Inexpensive Water Leak Detection using a Dry Contact Input

When I installed my automated water shutoff valve, I used three of Smarthome's battery powered, wireless leak detectors. They work quite well and are simple and easy to install and setup without wires. There is a less expensive way to add leak detection, if you have dry contact inputs to your home automation system, such as the Insteon Smarthome I/O Lincs or the Smartenit EZIO series. You can purchase a spare Floodstop water sensor, pictured below:

Floodstop Water Sensor

The Floodstop water sensor is basically a simple circuit board with a series of intertwining contacts that don't make contact on the board. If water touches the board, it will allow current to flow between the two outputs. All you need to do is some wiring from this board to your dry contact into your automation system, set it up with a current source, and when current flows through the circuit it will change the state of your contact.