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I don’t know what it is about the filter on our washing machine, but the last two times I’ve cleaned it out and reinstalled it, I haven’t done it correctly. Not knowing that, I’ve walked away after starting a load, which has led to quite a mess. Having to drag out both my wet vac and carpet cleaner more than once was enough, so I installed the Shelly Flood Gen 4 in our basement laundry closet.
Whether you’ve dealt with a similar issue or want a device that alerts you immediately to a plumbing problem while you’re away, this smart leak detector has got you covered.
Key Takeaways
- Extended leak detection coverage. The Shelly Flood Gen4 features a 2-meter sensor cable, expandable up to 150 meters, for comprehensive moisture detection.
- Dual detection modes. Offers Flood Detection for indoor use and Rain Detection for outdoor use, with phone alerts and smart device integration.
- Smart home compatibility. Supports Wi-Fi, Bluetooth, Zigbee, and Matter, integrating with systems like Apple HomeKit and Google Home.
- Battery-powered reliability. Runs on four AA batteries, ensuring operation during power outages, with adjustable power modes for extended battery life.
Bottom line: The Shelly Flood Gen4 provides reliable, extensive leak detection with smart home integration and battery-powered assurance.
Best Overall Leak Detector
Shelly Flood Gen4 Smart Water Leak Detector
Rating: 4.8/5
Buy at Amazon Buy at The Home Depot Buy at Best BuyWhat We Like
- Loud alarm and reliable app alerts
- Smaller than a cell phone; fits almost anywhere
- Can link multiple cables to increase coverage
- Warning beep when battery life falls below 20 percent
What We Don’t Like
- Not fully waterproof
- Needs integration for automated shutoffs
Product Specs
- Power source: 4 AA batteries
- Alarm type: Audible, measured at 65 decibels; app notifications
- Waterproof: Sensing cord only; main hub is not
Coverage and Detection Modes
Unlike standard water sensors that only sound an alarm if liquid touches a specific spot, the Flood Gen4 has a 2-meter (about 6.5 feet) leak sensor cable that detects moisture along its entire length. That allowed me to position the main hub high enough to keep it out of water (it’s not fully waterproof), while winding the long cord directly under my water valves and along the front of my washer where the filter door is located. If you’re looking to get behind a vanity, fridge, or dishwasher with the Flood Gen4, you can link multiple sensing cables together to cover up to 150 meters (almost 500 feet).
For the sensor itself, you can choose between two modes depending on what you’re using it for. Flood Detection Mode is for indoor use, and it automatically triggers the unit’s audible alarm and sends alerts to your phone the instant it detects water. Rain Detection Mode is for outdoor use, and while it silences the sound of the alarm so you don’t annoy your neighbors, it still sends notifications to your phone. By pairing Rain Detection Mode with your other smart devices, you can perform actions like rolling up a motorized awning in a storm to protect it from damage.
Compatibility, Automation, and Power
The Shelly leak detector supports Wi-Fi, Bluetooth, Zigbee, and Matter, which means you can integrate it into almost any existing smart home system, including Apple HomeKit, Google Home, and Samsung SmartThings. If you then link the sensor with inline switches or smart valves, you can set up useful safety responses like cutting power to a leaking dishwasher or shutting off your main water valve if moisture is detected.
When I first started testing the Flood Gen4, I didn’t understand why a unit that you tuck behind an appliance or leave unattended at a cabin or vacation property would run on batteries rather than plugging into a wall outlet. But given that a major leak or sudden flooding can easily trip a breaker and kill a wall-powered device, relying on battery power is a much better way to ensure continuous operation. Also, you can monitor the remaining power of the Flood Gen4’s four AA batteries in the app, and if it falls below 20 percent, you’ll not onlyl receive a notification but the unit will also periodically emit a brief beep.
If desired, you can decrease the detector’s power consumption through the Flood Gen4’s three alarm modes: Intense, Normal, and Economic. Switching to Economic stretches the battery life up to 2 years by turning off the audible alarm and adjusting reporting frequency from every 30 seconds in Intense Mode to only when a state change occurs.
Where to Buy
Photo: Michelle Larson for BobVila.com
