The CO2 sensor can be calibrated using the calibration button on the sensor box. This button sets the reading of the sensor to a value around 400 ppm CO2 (the theoretical CO2 concentration value in fresh air).
- Place the 250 mL sampling bottle delivered with your sensor in the air outside long enough to ensure that its content is replaced with fresh air.
- While still outdoors, insert the sensor with the rubber stopper into the bottle. You can now take the bottle and the sensor to the location where the measurements will be performed.
- Connect the CO2 sensor to an interface and let the sensor warm up by collecting data for at least 5 minutes.
- When the readings stabilize use a paper clip or a ballpoint to press down the calibration button. After about 30 seconds, the reading should stabilize at a value around 400 ppm.