It will find and hold the fan at the necessary power level (like 22% power) to keep a cupboard cool and adjust as necessary. The process led me to this smart thermostat which intelligently controls the speed of the 12v-fan to maintain a perfect temperature in your cabinet. Very wife-unfriendly and annoying when you're watching a movie to hear the fan buzzing every other minute. That didn't work for me because the fans were loud and toggling on/off. I previously had a thermostat which simply toggled the fan when the temperature crossed a threshold. My wife likes to keep the door neat and closed, so it needs some cooling! Also in that Media Console is a Macmini, a Raspberry Pi and a few other devices.

My sons's Playstation 5 sits in our TV Console which runs hotter than Sol. The electronic parts are $29 USD including the ESP32.

The hardware is an ESP32 with a regular 12v 120mm Computer Fan (PWM) and a Temperature Sensor (DHT11). The software is ESPHome and Home Assistant.

This project describes how to build a quiet thermostat controlled fan for cooling your media console, gaming cupboard or anything else.

Pwm fan control