NEST thermostat lost iPhone connection.

[KC2SC]

Hi, I have always had my iPhone connected to my Nest thermostat. Somehow I have lost this facility. 
I have the added issue of my old e mail address dost function.

tried to Add a product to the Nest app but can’t get past the page that asks for the last 4 digits on my thermostat, I know them but the page only lets me tap "show me how" but OK, got it doesn’t take me any further. I know the 6 digits on the back of the thermostat (the scan Q code doesn’t get me anywhere)

I can access the thermostat via my iPad but that’s no use when I don’t have WIFI or when "mobile"

can somebody help please.

[David_K · Accepted solution]

First check which model of thermostat you have:
How to tell which Nest thermostat you have - Google Nest Help

Nest Thermostat (2020), Nest Learning Thermostat (4th gen)
Setup these models using the Google Home app. The QR code and setup key are physically printed on the back of the thermostat for Nest Thermostat (2020) and will be displayed on screen for Nest Learning Thermostat (4th gen). Follow these steps: Get started with your Nest Thermostat - Google Nest Help

Nest Thermostat E, Nest Learning Thermostat (1st, 2nd, 3rd gen)
Setup these models using the Nest app. The QR code and setup key are in the settings on the thermostat itself and are not printed on the device. Follow these steps: Add your Nest thermostat to the Nest app - Google Nest Help

[David_K]

Not to worry, try these steps:

1. On the thermostat itself, press it to open the quick view menu and tap the Settings cog.
2. Go to Reset, then choose Account connection. If you don't see this option, you'll need to select All settings instead.
3. Login to the Nest app on your iPhone using the "Sign in with Google" button. If you don't have a Google account, you'll need to create one.
4. Once logged into the app, on the Nest app home screen, tap the Settings cog.
5. Tap Add product. The app will switch to a camera view to scan the thermostat’s QR code.
6. On the thermostat, press it to open the quick view menu and tap the Settings cog.
7. Turn the ring to select Nest app and press to open it.
8. Select QR code. Your thermostat will show you a unique QR code to scan with the app. If it doesn't, tap Continue without scanning in the app and select Get entry key on your thermostat instead.
9. Follow the remaining steps in the Nest app.

[KC2SC]

Hi David, tried this but no Q code displayed and can’t find a entry key.

[David_K]

The steps above are specifically for Nest Learning Thermostat (1st - 3rd gen).

First check which model of thermostat you have:
How to tell which Nest thermostat you have - Google Nest Help

Nest Thermostat (2020), Nest Learning Thermostat (4th gen)
Setup these models using the Google Home app. The QR code and setup key are physically printed on the back of the thermostat for Nest Thermostat (2020) and will be displayed on screen for Nest Learning Thermostat (4th gen). Follow these steps: Get started with your Nest Thermostat - Google Nest Help

Nest Thermostat E, Nest Learning Thermostat (1st, 2nd, 3rd gen)
Setup these models using the Nest app. The QR code and setup key are in the settings on the thermostat itself and are not printed on the device. Follow these steps: Add your Nest thermostat to the Nest app - Google Nest Help

[KC2SC]

Thanks David, will check this out as I thought I had the 3rd generation learning  one (with heat link)  

[LewLips]

How to I find the entry key. It does not appear on my device. 

[David_K · Accepted solution]

First check which model of thermostat you have:
How to tell which Nest thermostat you have - Google Nest Help

Nest Thermostat (2020), Nest Learning Thermostat (4th gen)
Setup these models using the Google Home app. The QR code and setup key are physically printed on the back of the thermostat for Nest Thermostat (2020) and will be displayed on screen for Nest Learning Thermostat (4th gen). Follow these steps: Get started with your Nest Thermostat - Google Nest Help

Nest Thermostat E, Nest Learning Thermostat (1st, 2nd, 3rd gen)
Setup these models using the Nest app. The QR code and setup key are in the settings on the thermostat itself and are not printed on the device. Follow these steps: Add your Nest thermostat to the Nest app - Google Nest Help

[KC2SC · Accepted solution]

Just to say, thanks David. I checked and did have the right thermostat but still couldn’t sort, so phoned Nest. It was a Sunday but they were there (08081692307) the guy was excellent and patient and using some clever access tech’ to my phones camera walked me through the process.

All now ok and a relief to have phone access again. Regards Keith 

[StuB71]

Worked for me. Thanks David.