Fc-22 Gas sensor Arduino

Introduction

MQ-2

Theory

Connect Vcc, GND and Analog Output to Arduino Analog A0 pin (see https://www.instructables.com/How-to-use-MQ2-Gas-Sensor-Arduino-Tutorial/). Also, there is Digital Output.

#include "MQ135.h"

MQ135 gasSensor = MQ135(A5);

int ppm = gasSensor.getPPM();

void setup() {
  Serial.begin(9600);
}

void loop() {
  float rzero = gasSensor.getRZero(); #Calibaration. Actually it takes ~24h time.
  float ppm = gasSensor.getPPM();
  Serial.println(ppm);

  delay(1000);
}

See https://github.com/Ravenneo/CO2-sensor

Calibration https://hackaday.io/project/3475-sniffing-trinket/log/12363-mq135-arduino-library