The YoLink Water Leak Sensor 4 is a battery leak sensor with a loud built-in alarm that can close a YoLink valve on its own, even without the internet.
It senses water two ways: two contacts in the cupped top catch a drip from above, and four underneath catch water pooling on the floor. A 105 dB alarm sounds on the sensor itself, and it also warns when the room gets cold enough to freeze a pipe.
It runs on two AAA batteries, which YoLink rates at more than five years, and the case is rated IP66, so the sensor does not need replacing after it gets wet.
It needs a YoLink hub such as the SpeakerHub, and Home Assistant’s YoLink integration reaches it through the YoLink cloud. Paired directly with a YoLink valve controller, it closes the valve on a leak even without the internet. On Amazon it comes in a 3-pack with the SpeakerHub.
Recipes using this device
Leak Auto Shutoff
Installs a Home Assistant automation that closes your water shutoff valve the instant a leak sensor goes wet, so a burst hose or a failed valve stops flooding within seconds. Add a smart plug to cut the appliance, a siren, and a speaker.
Water Leak Alert
Installs a Home Assistant automation that watches every water leak sensor you select and alerts you the moment one goes wet, naming the spot so you know where to look. Add a speaker and the same warning is announced out loud.