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: An air conditioner includes an air outlet for discharging temperature-conditioned air. Horizontal and vertical blades extend across the air outlet and are pivotably adjustable for controlling the up/down and right/left directions of air flow, respectively. The blades are pivotable by means of motors. A manually manipulable control panel enables a user to select between automatic and manual control over the positions of the blades. If automatic control is selected, then the horizontal and/or vertical blades are continuously pivoted within a predetermined angle. If manual control is selected, a target position for the horizontal and/or vertical blades is chosen, wherein a detector senses a current position of the blades and stops the motor(s) when the target position has been reached.

Abstract: A pair of variable air volume fans and a set of primary and exhaust air diffusers are in atmospheric communication between a supply of ventilation air that employs the principles of thermal displacement ventilation for purging a designated smoking area of smoke pollutants and the outside atmosphere for receiving the purged polluted air. The volume of ventilation air supplied to the designated area and the volume of air exhausted from the designated area is based upon air quality demand requirements and is determined by a microprocessor coupled to a gas sensor disposed within the designated smoking area.

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 ventilation display system determines when a ventilation system has remained in recirculation mode for a predefined time, and in response generates a stale air alert message inside the cab of a truck. The system can generate messages alerting the driver that the HVAC system has switched into recirculation mode, and alerting the driver that the recirculation mode has remained active for the predefined time. When equipped with a CO.sub.2 sensor, the system can generate air quality messages based on either the status of the recirculation mode or the level of CO.sub.2 in the cab of the truck or both.

Abstract: An indoor environmental conditioning system and a method for controlling the circulation of non-conditioned air. The system comprises a conditioning source, air distribution source and air distribution conduit. The air may be propelled at at least two different flow rates.

Abstract: A motor vehicle ventilation system having a recirculation or air input mode in which when the rate of change of a signal from an outdoor gas pollution sensor exceeds a threshold limit, the system is adjusted to the recirculation mode.

Abstract: A ventilator which includes a male member is telescopically received within a female housing. The male member is longer than the passage in the female housing such that the male member protrudes from the passage of the female housing. Radial air flow passages are positioned at both the first end and the second end of the male member. Relative movement of the male member and the female housing in a first direction diminishes the area of radial air flow passages exposed to air flow from the first end of the female housing while increasing the area of the radial air flow passages exposed to air flow from the second end of the female housing. Relative movement in a second direction diminishes the area of radial air flow passages exposed to air flow from the second end of the female housing while increasing the area of the radial air flow passages exposed to air flow from the first end of the female housing.

Abstract: An apparatus and method for space pressure control in high containment laboratories. The system comprises a volumetric air flow controller and a differential pressure controller. The differential pressure controller couples to the volumetric air flow controller. To establish negative space pressurization in the laboratory, the differential pressure controller generates a variable offset signal for volumetric operation. In response to the offset signal, the volumetric air controller controls the ducted supply air to the laboratory at a set shortfall compared to the ducted exhaust air flow. The shortfall of ducted supply air creates a negative pressure which is also sensed by the differential pressure controller. The differential pressure controller reduces the variable offset signal to zero once the desired negative pressure level is attained. To maintain the negative pressure level, the supply and exhaust air flow rates must remain equal.

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: An air conditioning unit is provided with a high capacity filtration system for removing pollutants from supply air, typically return air which has been recirculated from the conditioned area. A filter bypass passage and suitable flow control devices are provided so that supply air, typically fresh outdoor air, may be routed around the filtration system when minimal or no filtration is required. An air quality detector samples the air quality and positions the flow control devices to effect the most cost efficient operation of the air handling unit under the given operating conditions.

Abstract: A ventilation system for use, in example, on a spray booth or paint stripping enclosure, in which variable speed fans (or equivalent) are employed, and controlled by a sensor so that the flow rate exhausted from the booth (and directed either to an emission control device or vented to atmosphere) is continually adjusted to minimize the exhaust flow rate from the enclosure. The remainder of the ventilation air is recirculated back into the enclosure. An analyzer located in the recirculation duct continuously monitors the concentration of hazardous constituents present in the recirculation stream, and transmits this data to a central controller, which controls the ventilation fan systems. The central controller controls the recirculation duct and exhaust duct fan systems to achieve the highest recirculation rate possible, yet also maintain constituent concentrations in the recirculation duct at a safe level.

Abstract: Mixing section for outdoor air and return air in an air-conditioning apparatus, the mixing section being positioned between a supply duct supplying outdoor air into a room and a return duct removing exhaust air from the room for mixing outdoor air and return air. The supply and return ducts comprise adjusting devices for adjusting the air flows. To control the air flows at different mixing ratios and to make the mixing more efficient, guides are provided after the adjusting devices of both the supply device and the return device in a mixing space so as to divide the air flows passing through the adjusting devices into a plurality of separate interlapping air jets crossing each other.

Abstract: A system for circulating ventilating air in a space includes a supply air chamber configured for communication with a supply duct, a return air chamber configured for communication with a return air duct, and an outside air chamber configured to receive outside air from an outside air intake. The outside air chamber includes an outside air damper having a plurality of settings for varying outside air flow volume in the outside air chamber. The outside air damper establishes a predetermined relationship between each outside air damper setting and the outside air flow volume. The outside air damper establishes each setting in response to a damper control signal. The system further includes a mixed air plenum in communication with the return air chamber and the outside air chamber and a fan positioned between the mixed air plenum and the supply air chamber, the fan supplying a constant volume of air to the supply air chamber in response to a fan control signal.

Abstract: An airhouse for supplying conditioned air to the interior area of an enclosed building. The airhouse incorporates one or more blowers having variable speed controllers enabling them to be operated at variable volumetric flow rates. The airhouse housing includes variable area dampers for controlling the inlet of outside or building return air. A dedicated controller is provided for adjusting the inlet areas of the two inlet pathways to provide a constant flow velocity through a direct fire burner through a range of blower volumetric output settings. In addition the units may include variable area diffuser units which tend to maintain constant discharge velocity pressure at various blower volumetric flow rate settings. In addition various control and operating strategies are provided for the individual airhouse units and a distributed array of such units in a large building structure controlled by a central computer.

Abstract: An air conditioning unit is provided with a high capacity filtration system for removing pollutants from supply air, typically return air which has been recirculated from the conditioned area. A filter bypass passage and suitable flow control devices are provided so that supply air, typically fresh outdoor air, may be routed around the filtration system when minimal or no filtration is required. An air quality detector samples the air quality and positions the flow control devices to effect the most cost efficient operation of the air handling unit under the given operating conditions.

Abstract: A control is provided for a facility which has at least one pressurized room which control facilitates the making of selected changes in offset between the room and a space external thereto while maintaining a desired air flow balance. This is accomplished at least in part by making changes in the air flow for the external space in connection with such offset changes.

Abstract: An apparatus and method for thermostatically controlling the operation of a multiple speed fan and light assembly by inputting a desired temperature range and airflow direction for each fan speed and by inputting a single number for controlling the on time and duration of the light assembly. A temperature sensor determines an initial room temperature, an input device enters a temperature set-point corresponding to each of the fan speeds, a processor stores the temperature set-points corresponding to each of the fan speeds from the input device, receives the temperature signal and uses the temperature signal and the temperature set-points to determine a desired fan speed, and a fan driving device changes the initial rotation speed to the desired fan speed in response to the processor and thereby automatically controls the fan speed.

Abstract: A method and apparatus for controlling the environment within an enclosed space is provided. The apparatus monitors environmental variables, and responsive to the values of the environmental variables, estimates the rate at which a gas is being generated within the enclosed space. The apparatus generates control signals to control devices based on the rate at which the gas is being generated within the enclosed space. In the preferred embodiment, the apparatus estimates the rate at which carbon dioxide is being generated in the enclosed space. Based on the estimated carbon dioxide generation rate, the apparatus may be configured to control an HVAC system, a comfort control system, lights, alarms or other devices.

Abstract: An airhouse for supplying conditioned air to the interior of an enclosed building. Matched twin blowers symmetrically arranged within the airhouse enclosure are operated in unison to insure a balanced air flow into the airhouse and through the blowers. A burner unit mounted intermediate the blowers is flanked by matching outside air inlets having controllable dampers, preferably of a canister-type, operable in opposition. A building return air inlet located midway between the blowers likewise has canister-type dampers operable in opposition. The blowers may be independent and operated at the same speed by separate drive means, or they may be mounted on a common shaft operated by a single drive means. A controller may be provided for varying the speed of the drive means. In one embodiment dampers may be provided for the building air outlets along with dampered openings from the blower enclosures to the external atmosphere for rapidly expelling contaminated air from the building interior.

Abstract: A cooling/heating apparatus having an automatic ventilating function and its method switches the ventilating function and the cooling/heating function in response to the pollution state of room air and maintains the room air in a pleasant state. The apparatus and method rotates the cooling/heating fan and the ventilating fan to be mutually supplemented and completed by the output of a gas sensor which changes its resistance value in response to the air pollution state within a room. The ventilating fan is rotated instead of said cooling/heating fan when the room air is polluted and ventilates the polluted air within a room.

Abstract: An apparatus and method indirectly determines the amount of outside air introduced into the ventilation system of a structure to control the indoor air quality in the structure. Test gas concentrations, preferably carbon dioxide concentrations, are measured for return air, outside air and mixed (supply) air. The flow rate of mixed air is measured. The volume of outside air introduced into the system is determined through use of the test gas concentration measurements without directly measuring the volume or flow rate of outside air. Preferably, a single sensor is utilized to measure each of the trace gas concentrations in the return air, outside air and supply air, and the various measurements sequentially multiplexed to a controller. Moreover, for calibrating the apparatus, a return air sensor is calibrated to the outside air and a mixed air sensor is calibrated to the outside air or the return air to eliminate inaccuracy due to sensor drift.

Abstract: A system for maintaining atmospheric conditions in an enclosed building within desired parameters and rapidly evacuating abnormally high amounts of airborne pollutants from localized areas of the building. Conditioned air, including sufficient outside air, is continuously admitted to the building interior from a plurality of air handling units disposed about the building to maintain the interior of the building under a slight positive pressure throughout. The air handling units, at least in areas where concentrations of airborne contaminants are generated include, in addition to outside air and building air inlets and a building air outlet, an outlet exhausting to the outside. Sensors and/or scanning units located throughout the building monitor various atmospheric conditions and transmit signals indicative of the noted conditions to a central computer.

Abstract: An air quality and temperature responsive air conditioning system wherein modules are employed to precondition the air for humidity control, to heat and cool the air, and to bypass the supply air in excess of the demand of a multiplicity of comfort zones with thermostat control, and featuring a bypass module characterized by parallel ducting, one ducting which is restricted by a damper responsive to a supply air back pressure sensor, and one ducting which is opened by a damper responsive to an air quality sensor.

Abstract: An apparatus and method indirectly determines the amount of outside air introduced into the ventilation system of a structure. Carbon dioxide concentrations are measured for return air, outside air and mixed air. The flow rate of mixed air is measured. The volume of outside air introduced into the system is determined without directly measuring the volume or flow rate of outside air. For calibrating the apparatus, a return air sensor is calibrated to the outside air and a mixed air sensor is calibrated to the outside air or the return air to eliminate inaccuracy due to sensor drift.

Abstract: An air quality conditioning system for adjusting an environmental air quality in an accommodation space comprises; a detection device for detecting the air quality; another detection device for detecting the temperature and humidity; a signal processor for identifying the causes for the change in the air quality of the accommodation space based on the outputs of said detection devices, and also determining the degree of the change based on the discomfort degree data for the air quality, with another function of correcting the outputs of said detection means for the temperature and humidity.

Abstract: An air conditioning apparatus comprises an automatically controlled mixing box for an air conditioning system wherein a triple inlet mixing box has a cold air inlet, a hot air inlet, a return air inlet, and a fan for inducting and disbursing the air mixed therein. Thermostatic motors regulate the first and second dampers having a configuration which controls opening or closing of the hot air inlet, the return air inlet, and the cold air inlet in such a manner that the air mixture may be regulated from cold to neutral to hot without any direct mixture of the cold air and the hot air at any time. The fan draws in the air from the open or partially open inlet openings to mix the same and discharge the mixture to the room. Several fan-powered mixing boxes may be incorporated to create a multizone system with each zone regulated by a thermostat to mix the return air with hot or cold air to supply the desired zone temperature.