Abstract: An air diffuser of a heating, ventilation, and/or air conditioning (HVAC) system includes a mixing chamber having a circulation inlet and a mixing region, a room air intake fluidly coupled with the circulation inlet and separated from the mixing region by a blank-off plate, and a nozzle. The nozzle is disposed adjacent to the circulation inlet and configured to accelerate a conditioned air flow into the mixing region such that unconditioned room air is induced by the conditioned air flow to enter the mixing region through the circulation inlet and from the room air intake.

Abstract: A system comprising a furnace, an impeller, and a controller. The impeller directs air into an environment through the furnace. The controller receives calls to heat the environment or circulate air in the environment. In response to receiving a call to heat the environment, the controller activates the furnace and the impeller such that the impeller draws a first amount of power and turns in a first direction causing air to be impelled from the impeller through the furnace into the environment. In response to receiving a call to circulate air in the environment, the controller activates the impeller such that the impeller draws a second amount of power and turns in a second direction causing air to be impelled from the impeller into the environment, wherein the second amount of power is less than the first amount of power and the second direction is opposite the first direction.

Abstract: A mixer for mixing air flows is provided that can include an air duct, which has at least one hot air duct and one cold air duct, wherein an air flow through the hot air duct and through the cold air duct can be controlled by a respective mixing flap. A heating element is arranged in the hot air duct in order to heat the air passing through the hot air duct. Furthermore, the mixer can include a mixing chamber, which is connected to an air outlet side of the hot air duct and of the cold air duct of the air duct such as to enable fluid flow. The mixing chamber can have air guiding elements, which are arranged in such a way that air flowing out of an air outlet side of the hot air duct crosses air flowing out of an air outlet side of the cold air duct.

Abstract: The present teachings provide for an HVAC assembly. A first flue can be configured to fluidly couple a first heat exchanger to a mixing flue. A second flue can be configured to fluidly couple a second heat exchanger to the mixing flue. A door can inhibit fluid communication through the second flue when in a first position. The door can inhibit fluid communication through the first flue when in a second position. The door can permit fluid communication through the first and second flues when in a third position. The third flue can be configured to fluidly couple the first heat exchanger to a portion of the second flue downstream of the second heat exchanger and upstream of the mixing flue when the door is in the third position.

Abstract: A foldably tensioned boot loadable air damper device for controlling the flow of air through ductwork, and a method of installing same. The damper device includes an actuator having a retractable member and a pivoting member, wherein the pivoting member is operatively connected to the retractable member of the actuator. The damper device also includes at least one support base supporting the actuator and the pivoting member with respect to each other, a foldable damper blade attached to the pivoting member, and at least one tensioned hinge member operatively connected to the foldable damper blade for unfolding the damper blade. The damper device may be inserted through a register boot and into a ductwork when folded.

Abstract: An air duct includes a main body, and an adjusting assembly. The main body includes a top plate and two lateral plates extending from opposite sides of the top plate. The adjusting assembly includes two first limiting plates, a second limiting plate, and a third plate. The second and third limiting plates are slidably attached to each other, and are respectively pivotably attached to the first limiting plates. Each first limiting plate is adjustably attached to the lateral plates.

Abstract: A shutter system includes a first louver element having a first pivot axis and a second louver element having a second pivot axis. The first louver element is configured to rotate about the first pivot axis, and the second louver element is configured to rotate about the second pivot axis. The shutter system additionally having a flexible drive element connecting the first louver element and the second louver element to thereby substantially synchronize the rotation of the first and second louver elements.

Abstract: A device for controlling an airflow in a ventilation duct, comprising a pivotable air flap, which prevents an airflow in the duct when in the closed position. A housing of an actuator for the air flap, which may pivot freely about the relevant longitudinal mid plane, is mounted in the inner duct wall. The air flap, symmetrically or approximately symmetrically curved about the longitudinal mid plane of the ventilation duct and supported under load in a stable position on the duct wall, is rigidly fixed to the driveshaft of the actuator, by an angled lever arm, with a separation, in the region of the apex line thereof. The air flap rests roughly centrally, permanently on the points of contact with the inner duct wall, which move with the position of the flap, in a self-centering manner and, in the closed position, contacts the inner duct wall along a sealed, endless peripheral sealing surface.

Abstract: An air duct includes a top plate, two side plates extending from two lateral sides of the top plate, a baffle plate extending from the top plate and located between the side plates, and a torsion spring connected between the top plate and the baffle plate. The top plate and the side plates cooperatively define an air passage in the air duct. The baffle plate includes a first end pivotally connected with the top plate and an opposite second end. The second end of the baffle plate is rotatable relative to the top plate. The torsion spring includes two arms abutting against the top plate and the baffle plate, respectively. When the baffle plate is rotated relative to the top plate under an external force, the torsion spring resists such force.

Abstract: The invention relates to a device (12), for controlling an airflow (A) in a ventilation duct (10), comprising a least one pivotable air flap (24), which prevents an airflow (A) in the duct (10) when in the closed position. A housing (32) of an actuator for the air flap (24), which may pivot freely about the relevant longitudinal mid plane (LM), is mounted in the inner duct wall (34) of constant cross-section. The elastic air flap (24), symmetrically or approximately symmetrically curved about the longitudinal mid plane (LM) of the ventilation duct (10) and supported under load in a stable position on the duct wall (34), is rigidly fixed to the driveshaft (18) of the actuator, by an angled lever arm (20), with a separation (a), in the region of the apex line (S) thereof.

Abstract: An improved air volume regulator used in HVAC operating at a static pressure below 25 pa. (0.1?w.g.) having a pair of opposing gates facing into the airflow and a V shaped baffle positioned to form two constricting passageways. Air flowing through the passageway generates a light vacuum at its throat and combined with the static pressure differential across the gates urges them towards the baffle and constricts the airflow. A counterbalance spring cooperating with a concave cam and cam follower applies a resisting bias on gates such that the airflow in the regulator remains constant under varying inlet conditions. A variable spring rate mechanism permits the adjustment of the airflow rate over the full operating range using a single counterbalance spring. A cable driven “limited torque” flywheel controls the air volume regulator's propensity to pulsate under unstable inlet airflow conditions.

Abstract: The invention concerns a supply air terminal device (10) including a supply chamber (11) for the supply air and in the supply chamber (11) nozzles (12a1, 12a2 . . . ; 12b1, 12b2 . . . ), through which the supply airflow (L1) is conducted into a side chamber (B1) of the supply air terminal device, which side chamber is a structure open at the top part and at the bottom part. The supply air terminal device (10) includes a heat exchanger (14), which can be used either to cool or to heat the circulated airflow (L2). In the device solution, fresh supply air, which is conducted through the nozzles to the side chamber (B1), induces the circulated airflow (L2) to flow through the heat exchanger (14). The combined airflow (L1+L2) of supply airflow (L1) and circulated airflow (L2) is conducted out of the supply air terminal device (10). The supply air terminal device includes an induction ratio control device (15), which is used to control how much circulated airflow (L2) joins the supply airflow (L1).

Abstract: A dual-channel mixing box (1) is arranged in series with other such mixing boxes in order to regulate the temperature of the air in one room each or in several rooms. Each mixing box is provided with supply pipes (3,4) running through it, in which air of different temperatures flows. Each supply pipe is provided with a damper (5), the dampers in a mixing box (1) being adjustable by means of a motor-operated rod (6) so that when one damper is moved in closing direction, the other damper is moved in opening direction, and vice versa. A mixing chamber (11) for the air from both supply pipes is formed between the supply pipes (3,4). The mixing chamber is in controllable communication with one or two outlet chambers (12) communicating through pipes with the room(s) in which the temperature is to be regulated via the mixing box in order to supply a mixture of air with the desired temperature.

Abstract: A circulation air distributing system for supplying fresh conditioned, hot or cold air through the use of cells metal cellular flooring. Distribution box inserts are uniformly distributed along the cellular flooring units prior to concrete placement. Selected distribution box inserts are activated to provide individual control means including diffuser means, for supplying individual workstations with fresh air at the volume, the temperature, and in the direction desired by the occupant. Air movement is from the floor surface upwardly toward the ceiling and into a return plenum space provided above the ceiling structure. In the event of a fire, selected diffuser means may be replaced by mask assembly which provide fresh, breathable air to an individual. Signal means activated on connection of the mask assembly to the control means, alerts the fireman as to the location where rescue is required.

Abstract: A method and apparatus for emulating a perimeter induction unit, in which the perimeter induction unit is replaced by an emulation unit carried in a plenum above the space to be heated or cooled. A temperature sensor is mounted within the space, and a computer provides programmed control, either centrally or locally. The emulation unit is connected to the primary air ducts and secondary liquid source formerly used for the perimeter induction unit. It includes a primary air inlet for accepting and regulating a flow of ventilated, preconditioned primary air from the primary air ducts, and a secondary air inlet for accepting a flow of return air from the space as well as filtering the return air and passing it over a heat exchanger carrying secondary cooling liquid at a preselected temperature. Primary and secondary air is mixed within a mixing chamber and delivered to the space by a blower at a preselected combined air volumetric flow rate.

Abstract: A series-type fan includes an air intake exposed to both ambient and forced ventilation air, a variable capacity fan, and multiple ports positioned downstream from the fan. One of the ports has a damper attached thereto which closes when the fan is de-energized to prevent backspin of the fan.