Patent ID: 7752858

Claim:
A system for exhausting air from an equipment enclosure, the system comprising: an exhaust unit including a housing configured to connect to the equipment enclosure, the housing defining a front panel, a back panel opposite to the front panel, a top portion and a bottom portion opposite to the top portion; the front and the back panels and the top and the bottom portions defining an interior chamber within the housing, and enclosing at least one inner duct defined within the interior chamber, the at least one inner duct being disposed and configured to direct air to the top portion of the housing; the back panel being a solid panel and being configured to connect in facing relation to the equipment enclosure, the back panel defining at least one port; an outer exhaust duct that has a first end and a second end, the first end being constructed and arranged to couple to the at least one inner duct along the top portion of the housing; and at least one fan configured to sit in the at least one port in facing relation to the equipment enclosure, and being disposed and configured to place the interior of the at least one inner duct in fluid communication with the interior of the equipment enclosure and to draw air from within the interior of the equipment enclosure and to vent drawn-in air into the interior of the at least one inner duct and out through the outer exhaust duct, wherein the at least one fan is configured to operate at a variable speed or at a constant speed; a controller coupled to the at least one fan and constructed and arranged to control the speed of the fan, wherein the controller is constructed and arranged to sense opening of the equipment enclosure or the exhaust unit and to control the at least two fans to operate at maximum speed when the equipment enclosure or the exhaust unit is opened.