How Nest Protect lets you know it's working

Nest Protect automatically runs a Self Test, where it checks its batteries and sensors every 200 seconds. Once a month, Nest Protect can also perform an automatic Sound Check to test its speaker and siren. And you can run a full Safety Check-Up at any time so you know your Nest Protects are interconnected and so you can listen to the speaker and siren for yourself.

Since smoke alarms are critical safety devices, it's important to know that they're working. But according to the US National Fire Protection Association, 9 out of 10 people don't test them as often as they should. That's why Nest Protect has two automatic tests: Self Test and Sound Check.

Self Test runs every 200 seconds. It checks the following:

  • Power
  • Smoke sensor
  • Carbon monoxide sensor
  • Wi-Fi

Learn about Self Test

Sound Check runs once a month. It verifies the following:

  • Speaker
  • Siren
  • Light ring

Note: Sound Check must be set to automatically run with the Nest app.

Learn about Sound Check

Nest Protect app: Everything OK image.


Check with the Nest app

The Nest app will show you the most recent information available about Nest Protect.

If everything is fine, your Nest Protects should be green in the Nest app.

If there is a problem, like low batteries, the Nest app will show you what's wrong and tell you what to do.

  • Battery-powered Protects check in once a day.
  • Wired 230 V Protects check in every 30 minutes.

Learn how to access your Nest Protect from the Nest app or the web

Look for Nightly Promise

When you turn out the lights for the night, Nest Protect will glow green briefly to show you that its smoke and CO sensors are working, and that it has enough power. That way it won't chirp in the middle of the night. We call this Nightly Promise.

  • If all Nest Protects in your home are connected to the app and one glows green, that means that they're all fine.*
  • If there's a problem with one of your Nest Protects, like a low battery, Nightly Promise will glow yellow. Nest Protect may also speak up to tell you what's wrong.

Learn about Nightly Promise

*All Protects in the home must be connected to the same account in the Nest app.

Run a Safety Check-Up

The US National Fire Protection Association recommends testing your alarms at least once a month. Safety Check-Up helps you easily run a thorough test of all your Nest Protects. The test lets you hear your Nest Protect's speaker and siren, so you know that your Protects are working. When you run the test, you should listen for the alarm to sound on each device.

If you run a Safety Check-Up, it can also help you and your family become more familiar with the lights and sounds of Protect, just in case of an actual alarm. What's more, you can run a Safety Check-Up whenever you like, so you don't have to wait for a monthly Sound Check.

You can run a Safety Check-Up via the Nest app for a 2nd-generation Nest Protect or press the Nest button on any Nest Protect. The test takes a few seconds to complete and is loud.

At the end of Safety Check-Up, the Nest app should let you know that everything works or if there's a problem, like low batteries, a sensor failure or if your alarm has expired.

Learn about Safety Check-Up

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