NEST Thermostat 3rd Gen will NOT reconnect to home Wi-Fi

[Sunchaser]

I’m looking for some assistance and/or warranty replacement of my NEST Thermostat T3030EX learning thermostat 3rd generation – white.

BASE model backplate-6.5 s/n ################, software version 2.3.23 / 3.1

THERMOSTAT model display-3.7 s/n #################, software version 5.9.5-2

I notice yesterday that it was acting erratic and upon closer inspection had lost wi-fi connection, as well as randomly turning on the heat (which was set to off).  I checked my app, and it lost connection about 3-4 days ago.  I believe we had a power cut at that time.  The NEST thermostat unit had drained its battery trying to reconnect to the wi-fi (which is working normally throughout the house).  I took it off the base plate, and manually charged the unit to +3.86 – 3.92v per some of the troubleshooting steps online.  I reset the boiler, and the unit retains charge when connected to the wall plate powered by the boiler, above 3.8v

No matter what I try, I can NOT get it to reconnect to my wi-fi… which it has been connected to with no problems since purchasing/installing it in late July 2023 – so it is only 1 yr 2 months old, and should still be in full warranty.  It is showing a W5 code error.

I have reset the house router (which still is operating normally for all other devices), I have restarted the unit numerous times, I have reset the networking portion of the unit numerous times.  I have tried to get it to join my iPhone 15 pro (on IOS 18.1) personal hotspot, with no success.  The unit never finds any of the house wi-fi network on its own, it just spins until I tell it to not continue.  I have tried numerous times to add either my house wi-fi network or my iPhone personal hotspot network.  I have moved the unit close to my router with no connection, and the iMac right next to it sees/connects correctly.

Please advise my next troubleshooting steps, or please send me a warranty replacement unit. 

[stevelil]

I have the same issue. i normally show multiple SSID's (WIFI networks on both of my thermostats. about 29 days ago it dropped off the network. and can not find any WIFI networks. i swapped  my two identical nest learning thermostat from two different locations in my house. the problem followed the bad unit. 

[AxelD]

Hi Sunchaser,

Thanks for posting in the Community! Sorry to hear that your Nest Learning Thermostat is no longer connecting to the WiFi. I really appreciate your effort and time doing all those troubleshooting steps, you did all the correct ones. No worries, help is here! Please fill out this form and an agent will contact you as soon as possible with further instructions. Remember to add your thread conversation link in your request.

Let me know once you’ve submitted your form.

@stevelil, thanks for reporting your situation as well. Have you tried the steps to Troubleshoot a Nest thermostat W5 code?

Regards,
Axel. 
 

[Sunchaser]

After submission of the form, I've been contacted by one of your colleague's and offered a warranty replacement unit.  I have completed the order, and it is in the mail.  I will update when I receive and swap the units.

[Sunchaser]

I've received the replacement Thermostat, and it joined my WIFI immediately.  BUT - I dont know how to sync the remaining (original) HEATLINK - I go to equipment and choose heatlink and test, but even after it fails, does not give me an error or offer to enter the HEATLINK code.  Additionally, the new thermostat no longer shows my Hot Water connection.. Any tips please?

[aperezdeleon]

Hi Sunchaser,

Thanks for your reply.

Now that you have a new Nest Learning Thermostat display, I suggest you follow this article on how to reset your Heat Link to factory defaults. This will allow you to pair your thermostat again, as it will indicate a disconnected Heat Link and prompt you to enter the pairing code.

If you're still unable to enter the pairing code, you can also perform a factory reset on the thermostat itself. During setup, it will ask you to enter the pairing code on the display.

Once you've successfully connected your thermostat to the Heat Link, you'll need to set up hot water. You can do this on the thermostat display by going to Settings > Equipment > Pro Setup > System Boiler > (Configure Heating) and then enable hot water.

Please let me know how it goes.

Regards,
Angel.