Patent ID: 8974275
Filing Date: 2015-03-10
Classification: F24F

Abstract:
1. A passive ventilation stack for a room or building, the stack having an interior space, a first opening which in use is configured for two way fluid communication through a first aperture defined by the first opening between the interior space and the room or building to be ventilated, and a second opening which in use is configured for two way fluid communication through a second aperture defined by the second opening between the interior space and ambient atmosphere, the interior space in use being configured for mixing air entering the stack from the room or building and air entering the stack from the ambient atmosphere, and a control system for varying the size of at least the second opening, wherein the first opening is configured to provide mixing of air flow through the first aperture defined by said first opening from both the room or building and from the interior space, and wherein the interior space for mixing air is disposed between the first opening and the second opening, and wherein the control system is configured to vary a size of both the first opening and the second opening.