This week, I added a bunch of Aqara Water Leak Sensors to my home assistant setup.
Pairing the Aqara Water Leak Sensor with Home Assistant
The first hurdle was how to trigger pairing mode of the Aqara Water Leak Sensor. The manual only describes this process for their own hub / app combination. I run Home Assistant with a ZigBee stick and would rather not add a hub for each device maker. Turns our the solution is simple: Press on the top of the sensor till a blue light just below the water drop starts flashing. This switches the device into pairing mode. I was able to pair the sensor as usual in the Zigbee panel of Home Assistant.
Rename the Sensors
The names chosen for the actual sensor entities were a bit random and hard to
parse for me. Hence, I renamed the sensor entities to something like
binary_sensor.water_leak_detector_kitchen_sink in the Home Assistant UI. This
makes subsequent references to them from YAML code a lot easier.
Test the sensor
When initially testing the sensor, they failed to detect water even when submerged for a few minutes. When I repeated the same test a few minutes later, they detected water in much smaller volume instantly. Not sure why this is. Could be that the sensor calibrates itself after startup and needs some time to do so.
Group the sensors
When thinking about water leak notification, I don’t actually care which sensor
is detecting a leak. I can look that up in the Home Assistant UI whenever I
want. Hence, I grouped the devices into one meta sensor using the
Binary Sensor Group platform like so in my
binary_sensor: - platform: group name: Water Leak device_class: moisture entities: - binary_sensor.water_leak_detector_kitchen_sink - binary_sensor.water_leak_detector_main_bath_sink_right - binary_sensor.water_leak_detector_main_bath_sink_left - binary_sensor.water_leak_detector_main_bath_toilet - binary_sensor.water_leak_detector_utility_room - binary_sensor.water_leak_detector_washing_machine
This creates a new sensor named
Water Leak with the entity id
binary_sensor.water_leak. This sensor will detect a leak whenever any one of
the grouped sensors does so.
Setup an Alert
This new group then allows me to send alerts to my phone using the Alert platform like so:
alert: water_leak: name: Water leak detected message: Water leak detected done_message: Water leak no longer detected entity_id: binary_sensor.water_leak state: "on" repeat: 1 notifiers: - mobile_app_pixel_4_xl
This will send a notification to my phone (entity
a minute while a leak is detected. It will send the “all clear” notification
when the leak is no longer detected. This might be a bit excessive, but better
safe than sorry :-).