PM values are often close to 0 (<1)
1.The air is clean. PM are expected to be set to 0 (<1) or to show blue on the device if the air is clean.
- The sensor module filter is clogged with dust. This may happen if the device has been running for a long time in a polluted environment.
- Confirm that the sensor is functioning by turning off the air purifier, or by applying dust to the sensor (for example: by shaking dusty cloth next to sensor). You should see a peak in PM values after this action.
- Try vacuuming the sensor module filter and test again
If above actions do not change the status, contact the Blueair Customer Support.