Instructions | Quick n' Dirty Freezer Door Alarm

1

Connect one of the reed switch's terminals to a GPIO pin on the ESP-32

You should make sure the pin matches the number specified as `SWITCH_PIN` in the Arduino code.
2

Connect the other reed switch terminal to the ESP-32's ground
3

Load the ESP-32 Arduino code onto the board

code: https://gist.github.com/dupontgu/8efcca2611103104eda88f33fd578c71

ESP-32 Arduino setup: https://www.hackster.io/abdularbi17/how-to-install-esp32-board-in-arduino-ide-1cd571
4

Place the ESP-32 + reed switch on the top of the freezer
5

Stick the magnet to the freezer door, a few inches away from the reed switch
6

Connect the battery to the ESP-32
7

Calibrate

Hit the reset button on the ESP-32. If the built in LED flashes, slide the magnet a little closer. Repeat. Once the light does not flash, your system is ready to go.

Quick n' Dirty Freezer Door Alarm