Abstract: A two stage air purification system is provided for the removal of airborne impurities from an airflow prior to the airflow entering a building's ductwork. In particular, a primary air filter is mounted within the hood of, for example, a cooking area and operable to receive grease-laden air and remove a portion of the impurities. The air is then sent to a secondary filter, also mounted within the hood, that removes additional impurities. The air is then sent through the building's ductwork and eventually out the building.

Abstract: A two stage air purification system is provided for the removal of airborne impurities from an airflow prior to the airflow entering a building's ductwork. In particular, a primary air filter is mounted within the hood of, for example, a cooking area and operable to receive grease-laden air and remove a portion of the impurities. The air is then sent to a secondary filter, also mounted within the hood, that removes additional impurities. The air is then sent through the building's ductwork and eventually out the building.

Abstract: A two stage air purification system is provided for the removal of airborne impurities from an airflow prior to the airflow entering a building's ductwork. In particular, a primary air filter is mounted within the hood of, for example, a cooking area and operable to receive grease-laden air and remove a portion of the impurities. The air is then sent to a secondary filter, also mounted within the hood, that removes additional impurities. The air is then sent through the building's ductwork and eventually out the building.

Abstract: The present invention provides a centrifugal air filter suitable for extracting impurities suspended in air. The filter includes a front wall, a rear wall spaced from the front wall, and a perimeter wall joining the front and rear walls and forming a cavity therebetween. Dividers divide the cavity into a plurality of vortex chambers. Each vortex chamber has a pair of inlets proximal opposing chamber ends and formed in the filter front wall, and an outlet formed in the filter rear wall generally centrally disposed between the inlets. Each vortex chamber extracts impurities by directing the air along a helical path through the vortex chamber from the inlets to the outlet. Air enters the vortex chamber inlets in the front of the filter, and exits the vortex outlet at the rear of the filter in the same plane.

Abstract: An upblast exhaust fan for commercial kitchens is constructed with components that are coated with a dry lubricant. The non-stick surfaces that collect grease condensed from the hot cooking gases are easily cleaned with hot water during routine maintenance.

Abstract: An upblast exhaust fan for commercial kitchens is constructed with components that are coated with a dry lubricant. The non-stick surfaces that collect grease condensed from the hot cooking gases are easily cleaned with hot water during routine maintenance.

Abstract: A ventilation system for a single or stacked conveyor ovens includes an exhaust canopy which extends across the top of the ovens and defines exhaust channels positioned above the conveyor openings on opposite sides of the ovens. A make-up air system delivers make-up air beneath each conveyor opening where it is directed upward through an air curtain nozzle to produce an air stream that directs cooking gases emanating from the conveyor openings upward and into the exhaust channels.

Abstract: A ventilation system for institutional and commercial cooking equipment includes a hood which is placed over the equipment and which attaches to an exhaust duct and fan that removes a relatively constant volume of air from beneath the hood. A make-up air supply divides to form a fresh air duct that connects to the hood and a tempered air duct which also connects to the hood. The fresh air is directed beneath the hood by fresh air registers and the tempered air is directed into the surrounding room by tempered air registers. The relative amounts of fresh air and tempered air can be changed by a damper, but the damper does not significantly alter the total amount of supplied make-up air. The system can thus be adjusted to use more or less tempered air as various combinations of cooking equipment are used without affecting the overall balance of exhaust air and make-up air.