Type REDC Recirculating (exhaust/recirculation) Roof Ventilator

APPLICATIONS: Type REDC recirculators are multi-purpose power roof ventilators, used for exhaust or recirculation. They are suggested for use in commercial and industrial applications where there is sufficient ceiling height to create a temperature differential between the floor and ceiling. These applications include factories, warehouses, and large commercial buildings. Type REBC recirculators function as normal power roof ventilators in warmer weather and as an energy-saving recirculation system in cold weather. Each unit is equipped with a reversible fan that redistributes warm ceiling air throughout the plant and reduces the building’s heating requirement. With the flip of a switch, it can function as a conventional roof ventilator.

CONSTRUCTION: Type REDC PRVs can exhaust to the outside, or recirculate inside building air. With the addition of an optional modulating damper motor, various amounts of outside air may be mixed with recirculated inside building air. The fan/damper plenum is suspended from a roof opening, and a hood and base are mounted to a curb above the opening on the roof. The hood and base are made of galvanized steel. An exterior finish coat of epoxy can be specified. Motor operated, center pivoted dampers are located in the sides of the plenum and at the top of the plenum in the throat of the roof curb. Dampers are linked together so that as the throat damper closes, the plenum dampers open and vice versa. All dampers are shipped installed in the plenum. When the direction of airflow is up, the dampers in the sides of the plenum are closed and the damper at the top of the plenum is opened creating an exhaust PRV. When the direction of airflow is reversed and the damper arrangement is not changed, the unit acts as a supply PRV. With the direction of airflow down and the damper positions reversed, a recirculating unit is created. For directing airflow from the plenum into the plant area aThree-Way Diffuser is used. It is shipped mounted to the plenum. The 14 gauge frame and 20 gauge blades are constructed of galvanized steel. MODULATING DAMPER MOTOR is desirable to maintain a predetermined inside temperature by mixing varying amounts of recirculated plant air and cool outside air. The modulating motor, complete with linkage, electronic temperature controller and transformer are mounted within the plenum. A remote temperature sensor with set point is also provided for mounting and wiring in teh field.

Deep mines, underwater tunnels, and other subterranean and submarine environments require elaborate mechanically operated systems for maintaining the air supply in a healthful condition. The lives of those working in, or traveling through, such areas depend upon a constant supply of fresh air; not only must the systems used be highly efficient, but there should be provision for emergencies in case of failure of the apparatus in operation. An outgrowth of studies of problems of ventilation is the development of methods of air conditioning heat pump is a reversible device that does mechanical work to extract heat from a cooler place and deliver heat to a warmer place. The heat delivered to the warmer place is, approximately, the sum of the original heat and the work done. Such systems, unlike ordinary methods of ventilation, are independent of outdoor atmospheric conditions and can, therefore, maintain the indoor atmosphere at the most healthful temperature and humidity and can free the air of dust and other undesirable materials. They accomplish this, however, at a considerable cost in energy.