Abstract: An improved ventilating range hood that drives a variable speed fan according to the state of four distinct air quality sensors: temperature, humidity, Carbon monoxide and smoke. A micro-controller is used to integrate the four signals and determine the appropriate ventilation requirement. This value is converted into a signal to drive the fan. Visual indicators are provided to display the state of each air quality factor. An audible alarm is activated if the levels remain at hazardous levels for more than a predetermined time interval after the fan has been turned on.

Abstract: The invention is an air handling system that is shared between a laboratory and offices within the same building. The normally separate office and lab systems have been combined by way of an air return system that draws air from the offices and feeds into both the office and lab air supplies. The re-circulation of the office air draws more fresh outside air into and lessens requirements for the heating and cooling systems for the offices.

Abstract: A biological hazard mitigation apparatus permitting a material handling operation in the vicinity of a work area includes a plenum pneumatically coupled and proximate to one side of the work area, a filter sized to trap biological hazards and including an exhaust port, a blower including an inlet port and an exhaust port, and ducting pneumatically coupling the exhaust port of the filter to the inlet port of the blower, wherein the filter is disposed in the plenum, and adjacent surfaces of the filter and the plenum are substantially equal in surface area. If desired, the ducting includes first and second ducts, permitting a silencer to be disposed between the first and second ducts. Methods for operating the apparatus are also described.

Abstract: A method and apparatus for removing airborne contaminants in residential or commercial buildings injects filtered air into these enclosures. Prior to be injected in these enclosures, the air is filtered for chemical, biological or radioactive hazards. The filtering of the air ensures that the enclosure is a safe haven. The apparatus includes an enclosure, a filtration assembly for removing airborne biological, chemical or radioactive agents mounted with the enclosure. A series of expansion slots can be mounted within the enclosure to assembly a multi-stage filtering process. A blower is also included in the apparatus for overcoming the resistance of the filtration assembly and increases the air pressure inside the building to achieve protective overpressure. A control system within the apparatus monitors the pressure and adjusts the airflow in the system in order to maintain the protective overpressure.

Abstract: An environmental control unit, and air handling systems using it, that combines, as a unitary packaged unit, equipment and associated functionality for air handling and affording protection to occupants and/or equipment in an enclosure against airborne release of chemical, biological, or radiological (CBR) agents.

Abstract: Methods and apparatus for recirculating air in a controlled ventilated environment. In one example, recirculation of air from one or more rooms in a multiple room ventilated environment having a common source of supply air is controlled such that minimum ventilation and thermal load requirements for each room are satisfied independently, so as to facilitate a reduction in the amount of fresh outside air required for the environment. In another example, the controlled airflows in each room may be based additionally on respective air quality levels of the air drawn from each room. In one aspect, if contaminants are detected in one or more rooms of the ventilated environment, the amount of air recirculated from a contaminated room back to the environment may be controlled based on a detected level of the contaminant and a dilution ratio of any returned contaminated air to the total uncontaminated air supplied to the environment.

Abstract: A centralized device for the distribution and discharge of air causing the evaporation of a carrier in a number of user installations each having an intake channel and a discharge channel, comprising a single manifold for the reception, delivery and discharge of air-carrier mixture from and to the installations and a discharge fan connected to said manifold, and comprising for each installation: a device for air supply, connected to the single manifold and having a fresh air suction channel and an air supply channel, a fan connected to the air supply device, a heat exchanger connected to the fan and to the intake channel of the installation, a discharge device connected to the discharge channel of the installation and to the manifold and comprising a discharge channel, and a recirculation device comprising a recirculation channel connected to the air supply device and to the discharge device.

Abstract: A central air conditioning and ventilating system has an exterior air intake duct and a plurality of dampers for opening and closing air ducts. One damper is positioned in the exterior air intake duct and a second damper is positioned in the interior of a return air duct and a third damper is positioned in the interior return air duct escape air duct. The first damper can be opened while the second damper is closed and a third damper opened to convert the air conditioning system to a whole house ventilation system.

Abstract: An installation for processing wafers that includes fabrication units, which are located in a clean room, and includes a supply system for supplying and discharging operating substances for the fabrication units. The supply system has first supply lines and first discharge lines, in which operating substances that are heavier than the surrounding atmosphere are downwardly guided. The supply system has second supply lines and second discharge lines, in which the lighter operating substances are upwardly guided.

Abstract: A ventilation and air-conditioning system uses a first variable-air-volume system to cool and dehumidify fresh outside air and deliver it through a first duct to a mixing box located downstream. The system also uses a second variable-air-volume system to further cool and dehumidify recycled air and deliver it through a second duct to the mixing box where the fresh and recycled air are able to mix prior to ventilation into a room or office. The system uses a carbon dioxide sensor and a temperature sensor to provide feedback signals to a control system, which in turn regulates fan speeds and damper openings in order to provide optimal cooling and ventilation and to conserve energy when cooling and ventilation requirements are low.

Abstract: A filter retaining apparatus and method for installing a thicker filter in an existing conventional return air duct in a conventional heating and air conditioning system. The filter is commercially available but is thicker than one conventionally used in such systems. A thicker filter provides more efficient air filtration and has a longer life, thus, requires less frequent cleaning or replacement. The retaining apparatus is capable of retaining the thicker filter and is adaptable to the existing return air duct opening without modification of the existing opening or the grill cover. The apparatus has the same length and width dimensions as the existing thin filter and is mounted on the same landing surface. The greater depth of the apparatus extends into the air duct. Thus, from the room interior it is not possible to detect the use of the apparatus. The greater depth of the apparatus retains the thicker commercially available filter.

Abstract: An office air handling unit includes an intake, return and output system. The intake system transfers air from an external environment and through a preheating and cooling unit that regulates the temperature of the air entering the interior zone. The return system re-circulates air from the interior zone to the exterior zone through the use of a fan. The return system also regulates the temperature of the air entering the exterior zone by using a preheat unit and cooling unit. The output system allows for the transfer of air from the exterior zone to the external environment, re circulates the air back into the return system or re-circulates the air back into the intake system. The intake system allows for the transfer of air from the external environment to the return system to bypass the interior zone and provide fresh air to the exterior zone.

Abstract: A demand ventilation module for use with HVAC/R systems for ventilating inside space of a structure through an air pressure differential between return air and outside air. The demand ventilation module includes an integrated damper and an electronic control device capable of marking, setting, and/or storing air condition setpoints for ventilation activation. The electronic control device is configured to automatically control the activation of an actuator in conjunction with an inside sensor that measures air conditions in direct proportion to actual real-time air condition demands. A method for installing a demand ventilation module on return portions of HVAC/R systems may include: evaluating the return portion of an HVAC/R system to ascertain return air negative static pressure; and determining where to install the demand ventilation module on the return portion based upon a location corresponding with a range of return air negative static pressure.

Abstract: Methods and apparatus for recirculating air in a controlled ventilated environment. In one example, recirculation of air from one or more rooms in a multiple room ventilated environment having a common source of supply air is controlled such that minimum ventilation and thermal load requirements for each room are satisfied independently, so as to facilitate a reduction in the amount of fresh outside air required for the environment. In another example, the controlled airflows in each room may be based additionally on respective air quality levels of the air drawn from each room. In one aspect, if contaminants are detected in one or more rooms of the ventilated environment, the amount of air recirculated from a contaminated room back to the environment may be controlled based on a detected level of the contaminant and a dilution ratio of any returned contaminated air to the total uncontaminated air supplied to the environment.

Abstract: An air duct valve arrangement for use ain an air circulation system comprising an air handler unit and an air treatment unit. The valve arrangement being disposed to prevent short-circuiting of the air treatment unit, but not to hinder the operation of the air handler unit.

Abstract: The present invention provides an air handling system that receives air from a primary air source and distributes that air in a room defining an enclosed space. The system is mounted in the ceiling of the room and generally comprises first, second, third, and fourth inductor units interconnected downstream to the primary air supply and which define first, second, third, and fourth areas, respectively, wherein the induced air flows through each of the inductor units, through a series of converging nozzles, and into each units first, second, third, and fourth areas, respectively, and an air diffusing mechanism positioned adjacent to the first, second, third, and fourth areas which directs the induced air in first, second, third, and fourth directions, respectively. The inductors are generally arranged in a square configuration with the diffuser extending in the square space bound thereby.

Abstract: A demand ventilation module is provided for use with HVAC systems in order to ventilate inside space of a structure through an air pressure differential between return air and outside air. The demand ventilation module includes an integrated damper. The demand ventilation module can further include and an air restrictor plate that defines an air-restricting opening and an electronic control device capable of marking, setting, and/or storing air condition set-points for ventilation activation, and configured to facilitate ventilation control, economizer operation, and HVAC unit operation. The electronic control device is electrically connected to and controls the activation of an actuator in conjunction with inside and outside sensors that measure air conditions. The electronic control device can cause the actuator to automatically shift the damper in direct proportion to actual real-time air condition demands.

Abstract: A wall curb 10 for attachment to the exterior wall 32 of a building to removably secure a wall mounted HVAC unit 38 to the exterior surface 44 of the wall 32. The wall curb 10 serves to attach the supply air duct 34 from within the building to the supply air opening of HVAC unit 38 and to attach the return air duct 36 from within the building to a return air opening of the HVAC 38. An alternate embodiment of the invention 10A includes an outside air opening 60 with a controllable damper 62 for regulating the ratio of outside air verses return air from the building that enters the HVAC unit 38.

Abstract: An air circulation system is provided for a building having a plurality of zones to be heated, ventilated or cooled. The system includes an air circulating apparatus arranged to supply either heated, cooled or ventilated supply air to the various zones of the building via a plurality of supply ducts. The apparatus also draws return air from the zones via a plurality of return ducts. A damper is coupled to both the supply and return ducts of each zone, adjacent the air circulating apparatus, to balance the amount of supply and return air in each zone for reducing mixing of air between zones and stratification within a zone. Accurate and independent control of each zone in relation to the other zones in the building is thus permitted. The circular ducts are formed of sealed PVC or other suitable plastic material to improve the efficiency of the air delivery system both by reducing pressure losses and temperature losses conducted through the walls of the ducts.

Abstract: A demand ventilation module is provided for use with HVAC systems in order to ventilate inside space of a structure through an air pressure differential between return air and outside air. The demand ventilation module includes an integrated damper. The demand ventilation module can further include and an air restrictor plate that defines an air-restricting opening and an electronic control device capable of marking, setting, and/or storing air condition set-points for ventilation activation, and configured to facilitate ventilation control, economizer operation, and HVAC unit operation. The electronic control device is electrically connected to and controls the activation of an actuator in conjunction with inside and outside sensors that measure air conditions. The electronic control device can cause the actuator to automatically shift the damper in direct proportion to actual real-time air condition demands.

Abstract: The invention concerns a method and a device for variable flow heating for controlling ventilating fresh air room by room in a building. The invention is characterised in that said method provides sequential control of the air using a central management unit (48) programmed to be configured, either in a mode controlling the temperature levels in the main rooms (8) wherein it maintains the set temperature in said rooms and senses the possible complete closure of the (or all) the air outlets (5) supplying said main rooms, or at least if one of the main rooms is no longer supplied, in a mode controlling fresh air wherein it controls the opening of the air outlet(s) of each room not initially supplied during a time interval for making up for the lack of fresh air supply, and by closing the air outlets in all the other rooms during the same interval.

Abstract: A super-clean air device for the pharmaceutical sector, foodstuff sector, and biotechnology sector has at least one fan for conveying fresh air in a conveying direction into the clean room and for removing return air from the clean room. At least one filter is arranged downstream of the fan in the conveying direction. At least one heat exchanger is arranged upstream of the fan in the conveying direction. A common housing is provided and is designed to form a mounting module, wherein the at least one fan, the at least one filter, and the at least one heat exchanger are arranged in the common housing for ease of installation.

Abstract: An apparatus and method for controlling an induction motor having a variable frequency drive in a blower system so that the blower system provides a specific fluid flow. A start-up program causes the motor to ramp up to approximately a predetermined steady state speed. A required blower torque is calculated by operating on a table of blower constants, a selected flow rate and a motor speed which is read from a speed sensor in the motor/blower system. A developed motor torque is calculated by operating on a table of motor specific constants, a voltage-frequency index and the motor speed taken from the speed sensor. The calculated required blower torque is repeatedly compared with the calculated developed motor torque. The voltage-frequency index to the variable frequency drive is modified to force the developed motor torque to converge with the required blower torque in a steady state.

Abstract: An apparatus and method for controlling an induction motor having a variable frequency drive in a blower system so that the blower system provides a specific fluid flow. A start-up program causes the motor to ramp up to approximately a predetermined steady state speed. A required blower torque is calculated by operating on a table of blower constants, a selected flow rate and a motor speed. The motor speed is calculated by operating on a table of motor specific constants, a voltage-frequency index and a measured direct current bus current. A developed motor torque is calculated by operating on a table of motor specific constants, a voltage-frequency index and the calculated motor speed. The calculated required blower torque is repeatedly compared with the calculated developed motor torque. The voltage-frequency index to the variable frequency drive is modified to force the developed motor torque to converge with the required blower torque in a steady state.

Abstract: The present invention is an economizer that is capable of mixing outside air and inside air while incurring a significantly low pressure drop across the return air damper. In one embodiment, the economizer comprises a mixing chamber, a return air vent, and an outside air vent. The economizer further comprises a plurality of curved return air dampers moveable from an open position to a closed position to control the flow of return air to the mixing chamber. The economizer further comprises a plurality of straight dampers moveable from an open position to a closed position to control the flow of outside air to the mixing chamber. During operation of the economizer, a significantly lower pressure drop exists across the curved return air dampers than in conventional economizers thereby reducing the amount of energy needed to operate fans to maintain the desired air flow.

Abstract: Air-conditioning device includes a holder which is to be arranged against the wall of the room and is provided with a top wall, front wall, side walls, base and rear wall. An opening for the supply of fresh air form the environment is arranged in the rear wall. An air-inlet opening for the air from the room is arranged in the base, while an air-outlet opening is arranged on the top side. The supply of fresh air and inlet opening emerge in a first chamber in which a fan is arranged. A HEPA filter is connected to this chamber. A control device is provided in order to control the ratio between the fresh air flowing in and the air from the room in question.

Abstract: A climate control system includes an air evacuation and ventilation system thereof operable to withdraw air from an outflow air duct system and ventilate the withdrawn air to the outside prior to the system treating air withdrawn from an interior space of a building through an inflow air duct system. The air evacuation and ventilation system includes a ventilation duct having a first end in communication with an air outlet junction box and a second end having an opening located outside the building, an exhaust fan, supportably mounted within the junction box, for drawing air out of the outflow air duct system and into the ventilation duct, and a damper, supportably mounted within the junction box and pivotable between a closed position in which the damper prevents air from flowing into the ventilation duct and an open position in which air is drawn into the ventilation duct.

Abstract: A fan motor or blower unit attached and manufactured as part of the heating and cooling systems for homes and buildings or attached later to the furnace or air handler, which will vent out the HVAC ducts by removing the residing air. This air duct evacuation system will remove the unwanted warm or cool air from the building or structures air conditioning and heating duct systems, allowing for easier heating and cooling and more allergy friendly building or structure. The ADES will be on a relay switch or temperature controlled thermostat. The ADES will have a motor or blower unit able to pull the amount of the air per cubic feet per minute needed to vent the duct system. The main frame will have insulating stripping around the perimeter to prevent air leakage as well as a self closing and insulative exhaust flap doors. Surrounding the fan blades is a metal wire cage for safety of the blade operation.

Abstract: An air conditioning device has a controller, a fan motor, a by-path strangler, and a heat exchange pipe. The fan motor is disposed in front of the heat exchange pipe. The by-path strangler is disposed between the fan motor and the heat exchange pipe. The controller controls the by-path strangler. The controller has a central processing unit, an output control unit, a detect unit, and a sensor. The sensor senses an environmental detect value to the detect unit. The detect unit outputs the environmental detect value to the central processing unit. The central processing unit outputs a signal to the output control unit. The output control unit has a plurality of output junctions connected to a loading unit. The loading unit has a drive motor and two electric valves.

Abstract: A fan control system suitable for use in air moving applications has a pressure sensor responsive to an air pressure in an air duct for supplying a static pressure signal representative of the air pressure. A supply air flow sensor is responsive to an air flow in a supply air duct and supplies a supply air flow signal representative of the air flow in the supply air duct. A return air flow sensor is responsive to an air flow in a return air duct and supplies a return air flow signal representative of the air flow in the return air duct. A supply fan moves air in the supply air duct. The supply fan is driven by a supply fan motor. A return fan moves air in the return air duct. The return fan is driven by a return fan motor. A unitary volumetric air flow controller is connected to the supply fan motor and to the return fan motor.

Abstract: In an air conditioning apparatus, it includes a clean room, an air cleaning section, a cooling section and an air mixing section. The air cleaning section cleans air to supply to the clean room as cleaned air. The cooling section includes a plurality of cooling units and a plurality of non-cooling units. A plurality of cooling units cool air from the clean room to send out as cooled air. A plurality of non-cooling units sends out as non-cooled air from the clean room without cooling air. Each of the quantity of the cooled air and the non-cooled air is determined to compensate an amount of heat generated in the air conditioning apparatus and to reduce a pressure loss given to the air passing through the cooling section to a substantial minimum. The air mixing section mixes the cooled air and the non-cooled air to supply to the air cleaning section. The cleaned air is circulated through the clean room, the cooling section and the air mixing section to the air cleaning section.

Abstract: An air handling unit for a heating, ventilating and air conditioning system of a building has a plurality of exhaust fans. The exhaust fans are sequentially activated in response to the amount of air flowing into the air handling unit from outdoors. Thus the amount of air exhausted from the building approximates the amount of air drawn into the building through the air handling unit. This operation maintains the static air pressure within the building to acceptable levels.

Abstract: A damper blade system for positioning proximate a duct includes a housing with two, opposing sides; a first damper blade; and a second damper blade. The first damper blade is rotatably supported between the two sides of the housing, and one end of the first damper blade is coupled to a damper gear. The second damper blade is also rotatably supported between two sides of the housing adjacent the first damper blade, and one end of the second damper blade is coupled to another damper gear. The system further includes a support disposed on the side of the housing with the damper gears; a rack, having a plurality of teeth engaging the damper gears, movably disposed in the support; and a drive means for moving the rack along the support.

Abstract: Modular terminals for supplying conditioned air to spaces within buildings can be mounted and configured to provide improved heating, cooling, ventilation, and mixing of the supplied air with the space air. The flexibility in arranging the modular terminal components, such as air inlets, outlet grilles, dampers, and induction sleeves, permits for selectively altering the flow pattern, quality, volume, and velocity of air introduced into a space. The modular terminals can selectively draw air from a plenum, duct, or both. The terminals accommodate electrical wiring for office equipment, and also may accept flexible ducting to deliver conditioned air from a desktop or other furniture. The modular terminals also are part of a system and method for conditioning building spaces whereby a number of terminals are controlled in response to selected sensor readings. Various air handling units combine with the terminals to cycle the air and supply a source of filtered and conditioned air to the terminals.

Abstract: An arrangement for supplying air to a room, preferably a clean room, which is divided into zones (A, B, C) with different climatic requirements, comprises a first air treatment unit (11) for supplying air to a pressure chamber (5) which is shared by a plurality of zones and from which air is supplied to the various zones. The arrangement also comprises at least one mixing spaced (14) communicating with the pressure chamber (5) and a second air treatment unit (17). The mixing spaced is intended for mixing of the air from the first (11) and the second (17) air treatment unit. The mixing space also communicates with at least one of the zones (B) for supplying the mixed air to this zone (B).

Abstract: An air circulation system with standard and dual mode operations rapidly ventilates an enclosed area with fresh external air in the dual mode. In the dual mode of operation of the preferred embodiment, multiple barriers operate to create two airflow pathways. Two return air duct apertures are opened to expose the return air duct to an external air supply area via a fresh air duct. The fresh air duct includes an opening to the external air supply area and two extensions that are coupled to the return air duct apertures. The barriers simultaneously operate to block the return air duct between the two return air duct apertures to form two distinct return air duct segments. A central air unit and an exit fan, such as an attic fan, cooperate with the barriers to establish two airflow pathways through the return air duct segments.

Abstract: A system for detecting the presence of smoke within a building and providing means to remove the smoke, into the airspace above the ceiling thereby preventing or at least alleviating smoke inhalation, property damage, and allowing more time for the safe evacuation from the premises. The system is comprised of a conventional smoke detector which activates control means for raising and lowering a generally planar panel which is installed in a ceiling. Smoke is removed from the airspace below the ceiling to the airspace above the ceiling. An optional fan, remote fan relay, exhaust vent and back draft damper further aid in the exhausting of the smoke from the building. A fusible link in the control means protects the ceiling fire rating.

Abstract: A heating, ventilation, and air conditioning (HVAC) system uses unvitiated secondary return air to control the amount of a contaminant, such as carbon dioxide, in a space to maintain an improved air quality throughout the area served by the system. Preferably a terminal box controls the CO.sub.2 level in the space served by the box by selectively drawing air representative of air in other rooms to lower the CO.sub.2 level in the space being served. This reduces cost because air which is provided from other rooms within the building will require less total system heating or cooling in order to maintain the occupied space at the desired air quality.

Abstract: A damper blade system for positioning proximate a duct includes a housing with two, opposing sides; a first damper blade; and a second damper blade. The first damper blade is rotatably supported between the two sides of the housing, and one end of the first damper blade is coupled to a damper gear. The second damper blade is also rotatably supported between two sides of the housing adjacent the first damper blade, and one end of the second damper blade is coupled to another damper gear. The system further includes a support disposed on the side of the housing with the damper gears; a rack, having a plurality of teeth engaging the damper gears, movably disposed in the support; and a drive means for moving the rack along the support.

Abstract: An air outlet of an air conditioner is opened and closed by a door. A D.C. motor is operably connected to the door for opening and closing the door. The D.C. motor is supplied with D.C. power in response to the operation or stopping of the air conditioner.

Abstract: An over-the-range microwave oven includes air intakes in its bottom wall and fans disposed at an upper portion of the oven for drawing air through respective intakes. The fans are mounted in respective cases, each of which forms an air inlet and an air outlet. Each air inlet communicates with a respective intake, and the air outlets communicate with a common duct leading to a discharge grill. Filters extend across respective ones of the air outlets and are of substantially the same size as the respective air outlets.

Abstract: A room air conditioner includes an air inlet, an air outlet, a heat exchanger disposed between the inlet and outlet, and an air circulation fan. The inlet is opened and closed by motor-driven inlet vanes. The outlet is opened and closed by a vertically slidable motor-driven door. Air direction control vanes extend across the outlet for varying the direction of discharged air. Before the door is either opened or closed, the air control vanes are automatically swung upwardly to a clearance position to avoid interfering with movement of the door. When the inlet and outlet are to be closed, the inlet vane motor is actuated prior the door motor to ensure that the inlet and outlet are fully closed simultaneously, even though it takes longer for the inlet vanes to travel to their fully closed state. A sensor determines when the door reaches an almost-closed state, and the door motor continues to operate for a set period thereafter to ensure that the door becomes fully closed.

Abstract: A disk drive test chamber creates an environment for disk drives to be tested with an air circulation system that provides an even flow of air over each drive for equivalence in testing conditions. One method of providing equivalent air circulation is to have turning vanes inside air ducts to divert equal amounts of air over each shelf holding disk drives through identically sized apertures. The second method is to have apertures of varying sizes of 40, 50 and 70 percent opening per square inch in the air ducts to divert equal amounts of air. The temperature is maintained within 1/4.degree. C. of the set point by a controller through a system of heaters, air pumps, air ducts, insulation, vents, a motorized damper and an exhaust fan. The heater generates heat to simulate the actual heat of running conditions of disk drives. The pumps send air up the side air ducts and down the center air duct. The chamber has two safety features to prevent damage to the disk drives from over temperature.

Abstract: An air exchange and cleaning system for building enclosures, particularly indoor firing ranges, which removes particulate matter, such as lead and other heavy metals, and gun powder residues and gases from the enclosure atmosphere. An air handler unit includes a particulate matter separator and five stages of filtration which filter both powder and gases from the air. Ducts connect the air handler unit to the enclosed area of the building. The system includes a control system which starts the air handler unit, checks the status of the filters and other operating systems of the air handler unit and ensures that a required minimum negative pressure within the enclosure is achieved before signals are sent to permit operations within the enclosure. In the example of an indoor firing range, the air handler unit and duct system purges the range of possibly contaminated air, checks for satisfactory system operation and ensures a predetermined negative pressure is reached before turning on lighting to the range.

Abstract: A damper blade system for positioning proximate a duct includes a housing with two, opposing sides; a first damper blade; and a second damper blade. The first damper blade is rotatably supported between the two sides of the housing, and one end of the first damper blade is coupled to a damper gear. The second damper blade is also rotatably supported between two sides of the housing adjacent the first damper blade, and one end of the second damper blade is coupled to another damper gear. The system further includes a support disposed on the side of the housing with the damper gears; a rack, having a plurality of teeth engaging the damper gears, movably disposed in the support; and a drive means for moving the rack along the support.

Abstract: A method of preparing an installation of channel using units in several rooms on the one and same floor so as to allow a subsequent completion of units with multiple channel elements. Onto a flooring support between a distributing central unit and the rooms on the floor, the flexible channel elements which are enclosed in an exterior casing, are enclosed. These channel elements are a) a separate channel or conduit for the flow of a hot or cold brine to and from radiators in the rooms, b) channels for supplying electricity and/or for communicating with the units; and c) a channel space for fresh air between the elements. The floor is then finished to cover the multiple channel elements.

Abstract: A control system for controlling an air handling unit. The control system links the position of an exhaust air damper and a recirculation air damper so as the exhaust air damper is opened, the recirculation air damper is closed the same amount, and vice versa. An outside air damper remains completely open at all times. The relative positions of the exhaust air damper and the recirculation air damper control the amount of outside air that is emitted into the air handling unit through the outside air damper. For each of the control states of heating with minimum outside air, cooling with outside air, mechanical cooling with maximum outside air, and mechanical cooling with minimum outside air, the outside air damper remains completely open, and the position of the exhaust air damper and the recirculation air damper are controlled based on a particular state. Sequencing strategies are employed for transitions between the control states that utilize these positions of the dampers.

Abstract: A bypass system is incorporated into a roof curb to permit selective partial or complete deactivation of at least one section of a heat pipe of an air conditioning system thereby 1) to permit optimization of the sensible heat ratio of the air conditioning system for prevailing environmental conditions and, 2) to prevent moisture from condensing onto the evaporator or cooling section of the heat pipe and subsequently dripping into the return ducts of the air conditioning system. The bypass system is characterized by a bypass duct located adjacent one of the sections of the heat pipe and a bypass device which selectively channels at least some of the air which would otherwise flow through the controlled section of the heat pipe through the bypass duct instead. In its simplest form, the bypass device may comprise a single damper or the like positioned within the bypass duct.

Abstract: A method for controlling combustion air in a boiler plant, where combustion air is supplied into a boiler located in a boiler building, comprises the steps of determining a ratio of air flow inside the building to air flow outside the building on the basis of at least the temperature of the outside air and of a load of the boiler; taking a first air flow from inside of the building in accordance with the ratio; taking a second air flow from outside the building in accordance with the ratio; the second air flow being at a certain temperature; and supplying a combined combustion air flow including the first and second air flows, in accordance with the ratio, to the boiler. Also an apparatus is provided for controlling combustion in boiler building permitting it to achieve the above steps.

Abstract: The invention relates to a ventilation device. Provision is made that the air propulsion plant (20) conveys at least a portion of the air in an air circulating mode by means of at least one variable volume chamber (6) in a pulsating manner at a very low frequency, with the chamber being connected to the room (2) by at least one air passage (21).