Calibrating Your Airmonitor Plus

To ensure accurate readings, Airmonitor Plus requires manual calibration before first use.

Only the CO₂ sensor supports manual calibration. The remaining sensors automatically compensate during normal operation and do not require user calibration.

When should I calibrate the CO₂ sensor?

After the initial set-up, we recommend calibrating the CO₂ sensor only if:

• CO₂ readings appear consistently inaccurate.
• The monitor has been transported over a long distance.
• The device has been stored for an extended period.
• You simply want to verify the sensor's accuracy.

For most users, calibration is only required occasionally.

How to Calibrate the CO₂ Sensor

1. Place the monitor in fresh outdoor air.
2. Wait at least 5 minutes for the reading to stabilize.
3. Press the rear multifunction button three times quickly.
4. The CO2 display will indicate that calibration has started by changing to "--"

Once complete, the CO₂ reading should settle at approximately 400–420 ppm, which is the normal concentration of outdoor air.

Important Notes

• Perform calibration in clean outdoor air.
• Do not calibrate indoors, as indoor CO₂ levels are typically much higher than fresh outdoor air.
• Avoid calibrating near traffic, barbecues, generators, or other sources of combustion.
• During calibration, avoid breathing directly towards the monitor.

If your CO₂ reading remains significantly different from expected values after completing the calibration procedure, please contact Breathe Tech Support and include a photo of the display along with a brief description of the issue.