Google Nest Protect 2nd Gen Wired

Model details

Additional useful information

Use this Scanual guide to identify Google Nest Protect 2nd Gen Wired, follow official setup and reset guidance, and match power, radio, mounting, hub, and regional accessories to model Nest Protect 2nd Gen Wired.

Google Nest Protect second-generation wired model uses a 120V AC harness with three specified lithium AA backup cells, smoke and CO sensing, app alerts, and ten-year replacement life.

Setup: De-energize the branch circuit, verify the 120V regional model, install its supplied harness and wired backplate to code, restore power, add it in the Nest app, and test the alarm.

Reset: Hold the Nest button through the spoken version and countdown until reset completes. Re-onboarding does not replace electrical testing, preserve history, or change the printed ten-year expiry.

Troubleshooting: For power or chirp warnings, inspect breaker, harness seating, three L91 backup cells, expiry, dust, and app diagnostics. A failed manual alarm test or expired sensor requires complete replacement.

Compatibility and ecosystem boundary: This 120V model is not the six-cell battery version and does not use a traditional alarm interconnect wire. Harness, backplate, voltage, certification, and electrician requirements vary by region.

Maintenance and accessory matching: Test and clean on the prescribed schedule, replace all three backup cells with L91 units, and replace the complete alarm at expiry. Electrical work must follow local fire and wiring codes.

Published checkpoints: Generation: second-generation Nest Protect wired version. Primary power: 120V AC through the supplied model-specific harness. Backup power: three Energizer Ultimate Lithium L91 AA cells. Smoke sensing: split-spectrum photoelectric design. Carbon monoxide: electrochemical sensor. Additional sensing: occupancy, ambient light, temperature, and humidity support features. Wireless: 2.4GHz Wi-Fi for app services. Interconnect: Thread-based wireless interconnect, not a legacy interconnect conductor. Alarm: voice warnings and 85dB horn. Lifecycle: replace the entire alarm ten years after manufacture. Installation: electrical box and branch-circuit work follow local code. Reset: hold the Nest button through spoken countdown and re-onboard.

• Additional sensing: occupancy, ambient light, temperature, and humidity support features
• Wireless: 2.4GHz Wi-Fi for app services
• Interconnect: Thread-based wireless interconnect, not a legacy interconnect conductor
• Alarm: voice warnings and 85dB horn
• Lifecycle: replace the entire alarm ten years after manufacture
• Installation: electrical box and branch-circuit work follow local code
• Reset: hold the Nest button through spoken countdown and re-onboard