For this project, I repurposed a 4D Systems 4.3” touchscreen display with an integrated ESP32-S3 processor. I originally bought it for a previous ground-penetrating radar project, but ended up using an Android app instead of a display for that build.

In this case, I felt having a local display was much more practical—it clearly shows what’s going on during the brewing process and makes the system easier to use without relying on a phone or external device.

The ESP32-S3 is a powerful little chip with built-in Wi-Fi and BLE, so adding remote control via an Android app is still a possibility for the future. But for now, the touchscreen gives me all the interaction I need.

GEN4-ESP32-43 CT mounted on a 3d printed enclosure 

All parts of the enclosure with the PCB mounted inside

And this is the how it looks assembled.

In addition to the 4D Systems controller, there's a support PCB that includes the following circuits:

• 24V to 5V switching regulator

• Buzzer driver

• PWM motor driver

• PWM output for controlling the IKEA induction heater

• Analog interface for the PT1000 temperature sensor

I prefer to etch my PCBs at home, so to keep things simple, all components and signal traces are placed on one side, with the other side used solely as a ground plane.

This is the complete schematic :

The system is powered by an external 24V, 750mA power adapter.