First Alert L1 WiFi Water Leak and Freeze Detector
Home Protection, Water Damage Prevention, Leak Detection, Freeze Protection, Humidity Monitoring, Sump Pump & Appliance Monitoring
Overview
The First Alert L1 is a battery-powered Wi-Fi water leak and freeze detector from Resideo that warns you instantly via push notification, email, a loud 100 dB alarm, and LED lights when it senses water, freezing temperatures, or out-of-range humidity. It comes with a 5-foot cable sensor that detects water along its whole length and can be extended to 500 feet, plus on-device sensing contacts for floor placement. With no hub required, direct 2.4GHz Wi-Fi setup, and array of app-based alerts and trend tracking, it is an easy-to-install, expandable early-warning system for sinks, water heaters, sump pumps, washing machines, and basements.
Key Highlights
- Wi-Fi smart leak and freeze detector that sends push and email alerts plus a 100 dB alarm with LED lights when a leak, freezing temperature, or out-of-range humidity is detected
- Includes a 5-foot cable sensor that detects water along its entire length, plus on-device sensing contacts; add extension cables to reach up to 500 feet of coverage
- Built-in temperature and humidity sensors deliver trend tracking in the First Alert app so you can spot freezing pipes and humidity issues before they cause damage
- Fully reusable and easy to install: powered by 2 AA batteries, requires no hub, and can be wall-mounted or placed on the floor; dries and resets after a leak
- Part of an expandable system: pair multiple L1 detectors together or combine with the Resideo L5 WiFi shutoff valve for automatic water shutoff
Video
Technical Specifications
| Brand | First Alert |
|---|---|
| Model | First Alert L1 WiFi Water Leak and Freeze Detector |
| Sensor Type | On-device water sensing contacts plus included 5-foot cable sensor that detects water along its entire length; cable jack connection, wall or floor placement with mounting keyhole |
| Connectivity | Wi-Fi 2.4GHz (ISM band) direct connection, First Alert app (iOS / Android), no extra hub required; includes on-device LED status lights and 100 dB alarm |
| Battery | Powered by 2 AA alkaline batteries (included) |
| Alarm Volume | 100 dB alarm plus LED status lights |
| App Support | First Alert app: mobile push notifications, email alerts, assign additional users to receive alerts, temperature and humidity monitoring with trend tracking |
| Smart Home | No third-party integrations (no Alexa, Google, or HomeKit). Pairs with the Resideo L5 WiFi Water Leak Shutoff Valve to automatically shut off water on leak detection. No Matter/Thread support. |