Introduction: Add a Temperature Switch to Your Dusty Old Fan!

About: Hi there visitor! First of all thank you for checking out my profile! My name is Youri. I study Technical Computer Science in the Netherlands. I especially love the electronical part of my study. Since I lov…

So, I had a old fan lying around and I thought, why not automate it? :D
I used a Arduino as a temperature switch, so I don't have to worry about "overheating" my brain anymore.

Components needed:

  • Breadboard
  • Arduino
  • 10K potentiometer
  • BD137
  • LCD Display
  • Temperature (and humidity) sensor
  • 220 Ohm resistor
  • Breadboard cables
  • (5 Volt) fan

Step 1: Watch the Video!

Also don't forget to like and subscribe for more ;)

Step 2: Connecting the LCD Display

First off, we start by connecting the LCD Display to the Breadboard. After that we follow the schematic to connect the cables to the Arduino.

You will need both the resistor and the potentiometer for this step.

If you don't understand the wiring then feel free to ask!

Step 3: Connecting the Sensor

Once the LCD is wired up it's time to add the sensor.

The sensor will go onto pin 11 of your Arduino.

Step 4: Testing the LCD and Sensor

Upload the code given in this step and check whether your sensor and LCD are working.

You can test the sensor by heating it with your breath or fingers. You should see the temperature go up.

Step 5: Connecting the Fan to Your Breadboard

Since the fan uses 5 Volt we can use a USB cable to power the fan. We can't use the 5 Volt output of our Arduino since the fan needs a lot more current than the Arduino can deliver, so this means you will probably end up frying your Arduino if you attempt this.

We (ab)use a transistor (BD137) in order to switch the power that goes to the fan.
You can take a look at the schematic if you don't know how to connect the USB cable to the transistor and fan.

Step 6: Testing the Circuit

Once everything is wired up and you have uploaded the code you can connect the USB cable of your fan to a USB port to power the fan and once the temperature goes above 25*C the fan will be powered which means our fan starts spinning.

If everything works our project is DONE!