I've just bought a brand new Nest Thermostat E, managed to connect the actual thermostat, but no luck with heatlink. It came up with error code TH030. An internet search came back without much useful information. I have tried the following steps but still failed to connect:
1. Turn off all the devices in the room that are using Wifi or Bluetooth. 2. Reset the thermostat by pressing it quickly 2 times and then press and hold the display for 5 seconds. 3. Reset the Heat Link by pressing its button 1 time to wake it up and then press and hold for 15 seconds. 4. Power cycle your phone. 5. Open the Nest app and create a new home structure. 6. Enable airplane mode on your device and then enable your Bluetooth and Wifi. 7. Add the thermostat to your new home ( you can also try to add it without scanning the QR code ).
All these steps have been done right beside the router. Any help will be greatly appreciated, otherwise I think I'd return it and go for another brand instead.