Connecting an Air Quality Sensor directly to an arduino


I am new at this so this might be an obvious question.

I have an AirQuality Sensor that I would like to connect to an Arduino Uno. Unfortunately I dont have the brick , I need to connect the 4 cables coming out of the sensor directly to the Arduino board.

Does anybody have any suggestions how to connect the cables? I presume that the red should go to the 5v pin and the black should go to gnd, but what about the yellow and the white? What pins should they go into?

Also, any suggestions as to how to access in an Arduino sketch the values for CO2, CO Methane and Alcohol?


I do not have this product but briefly looking over its wiki page tells me it is an analog sensor.

The PCB silkscreen has appropriate signal labels for the pins.
It looks as if (assuming you are using the same cable shown on the wiki page):
Red is Ground
White is Vcc
Yellow is Not Connected
Black is Analog Voltage Output

There is an example sketch on the wiki page using A0 as the input for the sensor.

You will only get an indication of fresh air or polluted air. It will not indicate levels of any specific gases, just a level of air quality.

Hope this helps…

Wiki Page: … ity_Sensor

Thanks so much for your answer. I got the air working ok. I am trying to do the same with the Temperature and Humidity Pro just connecting the white to an analog input and red and black to red and black but I am not getting any signals, Do I need a yellow for the the Temp&Hum Sensor Pro?


I have the Pro and therefore I am assuming that I need to use #define DHTTYPE DHT22, but I have tried the three values and none of them work. I am connecting the white pin to digital 10, is that a problem?


The pin which should be connected to Arduino depends on the code:

#define DHTPIN 2     // what pin we're connected to

So if it is defined in the code, you should connect the sensor to digital 2 of Arduino.