Reset settings. This will disconnect your thermostat from the network and unlink it to an account. Once done, reconnect it to the Wi-Fi network and add it to the Nest app. 

As soon as the thermostat is completely added, attempt to add the Nest Temperature Sensors to the app by having them near the assisting device. Let me know if it works for you.

Regards,
Mark

[toymanaf]

Same issue here and read and tried everything in this thread.  The “fix”worked for a few days and just lost connection for no reason.  This is extremely disappointing…. The fix offered by the experts can’t be to continually reset everything!! This wasn’t an issue for a year or two, then this issue started so obviously something happen with the software that is now creating this issue. Please find a real solution…. Completely unacceptable.

[Markjosephp]

Hi toymanaf,

I'm sorry for the inconvenience it caused you. Please make sure it's within a maximum of 50 feet (15 m) of your thermostat, so the sensor and thermostat can communicate wirelessly. You may need to place them closer together because the wireless range can be reduced by walls, floors, appliances, furniture, and other electronics. Also, check that the Nest Thermostat's battery level status is in good condition with 3.8 volts.

Best,
Mark

[toymanaf]

Thanks for the reply…however, I’ve gone through all of these easy steps to correct. My sensor has need in the same location for over a 15 months.. Battery has been replaced. I’ve removed the sensor, reset the thermostat, logged out of the WiFi, removed everything from the app, rebooted, reset, etc. After all this the sensor worked for two days and lost connection again. I actually left the sensor in the same room as the thermostat and router to ensure nothing was interfering with the signal.  Again, my setup worked for 10 or 11  month. It’s obvious that there is glitch in the software based on similarities on how many people are having similar issues.  Us there anything new that can be offered up as a fix….. not I’ve read all of the posting.

[Markjosephp]

Hey toymanaf,

Got it! I applaud your effort looking for answers in the forum. We'd like to jump through hoops for you.

Could you please fill out this form with the needed information? A member of our senior support team will be in touch via email to help. Let me know once you're done.

Regards,
Mark

[Markjosephp]

Hi there toymanaf,

We haven’t seen your form submission come through - were you able to access it alright? Let us know if you’re running into trouble or still need our help!

Regards,

Mark

[HalKunnen]

I just had this problem of a remote temperature sensor stop working after losing power to the main thermostat due to work on the air hanger breaking the pier for a long time. This drained the battery on the NEST thermostat such that it had to recharge before the WIFI app on my phone would connect. It took a couple of days to read your troubleshooting tips to realize that Google software on the BEST thermostat needed a total reboot to connect to its remote sensor again. I think this is a bug in the software where power is out and the battery drain interrupts sensor configuration data. Others are having the same problem so it should be an easy software fix for the next update. Hint hint

[HalKunnen]

First post. Sorry for the typos. Pier should be power; BEST should be NEST. 

[Egriff88]

I’m having similar issues, like everyone on this thread. My sensor has been offline for about a month now, and I finally changed the battery out. That has been a mistake so far. I’ve tried 6 different batteries, removed the sensor/added it back, factory reset the the thermostat multiple times, also reset my router/modem, yet it’s still not able to connect to the sensor. PLEASE HELP. 

[HalKunnen]

Check the reply by me. I figured it out but forgot already. Your master NEST thermostat battery probably ran out of power when the air handler power turned off too long. The battery loses charge in the master thermostat and reset its program to forget any remote sensors. 

Reset your thermostat software. It is a big in the NEST thermostat program. 

[HalKunnen]

Big should be bug. Someone needs to type more better. 

[Egriff88]

Just did everything that I was instructed to do, and it still isn’t connecting to the sensor. Connected to the one in the main room, but not to the bedroom sensor. 

[Markjosephp]

Hello there,

I know it has been a while, but I wanted to ensure that everything was covered here.

To ensure that the Nest Temperature Sensor communicates with the Nest Thermostat. Check the thermostat's battery level if it drops to 3.7 volts. If it does, pull the display from its base and charge it for an hour before plugging it back in. Once the thermostat is ready, check the battery level to ensure it's good to go, and make sure that it's still connected to the Wi-Fi network. If so, restart the sensor to refresh.

Let me know if that helps.

Regards,
Mark

[Markjosephp]

Hi folks,

I'm checking back in. Were you able to do the steps above? I'd be glad to hear from you — I'd like to make sure everything is working.

Thanks,

Mark

[HalKunnen]

Yes. It is working fine now. When the power goes off though, the WiFi network credentials and the remote temp sensors credentials need to be restored to memory in the thermostat. Hopefully power never goes out again?!!  Keep the steps to recover published or get a firmware fix that prioritizes long term memory for WiFi and sensor credentials. 

[Markjosephp]

Hello HalKunnen,

Thanks for the update; we'll take it as feedback. I'm glad to hear that your temperature sensor reconnects back to the network. In case you need more information about this, please check out the Troubleshoot Issues with the Nest Temperature Sensor article for some steps that would help. Also, if you have any other concerns or questions, please feel free to create a new thread.

Thanks,
Mark