This project was actually finalized over 2 years ago, but I want to document it for completeness sake now after the fact. It is my first from scratch project that was actually deployed

Background

I have a NAS and server box running since a few years. The two boxes together dissipate approximately 120W all day. This might not sound much, but crammed into the space under the stairs it will heat it up substantially. On a hot summer day, the temperature can easily reach 35C, which is a bit to hot for my liking. The boxes will need to stay there, so the space must be cooled.

The idea

The idea is pretty simple. There is a gap under the first step that can be used to draw in cool air. I plan to fill this gap with a wooden "plug" with 12V PWM computer case fans installed to it. The fans are speed controlled by a controller card of my design, that will use a STM32 board as the brains. I also want to have it connect to my Homeassistant instance to exchange data. Data that will be sent to homeassistant should be status and speed of all the fans. In the other direction, there should be communication for temperature target and manual controls of speed should that be necessary.

Goals and objectives

My goals for this project are pretty simple

• Learn to write C code
• Learn to use the STM32 series of microcontrollers
• Design and assemble a PCB