Nest 3rd generation thermostat not connecting to network ~ UK

[geechr]

My Nest thermostat has been operating perfectly since April this year including being able to use the app on my iPhone.  However, this week it has stopped being able to connect to the network.  It is working as it should do locally 

The setup is as follows:-

NETWORK 

Virgin router set to modem mode

TP-Link Deco mesh wi-if system.  The master Deco unit plugs into the Virgin router/modem and provides network coverage using three satellite Deco units.  The system is working at both 2.4 and 5 GHz.  

PHYSICAL

The Nest is 3m from the master Deco unit.  My iPhone has a very strong signal when placed 20cm from the Nest
The Heatlink is linked by cable to the Nest

There are no sources of radio interference in the house

ACTIONS TAKEN 

Virgin router rebooted and restarted

TP-Link Deco system rebooted and restarted

Network name and password re-entered on countless occasions 

Nest restarted on countless occasions

Attempted to link the Nest to a wireless hotspot on my iPhone.  The Nest immediately displayed a message stating that it could not join so no search was initiated (I assume)

No NestWeave status shown.  However, it does state that “Last cloud com” was “Never”.  How can this be correct?

One curious thing I have noticed that during a Nest restart sequence I can see on the TP-Link Deco network monitoring app that a new device has connected.  It disappears quickly but I have been able to take a screenshot showing the MAC address.  It’s not the same as the one shown on the Nest technical information display.  Of course, this may be a coincidence…

I’d appreciate some help from more knowledgeable people

Regards Chris G

[TudorL]

Hi there and thanks for reaching our community. I'm sorry you're facing this issue, but I'll do my best to assist you. By any chance, did you notice any error codes on the thermostat display? 

[geechr]

Hi, no error codes are shown 

[AlexD]

Thank you for the information. Go to Settings> Network and let me know if you see any message there about it not being able to connect or it tries to look for networks and eventually states they may be hidden or too far away. 

[geechr]

The message is shown on the photo.  See also in the shot my iPad with the network strength shown

[UanaC]

Gotcha. Let's try to perform some restarts on the thermostat. Please grab the thermostat and pull it gently off the base. Hold the thermostat with both hands, let's say like a hamburger. Press the thermostat and keep it pressed until it reboots. Do this three times, one right after another. Let me know how it goes.

Many thanks, Oana.

[geechr]

I have rebooted as follows -

• Taken the thermostat off the wall
• Held it like a hamburger and pressed until I heard a click
• I noticed a flashing green light turn on, go red momentarily and then back to green
• After a while the Nest house appears, then it disappears for a while and then returns
• Eventually the words “Please attach the display to the base”
• This was repeated 3 times
• The thermostat was reattached
• The thermostat does not reconnect so I went to network settings and input the network name and password (WPA2 security)
• Immediately after the password is entered and confirmed a message stating “Failed to connect “ appears.  So no network search??

Any suggestions?  Am I holding down the dial for too long?

Chris

[UanaC]

Thank you so much for doing this. You did the restarts correctly. Can you please let me know if you see any error messages if you go again to Settings-> Network again?  

[geechr]

Please see photo. 

[geechr]

This message also appears

[AlexD]

Thank you for the pictures and trying the steps. I would like to create a case so we can look further into this. Would it be ok if I sent an email to the one associated with your account here? 

[geechr]

Yes, that’s fine.  The email is mine.

[AlexD]

I sent the email out. Once you go through it and reply to the form, make sure to let me know here so I, or one of my colleagues, can check. 

[geechr]

This may not help but I have another Nest thermostat ( I don’t know which generation) in another house. Could I push it it onto the base and see if that one worked?

[AlexD]

You can certainly try, though generally the Wi-Fi connection should not be affected by the base. The Wi-Fi chip is located inside the display part. 

[geechr]

AlexD

I did not make myself clear, I was proposing to change the display part

geechr 

[AlexD]

You can certainly swap the display with another, if you have one on hand, and that one will most likely work but there are complications such as if it's connected to another Heat Link wirelessly. Let me know if you received my email. 

[geechr]

I have completed the form you sent me.  

[LarisaL]

Hi there! Can you please answer a few questions just to document the case properly?

1. You mentioned you have more than 1 router, do any of them end in _ext?

2. When was your thermostat installed?

3. How far away is the thermostat from the router?
4. Are there devices or appliances (such as baby monitors, microwaves, cordless phones, etc.) near the thermostat?
5. What’s the make and model of your router?

Also please try these steps as well:

1. Reset the thermostat's network - Settings and then Reset and then Network
2. Reset the thermostat to default settings - Settings and then Reset and then Reset All Settings

Many thanks, Larisa. 

[geechr]

Larisa
Please find the answers to your questions in bold below
1. You mentioned you have more than 1 router, do any of them end in _ext?
No
2. When was your thermostat installed? 
April 2023.  It worked perfectly until two weeks ago
3. How far away is the thermostat from the router? 
The Nest is 3m from the master TP-Link Deco unit.  My iPhone has a very strong signal when placed 20cm from the Nest
To help I have copied more information from my first post:-

NETWORK 
Virgin router set to modem mode
TP-Link Deco mesh wi-if system.  (Information here https://www.tp-link.com/uk/home-networking/deco/deco-m9-plus/ ). The master Deco unit plugs into the Virgin router/modem and provides network coverage using three satellite Deco units, which are located around the house. The master Deco is the closest to the thermostat by far. 
The system is working at both 2.4 and 5 GHz.  

4. Are there devices or appliances (such as baby monitors, microwaves, cordless phones, etc.) near the thermostat?  
There are no cordless phones or baby monitors near the thermostat.  However, there is a microwave about 3m away.  There are two brick walls in the way as well.  The microwave was bought this year, (before the Nest was installed) so it will be compliant with the relevant Electromagnetic Compatibility legislation.  The Nest still cannot connect to the network even when the microwave is switched off.

5. What’s the make and model of your router?
In case you are not located in the UK, Virgin Media is a large supplier of online services to domestic dwellings.  They supply the router, which I have explained in answer 3.  It is probably made by a large manufacturer making such devices
Also please try these steps as well:
1. Reset the thermostat's network - Settings and then Reset and then Network 
Done - still not working 
2. Reset the thermostat to default settings - Settings and then Reset and then Reset All Settings

Done - still not working.  When the thermostat started up and the setup sequence started, I went to network setup. No networks were found so I had to input the network name into the Nest.  Should a list of available networks appear?  My iPhone picks up 4.  I can send photos if required 

[LarisaL]

Thank you so much for your detailed response. I just sent you an email with some information, please reply to the email with the information asked. 

[UanaC]

Hello there! Just checking, did you see my colleague's previous message?

[LarisaL]

Hey there, I haven't heard from you in a while so I'll be locking this thread. If you have any new issues, updates or just a discussion topic, feel free to start a new thread in the community. Thanks, Larisa