On your Nest Protect app,
Tap the Settings icon .
Scroll down and tap the option 'Nest Protect'
Tap ‘Spoken language’
Select the language you’d like to use
Nest Protect will automatically download the chosen language. Nest starts speaking the selected language within 24 hours from changing.
On the other hand, if you need your Nest Protect to download the new language right away, you will do the following.
Press the button on your Nest Protect once. It will read "Ready in the [room name]. Press to test."
Again, long press the button until you hear a bell chime. Protect will read "Checking the network." Now release the button.
The spoken language on your Protect will be updated in a few minutes.