If the battery tab has been removed from the device, the LED indicator for the ZSE42 Water Leak Sensor should flash for around 10 seconds, or whenever the Z-Wave button is clicked. Is the sensor unresponsive and the LED is not flashing?

To begin, double check that the battery is inserted in the sensor correctly, as depicted by the positive / negative pole marks. You may need to adjust the battery slightly to get the sensor responsive.

If the sensor still does not respond, please try a fresh lithium non-rechargeable battery to rule out any power-related issues. If the LED's flash successfully and the sensor responds well with the new battery, the issue was likely caused by a drained battery.

Once you have tried the processes above and the LED is still not responsive, please try clicking the Z-Wave button 3 times as quickly as possible to force inclusion/exclusion mode in case you missed when it first flashed.

If there is some LED activity, but the sensor is not responsive during wake-up, inclusion, or exclusion, you can try a factory reset for the device. This is a hard reset that will erase all previous activity from the device. Follow the instructions here to factory reset the ZSE42.

Please let us know if this does not solve the issue for you; our team is happy to help!