Chosen Solution
Hi Folks, my nest wouldn’t connect to the heatlink. I’d been on to nest support and they said the system needs to be replaced. Apart from checking version numbers there was no “nest magic” suggested by the support rep, over and above what I’d already tried.
Searching the web I came across an article that included how to re-boot the thermostat. The nest techie didn’t suggest this. I gave it a try and it’s all working again. You can’t beat a good old “switch it off, switch it on” can you? The reboot is achieved by pushing the display in for about 20 seconds. Apologies if you know this already. Cheers Jim
Thanks to those who posed here (DandM Dame and mas.sheraton) I have managed to get my Nest 3rd Gen working. My problem:- failure to establish connection between heatlink and thermostat (H72 error). This persisted despite many reboots, units being next to each other etc. Solution : Use the wired setup, connecting T1 and T2 of heatlink and thermostat) and completed the setup steps without a wireless connection. This allowed access to main menu and the factory reset option. Started working immediately for me after this, would recommend you also do a heatlink reset (hold button for 15 sec) just before factory reset on the thermostat.
Usually there is a long troubleshooting section available inside owner’s manual for Nest tstats. You can find your model here. You should see some error code if it can’t connect. To understand the message just open the manual on troubleshooting page. The reason usually very simple: some wire not connected.
