Step one is to upload a clear, high resolution photograph of the circuit board. From there we’d be able to make educated guesses about what might be connected to which pins, and what might be involved in flashing it. Depending on how it’s designed, it might be easy, difficult or impossible to assess from images.
- Flashing it with Esphome
- Mapping the solenoid outputs to switches
- Controlling the two line display (optional)
- Receiving input from the keypad (optional)
It’s also possible (though unnecessary and therefore unlikely) that the ESP isn’t the primary controller, in which case the whole thing would be beyond the scope of this forum.
If you can somehow contact the original developer, they might be nice enough to offer you some hints about the device.