Use of VOC sensors for air quality control of building ventilation systems

Abstract. Air quality control with VOC (volatile organic compound) sensors in residential buildings could increase user comfort by adapting to the actual contaminant level. Preliminary tests assessed the dynamics of VOC levels in single-family passive houses with a ventilation system. At normal and exceptional usages, sufficient signal variations were measured for air quality control. An air quality control was developed and tested in four single-family passive house dwellings to control the building ventilation system via VOC sensors and a special adaptation algorithm to handle variable contaminant loads and sensor drift. Results showed good operation of the air quality control for the ventilation system, detecting changing contaminants within a few minutes and changing the air flow rate in the building immediately. The 43 VOC sensors used during the monitoring had more than 1.2 million working hours in total without any electrical failure, but with a loss of sensitivity for the calibration gas CO. The air quality control could manage that loss of sensitivity and worked well till the end of the field test. A comparison between VOC and CO₂ sensors in one building resulted in more detailed information about emission rates in the room with the VOC sensor, allowing one to get a better reaction of the ventilation system.