Troubleshoot wired Nest Protect power problems

Wired Google Nest Protects come with long-life backup batteries, so they'll keep on working when you need the most. If your wired Nest Protect stops receiving power from the building's electrical wiring, it will automatically switch to backup battery power.

Even when it’s running off the backup batteries, your Nest Protect (Wired) will stay connected to other Nest Protects in your home. It will continue to monitor smoke and carbon monoxide conditions and alert you in the event of an emergency or Heads Up alarm. It will also continue to send notifications to the Nest app in the event of an alarm as long as the Wi-Fi network is still working.

You'll know your Nest Protect isn't receiving power when the small green light at the top of the Nest button has switched off.

Receiving power

Not receiving power

nest protect receiving power

nest protect not receiving power

app protect home

app protect alert no power

You'll also get an alert on the Nest app
telling you that the power is out.

nest protect app notification

Troubleshoot wired Nest Protect power problems

If you receive a power out notification from the Nest app and you see that the green power light on a wired Nest Protect is out, try these two troubleshooting steps in order.

If you had a professional install your Nest Protects, contact them to fix any trouble you’re having. We strongly recommend that you have a professional installer diagnose wiring issues. A trained professional knows how to safely deal with high-voltage equipment and ensure proper connection for all wires. You can always find a local proinstaller.

  • Check your breaker box
    When power goes out to only part of your house, one or more
    switches on the breaker box may not be turned on. Sometimes
    these switches can be tricky because they’re difficult to push.
    You may think you flipped a switch back on, but it didn’t flip all
    the way. Try flipping the switches off and on again. If your Nest
    Protect’s small green light illuminates, after flipping a fuse
    switch, you’ll know that was the problem.
breaker box with text


  • Check your wiring
    If one wired Nest Protect is the only thing in your house that’s not receiving power, it’s likely that there’s a problem with the wiring. While wiring issues usually crop up during or right after installation, wires can sometimes become detached later, especially if the connections weren’t properly terminated with a wire connector or connector block.

Here are steps to take for checking your Nest Protect wiring. Please refer to your Nest Protect User Guide for more wiring details.

1) Turn off the power

Protect yourself and avoid blowing a fuse.
Switch off the correct circuit breaker or
remove the correct fuse from the fuse box.
Double check that any lights, appliances or
other electronics connected to the same
circuit are off.

breaker box with warning sign

2) Remove your Nest Protect

Remove your Nest Protect by gently twisting
it counter-clockwise.

remove protect image

3) Check the connector

Make sure the connector is fully inserted into
the back of Nest Protect. If it wasn’t, try
turning the circuit breaker switch back on. If
the small green light still doesn’t illuminate,
turn the circuit switch off again and try step

protect connector


4) Check the wiring

Check that the power wire and neutral wire connections are connected to the right wires on Nest Protect’s connector. Refer to your Nest Protect User’s Guide for more details.

There must be solid contact between the power wires. Make sure that all wire connections are capped with a wire connector or connector block that has been attached securely.

5) Turn the power back on

Flip the circuit breaker switch back on and
check to see if the Protect’s small green light
is on. The status in the Nest app may take a
few minutes to change, so it’s best to check
the light.

If your Nest Protect still hasn’t turned back
on, contact your professional installer or give
us a call. We’re here to help.

breaker box with warning sign


* Different countries use different wiring standards, and the exact voltage of your Nest Protect (Wired) depends on where you purchased it. For example, a Nest Protect sold in the United States includes components for 120V wires, whereas a Nest Protect sold in Europe includes components for 220V-240V wires.

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