The system includes electric faucets and sensors that are placed in places where a pipe may leak, such as under a sink or bathtub. If water gets on the sensor, the controller sends a command to the electric faucet, which is shut off by a motor inside. When the system shuts off the water, it simultaneously emits sound and light signals. You will have to manually supply water to the apartment again after the cause has been eliminated.
You can set up the system so that it notifies you of a leak by phone. To do this, the control unit must be connected to Wi-Fi. And when the protection system shuts off the water, it will send a notification to the mobile application.
An electric faucet is installed after the inlet faucets to the apartment, before the meter. If you install the faucet after, it will not protect the apartment from leaks in the event of a meter failure.
Since the water inlet unit needs to be redesigned for the system, a plumber should do this. It is better to do this at the repair stage. On average, the protection system costs from 30,000 ₽, and installing it - from 3,000 ₽.
Leak sensors are placed so that they are not splashed during daily water procedures. It is a dubious pleasure to leave the bathroom soapy, because random splashes got on the sensor and the system shut off the water in the apartment. One of my customers even turned it off because of this. In his case, the controller did not provide wireless sensors that can be painlessly rearranged, and the wires were under the floor tiles. To replace them, it would be necessary to break the tiles and redo the repair.