Abstract: A flow control device has a duct section with a plurality of damper blocking elements, each having a major plane. The damper blocking elements are pivotably connected to the duct section and movable in a range that is limited to ensure that, when the duct section is mounted in a preferred orientation, the damper blocking element major planes always form an angle of at least 45 degrees from the horizontal throughout the range. The range is such that the plurality of damper blocking elements can selectively close and open the duct. The blocking elements can completely close the duct, for example, to block natural convection.

Abstract: An autonomous ventilation system includes a variable-speed exhaust fan, a controller, an exhaust hood, and an infrared radiation (“IR”) sensor. The exhaust fan removes air contaminants from an area. The controller is coupled to the exhaust fan and adjusts the speed of the exhaust fan. The exhaust hood is coupled to the exhaust fan and directs air contaminants to the exhaust fan. The IR sensor is coupled to the controller, detects changes in IR index in a zone below the exhaust hood, and communicates information relating to detected changes in IR index to the controller. The controller adjusts the speed of the exhaust fan in response to information relating to detected changes in IR index. The autonomous ventilation system also includes an alignment laser to indicate a point at which the IR sensor is aimed and a field-of-view (“FOV”) indicator to illuminate the zone in which the IR sensor detects changes in IR index.

Abstract: An exhaust hood includes a top wall extending in a horizontal direction, a convexly curved front wall extending in a vertical direction from the top wall. The hood also includes a filter support plate that holds a grease filter under the top wall and horizontally spaced from the front wall. The support plate is angled such that a bottom edge of the plate is farther in the horizontal direction from the front wall than a top edge of the plate proximal to the top wall. Surfaces of the top wall, the front wall, the filter support panel, and of a baffle under the support plate bound a chamber through which fumes flow to the grease filter. A free end of the front wall can be closer to the top wall than a portion of the front wall between the first end and the free end of the front wall.

Abstract: Systems, devices, and methods for determining whether a fire condition exists based on a status of a cooking appliance, and systems, devices, and methods for controlling an exhaust air flow rate in an exhaust air ventilation system based on the status of the cooking appliance. At least one sensor type generating a predefined signal is used to detect fire condition and appliance cooking state, the predefined signal being applied to a controller which differentiates, responsively the predefined signal, in combination with other sensor signals, at least two cooking states each of the cooking states corresponding to at least two exhaust flow rates which the controller implements in response to the controller's differentiation of the two states and which predefined signal is simultaneously used to differentiate a fire condition, in response to the differentiation of which, the same controller activates a fire suppression mechanism.

Abstract: An exhaust system includes a ventilated ceiling component with multiple surfaces and recesses. Each recess has an exhaust intake, the recesses being distributed over an area of a ceiling that has a perimeter adjacent the recesses. The perimeter has a jet register located below the exhaust intake and configured to generate jets, a first of the jets being directed toward and located below at least one of the exhaust intakes and a second of the jets being directed substantially vertically downward. The perimeter further has a displacement ventilation register.

Abstract: In embodiments, a control system for a UV air treatment system, especially one used for cleaning a fume stream such as in a kitchen exhaust system, detects a need for cleaning maintenance on the UV light source based on changes in light intensity. The system further detects the light intensity each time the UV light source is cleaned to determine if the drop in intensity after cleaning indicates that the UV light source should be replaced. The cleaning and replacement requirements are indicated automatically by a user interface.

Abstract: An autonomous ventilation system includes a variable-speed exhaust fan, a controller, an exhaust hood, and an infrared radiation (“IR”) sensor. The exhaust fan removes air contaminants from an area. The controller is coupled to the exhaust fan and adjusts the speed of the exhaust fan. The exhaust hood is coupled to the exhaust fan and directs air contaminants to the exhaust fan. The IR sensor is coupled to the controller, detects changes in IR index in a zone below the exhaust hood, and communicates information relating to detected changes in IR index to the controller. The controller adjusts the speed of the exhaust fan in response to information relating to detected changes in IR index. The autonomous ventilation system also includes an alignment laser to indicate a point at which the IR sensor is aimed and a field-of-view (“FOV”) indicator to illuminate the zone in which the IR sensor detects changes in IR index.

Abstract: An exhaust device for convection or combi ovens captures exhaust from opening side-opening oven doors with minimal energy waste.

Abstract: A ventilation exhaust intake device is located at ceiling level of a production space and has a low profile form with combination of vertical and horizontal jets. Recesses and other feature are provided to enhance capture and containment and other functional aspects. Certain embodiments include a light source adjacent the jet registers.

Abstract: A system and method for controlling the exhaust flow rate in an exhaust ventilation system including an exhaust hood positioned above a cooking appliance. The method can include measuring a temperature of the exhaust air in the vicinity of the cooking appliance, and measuring a radiant temperature of a surface of the cooking appliance, and determining an appliance status based on the measured exhaust air temperature and radiant temperature, and controlling the exhaust flow rate in response to the determined appliance status.

Abstract: A system and method for controlling the exhaust flow rate in an exhaust ventilation system including an exhaust hood positioned above a cooking appliance. The method can include measuring a temperature of the exhaust air in the vicinity of the cooking appliance, and measuring a radiant temperature of a surface of the cooking appliance, and determining an appliance status based on the measured exhaust air temperature and radiant temperature, and controlling the exhaust flow rate in response to the determined appliance status.

Abstract: A device and method for air purification used in cooling, heating and air ventilation systems. The device has at least one UV light source positioned on an inside portion of a movable access panel so that it moves with the access panel from a first position where the UV source directs UV light towards the inside of the system to purify the air stream inside and to remove contaminants from the surfaces inside the system, to a second position where the UV source directs UV light towards the space surrounding the system so that it purifies the air in the room where the system is mounted.

Abstract: A flow control system for controlling exhaust flow can measure effluent escaping from the exhaust hood at a given flow rate. An interferometric detector can measure fluctuations in fluid properties external to and/or in the vicinity of the exhaust hood. The flow control system may vary a flow rate of the exhaust hood and/or control exhaust hood structures responsive to the measurements to contain the effluent while minimizing the exhaust of air from the occupied space.

Abstract: A device and method for air purification used in cooling, heating and air ventilation systems. The device has at least one UV light source positioned on an inside portion of a movable access panel so that it moves with the access panel from a first position where the UV source directs UV light towards the inside of the system to purify the air stream inside and to remove contaminants from the surfaces inside the system, to a second position where the UV source directs UV light towards the space surrounding the system so that it purifies the air in the room where the system is mounted.

Abstract: A flow control system for controlling exhaust flow can measure effluent escaping from the exhaust hood at a given flow rate. An interferometric detector can measure fluctuations in fluid properties external to and/or in the vicinity of the exhaust hood. The flow control system may vary a flow rate of the exhaust hood and/or control exhaust hood structures responsive to the measurements to contain the effluent while minimizing the exhaust of air from the occupied space.

Abstract: A low profile exhaust hood has a high inlet and a high aspect ratio of horizontal to vertical. A sloping wall of the recess guides hot plumes upwardly to the inlet. The inlet is sized to provide an exhaust face velocity that is at least as high as a highest possible plume velocity for a 400 F oven. The inlet is located high and forwardly to cause a suction zone to be generated near the forward edge of the hood to aid in capturing plumes tending to escape which are remote from the sloping wall.

Abstract: Energy recovery devices, systems and methods, and energy recovery control systems and methods for efficient extraction and reuse of waste heat from exhaust fumes generated from cooking appliances.