Nest Support

Questions about Nest Learning Thermostat or Nest Protect: Smoke + CO alarm? We've got answers, videos, and plenty of resources to help you out.

What’s the difference between Heads-Up and Emergency Alarms?

Before turning on a loud, emergency alarm, Nest Protect gives you a gentle Heads-Up as an early warning. Nest Protect lights up yellow and speaks with a human voice. It tells you where smoke is or when carbon monoxide levels are rising. If it’s just a nuisance alarm, like burning popcorn, Heads-Up allows you to silence Nest Protect.

The sound of smoke alarms is designed to be piercing, unavoidable, scary. But we hear smoke alarms cry wolf so often that the alarm isn’t doing its job anymore. When it goes off, we’re not scared—we’re annoyed. And we take the batteries out. This irritating sound could mean there’s an emergency or it could mean you’ve burned the dinner.

This frustration puts all of us in danger. According to the National Fire Protection Association (NFPA), in 73% of U.S. homes that experienced a fire, the alarm didn't go off because the batteries were dead, disconnected or removed.

This is why we created a new kind of alarm. If Nest Protect detects low levels of smoke, it gives you a gentle Heads-Up as an early warning. If the situation gets worse, Nest Protect sounds the Emergency Alarm.

What is a Heads-Up?

Nest Protect gives you an early warning that smoke or carbon monoxide (CO) levels are rising. When Nest Protect senses smoke or carbon monoxide below emergency levels, it pulses yellow and tells you what’s happening: “Heads-Up: there’s smoke in the kid’s bedroom.” It will also send you a mobile notification on your smartphone or tablet.

Can I silence a Heads-Up?

Heads-Up voice alerts can be silenced by pressing the Nest button. After silencing, this will give you time to identify and address the problem without a screeching alarm going off. Always make sure you are safe before silencing Nest Protect.

What is an Emergency Alarm?

When smoke or carbon monoxide (CO) reach emergency levels, Nest Protect pulses red, makes a loud sound, and tells you what and where the emergency is. “Emergency: there’s carbon monoxide in the basement. Move to fresh air.” Nest Protect will also send you a mobile notification.

Below are some differences between Heads-Up and Emergency Alarms:

Heads-Up Emergency Alarms

When will the alarm sound?

At low levels of smoke and carbon monoxide (CO).

At emergency levels of smoke and carbon monoxide.

What will I hear?

During a Heads-Up, Nest Protect will tell you what and where the danger is: “Heads-Up! There’s smoke in the kids’ bedroom.” or “Heads-Up! there’s carbon monoxide in the kids’ bedroom.”

During an Emergency Alarm, Nest Protect will make a loud sound, and tell you what and where the emergency is. “Emergency: there’s smoke in the basement.” or “Emergency: there’s carbon monoxide in the basement. Move to fresh air.”

What color lights will I see on Nest Protect?

Yellow light

Red light

Why don’t all events get a Heads-Up?

Sometimes you may hear an Emergency Alarm without first getting a Heads-Up. This means that emergency levels of smoke or carbon monoxide (CO) have occurred extremely quickly and Nest Protect must sound the Emergency Alarm.

Nest Protect is first and foremost a safety device. It will monitor and sense the level of smoke and carbon monoxide in your home, then give you the appropriate Heads-Up or Emergency Alarm.

Can I get two Heads-Up in a row, one for smoke and one for carbon monoxide?

In very specific conditions it is possible to receive more than one Heads-Up. If Nest Protect simultaneously senses both smoke and carbon monoxide levels below emergency levels, you will hear Heads-Up twice.

Will I get a Heads-Up after an Emergency Alarm?

In rare circumstances, if there is still smoke or carbon monoxide in the room, Nest Protect may issue another Heads-Up or an alarm as needed.

Can I disable Head-Up and Emergency Alarms?

You can disable Heads-Up for smoke and carbon monoxide from your Nest app or the Web. For your own safety, Emergency Alarms cannot be disabled since they detect dangerous situations that require you to move quickly to safety.

Will I still get nuisance alarms?

Since Nest Protect is an advanced safety device, and we designed the Heads-Up feature to decrease the nuisance of unwanted alarms without affecting your comfort or safety. Nuisance alarms occur when there’s a source of smoke — like burning toast — that you know about and have under control.

For low levels of smoke or carbon monoxide, Nest Protect will alert you using Heads-Up. Nest Protect knows what smoke is, but not what is burning (like toast). If the smoke level rises, Nest Protect will sound a loud, piercing alarm.