This isn’t about connecting a temperature sensor in your Arduino. This build is about using the temperature sensor in your clock.

[Flux Axiom] is using an Arduino Mega in his setup along with a cornucopia of sensors and all their data is being logged onto an SD card.

I used an LCD shield to display the current temperature and speed of the fan, but you can use the circuit without the LCD display. You also need to select the transistor by the type of fan that you ...

You'll need an Arduino along with a bunch of various sensors to get the project rolling, and once it's all set up you'll have a simple, but cheap system to monitor your home.