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If you started using the Nest app after August 19, 2019, you’re already using a Google Account and don’t need to migrate. Once you set up your Thermostat on the Nest app using your migrated account it will automatically be linked on your Google Home speakers. However, if you're using the latest Thermostat (2020), you need to use the Google Home app in setting it up. Once your speaker and Thermostat are set up using the same Google Account and under the same home structure, you'll be able to control it using your speakers. Visit this page for more information.
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