Third Reality Water Leak Sensor

Quick verdict

Cheap, simple, and it works — that's all you really need from a water leak sensor. Scatter a few under sinks, behind the washing machine, and near the water heater. Zigbee means it runs fully local through Home Assistant with no cloud or subscription.

Standout: Cheap and reliable Zigbee water leak detection — scatter several around your home for peace of mind.

Last checked: 2026-03-22

Compatibility snapshot

Why it stands out

• very affordable water leak detection
• solid Zigbee compatibility with zigbee2mqtt and ZHA
• long battery life with CR2 battery

Reasons to hesitate

• basic feature set — detection only, no water shutoff valve control
• requires a Zigbee coordinator for Home Assistant use

Best for

• budget water leak monitoring under sinks, water heaters, and washing machines
• Zigbee Home Assistant setups needing reliable leak alerts

Avoid if

• you want an all-in-one leak detection plus automatic shutoff system
• you have no Zigbee coordinator

Privacy and local-control notes

Pure Zigbee sensor with no cloud dependency. Fully local operation through zigbee2mqtt or ZHA.

Home Assistant support: supported · integration path: zigbee2mqtt / ZHA.

Buying reality check

Price notes: Very budget-friendly. Buy multiples to cover every leak-prone spot.

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