Q: My Zen LED's have gone dark. Did they fail?

Double tap the top of the sensor. An example video is found here. If it doesn’t change brightness, try tapping harder as gentle taps may not register.

Also keep in mind that only PurpleAir Touch and Zen sensors can be tapped to change brightness. Older PA-I-Indoor devices do not have this feature.

If your sensor still doesn’t change brightness, send an email with the device ID to contact@purpleair.com.