Kids OK with adultArduino NanoLevel 2/3
Touchless Tap Saver
Water runs only while your hands are under the tap, so no tap is left running.

Kids OK, with an adult
DIY project. Children must build this only with an adult (16+ years) beside them at all times. Not suitable for children under 8 years.
The 12V valve and plumbing must be fitted by the adult.
Strictly follow the description given with this video.
Video
The video link will be added here soon.
How it works
- The IR sensor clipped to the spout sees your hands (its output goes LOW).
- The Nano switches the relay on.
- The relay opens the 12V solenoid valve and water flows.
- Hands away: the valve closes within a second.
Parts you need
- Arduino Nano× 1Buy
- IR obstacle sensor× 1Buy
- 5V relay module× 1Buy
- 12V ½" normally-closed solenoid valve× 1Buy
- 12V adapter× 1Buy
- 1N4007 diode× 1Buy
Kit for this projectPrice on request
Get the kitWiring

PowerGroundSignal
| # | From | Connect to |
|---|---|---|
| 1 Signal | IR OUT | Nano A0 |
| 2 Power | IR VCC | Nano 5V |
| 3 Ground | IR GND | Nano GND |
| 4 Signal | Relay IN | Nano A1 |
| 5 Power | Relay VCC | Nano 5V |
| 6 Ground | Relay GND | Nano GND |
| 7 Power | 12V + | Relay COM |
| 8 Signal | Relay NO | Valve T1 |
| 9 Ground | Valve T2 | 12V − |
| 10 Signal | 1N4007 diode | Across the valve coil |
3D print files
- tap_sensor_clip.stlPETG · 0.2 mmLink at launch
- relay_box.stlPETG · 0.2 mmLink at launch
Code
The tested Arduino / ESP32 code for this project will be posted here, ready to copy.