I have for some time had Smartthings routines changing the state of my Nest 3rd Gen thermostat. E.g ‘when door sensor is open, set thermostat to ECO’. However these routines stopped working last week and I’ve been unable to establish why.
The ST iOS app correctly reports the current state of the Nest, but any temperature or state changes made in the ST app do not now have any impact on the Nest.
I can see the routines are being triggered and are reported in the history of the ST app. It appears the info flow is one way - Nest to ST - but not working from ST to Nest.
Fixes tried: deleted and reinstalled both Nest and ST apps. Unlinked the Nest and ST accounts and created new services link.
Equipment: Nest 3rd Gen learning thermostat, ST Hub (2018) with latest firmware.
Google support are currently washing their hands of it. Stating they have ‘no protocols to provide support to the ST hub’ and claiming no resource assigned to managing the integration service between Google and ST.
ST support are checking on logs etc, so still waiting on a response. Further testing on my end suggests this is not a problem with the routines, but is a more fundamental breakdown in the link between ST and the thermostat. If I open the thermostat device in the ST app and make any changes to the temp or mode, the ST app shows the new state, but nothing happens at the Nest end.
the current official Google Nest integration does not use Works with Nest. That program was shut down to new members a few years ago but existing users were able to continue using it until it is shut down (your email). No current integrations exist for the Works with Nest as it was only used with Groovy. The old community developed Nest Manager was the only one I remember using it.
I’ve done some further testing of the comms between the ST app and the thermometer. The main issue seems to be with putting the Nest thermometer into Eco mode. Commands sent from the ST app to change mode to Heat and Off appear to work, albeit with occasional delays and sometime a ‘server or network error’ message. However all attempts to change the mode to Eco fail.
Likewise any attempt to alter the target temperature fails.
I’ve advised ST support and have for the time being adjusted my routines to turn off the thermostat when a door is opened rather than go to Eco mode (and back to Heat when the door closes) and they seem to be working so far.
ST support have investigated and found that the tokens from the Nest thermostat are expiring, causing the integration to fail. Having gone back to Google support with this, they have continued to wash their hands of the issue, in short saying we haven’t changed anything so it can’t be our problem.
At this stage it looks like the end of the line and I’ll have to accept a reduced level of functionality until I replace the thermostat with a non-Google one.
As @Patrick888 says, the problem is with the eco mode. I have noticed that if I turn it on using smarthings, then I cannot control the temp ans modes anymore. The only way is to go to the nest app, select on or off and then it works again. The issue lies when you set a routine in which case it wouldn’t work.