Installed in a wall housing, the unit measures the air quality (VOC fumes), humidity and temperature. The measured value is displayed by three coloured LEDs, which indicate the following VOC content:

• Green: < 800 ppm (good air quality)
• Yellow: 800…1200 ppm (okay air quality)
• Red: > 1200 ppm (bad air quality).

The probe is available in a simple version which just measures VOC and in a version with a rely which measures VOC, temperature and humidity. A fan or window regulators can be controlled with the relay.