Control of ventilation rate in buildings using H20 or CO2 content.

Examines CO2-controlled ventilation for a variety of buildings. A theoretical study shows that the modification of the ventilation rate which can be obtained by the control of a 2 speed fan or by variation chimney cross-section enables the ventilation rate to be independent of external conditions (wind, temperature) and to produce annual energy savings of the order of 1500-2000 KWhr for a 100m2 house. Conducts an experimental study to measure the change in CO2 and H2O content in a dwelling and to examine the possibility of using one of these two parameters to control a mechanical or natural ventilation system. Concludes that the CO2 content is a suitable parameter for ventilation control, and that experimental results agree with theoretical calculations.