I have an european Nest Learning Thermostat 2nd generation and it is still running.
I would to know if the 3rd gen device is compatible with the 2nd gen heat link installing for controlling my boiler. I only need the wireless connectivity between the two devices.
Thank you in advance!
Regarding the 2nd Gen thermostat working with a 3rd Gen, the the answer is yes!
I think what you are saying is - you would like to keep the 2nd Gen Heat Link and upgrade to a 3rd Gen Display. Would that be correct?
The 2nd Gen Heat Link ONLY has heating and NO water control, but if that's all you need, not a problem. Combi boilers are fine with that setup.
You can pair the 3rd Gen display with a 2nd Gen Heat Link.
You will need a new Base Ring for the 3rd Gen display, as the 2nd Gen Base Ring does NOT fit the 3rd Gen display.
When fitted, just setup as ''Replace Heat Link'', and you should be good to go. You have to pair again, as it will not be a matched set anymore.
Again a simple answer, yes they will work together. Same as above really they use the same pairing, just the other way round.
You will not get the use of Hot Water with the 3rd generation Heat Link, as the thermostat does not support Hot Water. The only real reason for using a 3rd H/L with a 2nd Display, if your 2nd Gen H/L is faulty.