Red Balloon Carbon Monoxide Detector

The carbon monoxide sensor detects high levels of CO-gas concentrations in the air. When the concentration reaches a high level (which we pre-set) the LED changes color from green to red.

Step 1: Components

Main Components

Arduino Uno

Carbon Monoxide Sensor - MQ-7

RGB Led Common Anode

USB Cable A to B

Battery Holder - 4xAA

Secondary Components

100 Ohm Resistor

220 Ohm Resistor

Gas Sensor Breakout Board

10K Ohm Resistor

BreadBoard - Half Size

Jumper Wires Pack - M/M

Male Headers Pack- Break-Away

Step 2: Assembling the Circuit

Click here for a detailed wiring guide and test code. Don’t forget to solder the MQ7 sensor to its breakout board.

After you wire the circuit, you’ll also need to:
1. Solder a wire ribbon to the Q7 sensor. We used a 15 feet ribbon (approx. 5 meters). 2. Optional: Use crimps at the tips of the ribbon to connect it to the breadboard.

Step 3: Code for the Project

1. Use the test code you received in the original reply, to verify that the wiring is correct. Open the serial monitor and follow the instructions.

2. Download the code for the CO detector and extract it to your computer from our Github Repo.

3. Open it with the Arduino IDE

4. Set the correct port and board

5. Set the pins according to your wiring

6. Upload the code to the Arduino.

For more information about the code logic and the project visit our blog.

Step 4: Buy a Balloon and You’re Ready to Go!

Now that the circuit and code are ready, all that's left to do is get a balloon and connect the MQ7 co detector to it using zip-ties.

Step 5: Have Any Questions? Want to Start Your Own Project?

We are more than happy to answer your questions and get feedback on our forum - talk.circuito.io or in the comments below.

Enjoy Making!