Adults onlyESP32Level 2/3
Geyser Auto-OFF Timer
Press the button and the geyser runs for a set time, then switches itself off. Check it from your phone.
Adults only
Involves 230V mains and a high-power geyser.
Not for children. Build at your own risk.
A 10–13 A geyser is too much for a relay module, so the relay only switches the contactor coil. MCB, earth, a closed box and a licensed electrician are required.
Strictly follow the description given with this video.
Video
The video link will be added here soon.
How it works
- Pressing the button starts the timer.
- The ESP32 switches the relay, which energises the coil of a 25 A contactor.
- The contactor, not the relay, switches the 2–3 kW geyser.
- The phone page geyser.local shows the time left; at zero it switches off.
Parts you need
- 1-channel 5V relay module (HIGH-level trigger)× 1Buy
- ESP32 development board (30-pin)× 1Buy
- 25 A contactor with 230V coil× 1Buy
- Push button× 1Buy
- MCB + closed enclosure× 1Buy
Kit for this projectPrice on request
Get the kitWiring
PowerGroundSignal
| # | From | Connect to |
|---|---|---|
| 1 Signal | Relay IN | ESP32 D25 |
| 2 Power | Relay VCC | ESP32 VIN |
| 3 Ground | Relay GND | ESP32 GND |
| 4 Signal | Button | ESP32 D4 → GND |
| 5 Signal | Relay COM / NO | Contactor coil circuit (electrician) |
| 6 Signal | Contactor main contacts | Geyser supply (electrician) |
3D print files
This project has no 3D-printed parts.
Code
The tested Arduino / ESP32 code for this project will be posted here, ready to copy.