Performance assessment of a humidity-controlled ventilation system.

Demand controlled ventilation systems have recently become an interesting opportunity to achieve acceptable indoor air quality while minimizing energy consumption. Although they are usually designed for buildings showing relevant variations of occupancy (e g, office buildings, schools, etc.), there are now examples of applications also in residential buildings. One example is the passive humidity-controlled ventilation system recently developed in France. This type of installation has been tested in a five- storey apartment building located in Torino, Italy, during the winter 1989. Preliminary results, concerning air temperature and relative humidity data and system operation, are presented in this paper. Analysis of data shows that the system is capable of maintaining air humidity levels below the limit values in most situations, reacting effectively to changes in the occupancy patterns and activities. The energy savings compared to a conventional constant flow ventilation system have also been calculated.