A02YYUW Waterproof Ultrasonic Sensor for Arduino / ESP32 / Home Assistant (IP67, 3~450cm, UART)

Looking for a waterproof distance sensor that doesn't sacrifice close-range accuracy? The A02YYUW is an enclosed, IP67-rated ultrasonic ranging module built for harsh environments. While standard exposed sensors fail quickly in humid conditions, and split-design sensors suffer from large dead zones, the A02YYUW delivers stable distance readings from 3cm to 450cm with a precise 1mm resolution. With 3.3V-5V logic tolerance and a standard 9600 bps UART interface, it wires directly to your microcontrollers—making it an excellent choice for liquid level monitoring and outdoor proximity detection.. The ranging module seamlessly integrates with Arduino, ESP32, Raspberry Pi, and enjoys support for ESPHome, making Home Assistant automations easier than ever.

Native ESPHome & Home Assistant Integration (UART Version)

Skip the complex C++ coding. The A02YYUW ultrasonic sensor has native platform support in ESPHome, making it dead-simple to pull water level metrics directly into your Home Assistant dashboard.

Maker Pro-Tip for Home Assistant: Because the ultrasonic sensor outputs data multiple times per second via its UART bus, raw data can fluctuate slightly. We highly recommend applying Sensor Filters (such as sliding_window_moving_average) in your ESPHome YAML configuration to smooth out the readings.

(Note: The official ESPHome component specifically supports this UART version of the A02YYUW. PWM and RS485 versions are not supported by the default integration.)

Pair this ultrasonic sensor with a low-power IoT board like the FireBeetle 2 ESP32-C6, and your DIY sump pump monitor or rain barrel tracker will be up and running in minutes.

A02YYUW Waterproof Ultrasonic Sensor compatible with ESPHome & HomeAssistant

True IP67 Waterproofing for Long-Term Stability

Humidity can ruin a project. Unlike sensors with exposed circuit boards (like the HC-SR04) or inconvenient split designs (JSN-SR04T), the A02YYUW ultrasonic distance sensor features a fully sealed, integrated body. Its IP67 waterproof rating means it can withstand dust, splashes, and even temporary submersion. This robust design ensures stable, reliable data output over the long term, making it the ideal choice for outdoor applications or continuous liquid level monitoring.

IP67 Waterproof A02YYUW Ultrasonic Sensor

Measure What Matters: The 3cm Ultra-Small Blind Spot Advantage

When monitoring a tank, every centimeter counts. The JSN-SR04T, has a massive 20cm blind spot, making it impossible to detect when a tank is nearly full.

The A02YYUW sonar sensor solves this with an industry-leading 3cm blind spot. This allows for accurate distance readings right up to the top, providing precise control over water levels and preventing overflows in automated systems.

A02YYUW Waterproof Ultrasonic Sensor features 3cm Blind Spot

Beam Directionalities Diagram

Maker-Friendly & Versatile for All Projects

This ultrasonic distance detection sensor is designed with the DIY community in mind. It operates on a flexible 3.3V-5V power supply and communicates via a standard UART serial port, making it incredibly easy to connect to any microcontroller. It's fully compatible with popular platforms like Arduino, ESP32, and Raspberry Pi. A connection cable is included, allowing projects to be up and running in minutes, not hours.

A02YYUW Waterproof Ultrasonic Sensor compatible with Arduino / ESP32 / Raspberry Pi