Abstract: A method of monitoring a HVAC system to detect erroneous sensor installation. The method includes determining whether a circulation fan has been operational for a first predetermined time interval. If the circulation fan has been operational for the first predetermined time interval, determining whether a cooling demand is present. If the cooling demand is present, determining whether the HVAC system has been conditioning air for the first predetermined time interval responsive to the cooling demand. If the HVAC system has been conditioning the air for the first predetermined time interval, determining whether a difference between an indoor air temperature value corresponding to an enclosed space and an air temperature value from a discharge air temperature (DAT) sensor is greater than a predetermined temperature value.

Abstract: This disclosure provides a control method and control system for two or more air-conditioning water chilling units, and air conditioning system. The control method includes: receiving at least one standby request generated by at least one air-conditioner water chilling unit of the two or more air-conditioning water chilling units based on a standby condition; determining whether or not two or more standby requests are received; generating standby sequence numbers of the air-conditioning water chilling units that send the standby requests according to the standby requests in case where two or more standby requests are received; and closing the air-conditioning water chilling units that send the standby requests according to a preset rule based on the standby sequence numbers.

Abstract: In an embodiment, a circuit for providing a mixed air temperature signal is provided. The circuit has a temperature input to an economizer controller, an air temperature sensor, a false air temperature device, and a switching device. The switching device has a switch and a switch actuating device. The switch connects the temperature input to the air temperature sensor when the switch is in a first state. The switch connects the temperature input to the false air temperature device when the switch is in a second state. The switch actuating device places the switch in the first state when a mechanical cooling signal is not sent. The switch actuating device places the switch in the second state when the mechanical cooling signal is sent.

Abstract: An electronic expansion valve (EEV) is employed in refrigeration systems to regulate the flow of refrigerant through an evaporator. The position of the EEV is controlled through a first control loop that generates a first position signal based on superheat feedback associated with the refrigeration system, and a second control loop that generates a second position signal based on pressure feedback associated with the refrigeration system. The larger of the first position signal and the second position signal is selected to control the position of the EEV value, and the selected position signal is provided in feedback to both the first control loop and the second control loop.

Abstract: An air unit includes a coil located in an air stream of the air unit. The air stream has an air flow direction. An air temperature sensor is located in the air stream of the air unit and is further located downstream, relative to the air flow direction, of the coil. A smart valve is in fluid communication with the coil and in electronic communication with the air temperature sensor. The smart valve is operable to control an amount of water flow through the coil. The smart valve receives a temperature setpoint signal, and the smart valve is programmed to modulate a valve position of a smart valve actuator based on the temperature setpoint signal and based on a signal from the air temperature sensor.

Abstract: An air conditioning system having a supply fan for supplying air to a supply duct; a fan motor for driving the supply fan; and a controller for controlling a speed of the fan motor, the controller operating the fan motor at a first speed in a first mode, a second speed lower than the first speed in a second mode and a third speed lower than the second speed in a ventilation mode.

Abstract: An operating terminal that is capable of controlling an air conditioner including an indoor device and an outdoor device. The operating terminal includes a display unit that displays at least state information of an air conditioner, a memory that stores therein setting information recorded on an outdoor/indoor control substrate, a communication unit that performs information communication with the indoor device, and an information processing unit that reads setting information set in the outdoor/indoor control substrate through the communication unit, records this setting information 32a in the memory, and causes the display unit to display the setting information.

Abstract: A method for measuring HVAC efficiency is disclosed which may be used to test various heat transfer or passive elements within a HVAC system to determine whether any element, such as a cooling coil, heating coil, filter or mixer, is operating at an acceptable efficiency when compared to design specifications or previously established standards. The method may also be used to easily determine volumetric flow rate of air through the system at various points.

Abstract: An air heating and cooling system includes (1) a heat pump, illustratively devoid of auxiliary electric resistance type air heating structure, operative to provide refrigerant-based heating or cooling of air being delivered to a conditioned space, (2) a fuel-fired modular blower selectively operable to generate combustion heat, and (3) a control system associated with the heat pump and the modular blower. The control system has a heat pump thermostat electrically connected to a modular blower control and operative to transmit to the modular blower a first signal indicative of heating operation of the heat pump, and a second signal indicative of a need for alternative heat during a heating demand cycle. The modular blower is operative, in response to receiving both signals, to provide combustion-based air heating in place of refrigerant-based heat pump air heating.

Abstract: According to the embodiment, the air conditioning system for a server changes air conditioning control target values within a certain range when outside air and return air both have higher specific enthalpy than the target state and hence the mixed air of the outside air and the return air cannot be adjusted to air in the target state.

Abstract: An HVAC system controller has at least one processor configured to monitor at least one of a first humidity and a first temperature of a first air volume sensed by a first sensor and at least one of a second humidity and a second temperature of a second air volume sensed by a second sensor, configured to calculate an environmental metric, and configured to determine whether mixing the first air volume with the second air volume can cause the environmental metric to conform to a first threshold requirement.

Abstract: Discussed generally herein are systems and methods for comfort level regulation in a building. A comfort level regulation system for a building can include a plurality of air intakes configured to draw air into the building, and a processor configured to open the one or more air intakes of the plurality of air intakes as a function of an orientation of the building, the location of the air intake relative to the orientation of the building, air temperatures inside and outside the building, and humidity inside and outside the building.

Abstract: An energy recovery ventilator control system is disclosed that is operable to be energized by electrical connection to a heating and cooling system including a thermidistat in fluid communication with each of an intake air duct and an exhaust air duct. The energy recovery ventilator control system is operable to regulate air temperature and humidity within a building using a temperate and humidity control scheme.

Abstract: An apparatus and a method for controlling an HVAC system in a building are provided. The apparatus may include: (a) sensors provided at different locations inside and outside of the building each providing an electrical output signal representative of a measured condition, wherein the sensors sense two or more of the following conditions: temperature, carbon dioxide and volatile organic compound conditions; (b) an embedded computer receiving the electrical output signals of the sensors and based upon which provides a plurality of output control signals; and (c) HVAC actuators operating in accordance with the output control signals, wherein the HVAC actuators affect a climatic condition or an air quality condition at one or more locations where the sensors are located.

Abstract: The present disclosure provides a method for controlling an economizer of an HVAC system. The economizer has an outside air stream of incoming outside air, a return air stream of return air, and a mixed air stream of mixed incoming outside air and return air that is provided to the cooling unit of the HVAC system. The economizer also includes one or more controllable dampers for controlling a mixing ratio of incoming outside air to return air in the mixed air stream. The control method includes positioning the one or more controllable dampers in first and second configurations such that the mixed air stream has first and second mixing ratios of incoming outside air to return air in the mixed air stream. The method also includes recording first and second measures related to the temperature of the mixed air stream when the dampers are in each of the first and second configurations. First and second measures related to other parameters of the mixed air stream may be recorded as well.

Abstract: Supervisory controllers, and methods, for use in a coordinated IAQ and economizer system. Various control objectives are defined and met. Some illustrative control objectives include economizer control, sequencing of economizer free cooling with compressor driven cooling, indoor air quality and FAV aims, demand ventilation settings, system protection from low temperatures, and smoke, supervisory and fault tolerance commands. The controller may be self configuring. A tiered fault tolerant controller is also provided. An illustrative controller is configured to determine whether various system sensors and devices are operational. The illustrative controller is also configured to perform a first method when all system sensors and/or devices are functioning, and at least a second method in response to sensor or device failures. The supervisory controller may include integrated economizer control, or may be configured as a separate controller.

Abstract: The present invention relates to a color space quantization descriptor structure for performing quantization of a color space in order to search a multimedia based on contents when multimedia feature information is color information, particularly when the multimedia feature information is the color information and the search is about a moving image or a still image, the color space quantization descriptor structure according to the present invention has a tree structure divided into a plurality steps of superior color spaces and subordinate color spaces, and the tree structure recursively comprises a plurality of subordinate color spaces. Accordingly, the present invention can improve performance of a still image and a moving image search apparatus, perform the quantization of a n dimensional color space such as a H, S, V, RGB, HMMD color space etc., and perform the different step quantization corresponding to each feature.

Abstract: An air conditioning system using enthalpy of the outside air controls automatically the opening rates of the outside air inflow damper and the inside air discharge damper to control automatically an amount of air flowing from the outside of a building to the inside and an amount of the air discharging from the inside to the outside depending on the difference between enthalpy of the outside air and enthalpy of an discharge air, and an amount of CO2 detected the inside of the building. All of the control status is identified and grasped at sight by controlling all of the driving devices and setting them in a central main control system.

Abstract: A method and system for controlling a heating, ventilating, and air conditioning unit is provided. The system includes a conditioning unit having a heating stage, a cooling stage, and a fan. The conditioning unit operates in an active mode where one of the heating stage and the cooling stage is activated to condition air in an enclosure. The conditioning unit also operates in a ventilation mode to provide supply air to the enclosure. A supply temperature sensor is provided to sense the temperature of the supply air. A central control operates to activate one of the heating stage and the cooling stage when the conditioning unit is operating in the ventilation mode and the temperature of the supply air is outside of a predetermined range.

Abstract: An enhanced controller for an air conditioning system incorporating mechanical cooling equipment and an economizer, the enhanced controller including circuits for producing signals indicative of commanded changes in temperature of air admitted into the air conditioned space and of a non-temperature parameter, such as carbon dioxide concentration, of air within the space. The signals are supplied to a logic circuit which produces a ventilation damper control signal based on which of the temperature and non-temperature parameters requires greater change. Freeze protection, and maximum and minimum damper position circuits override the basic damper control signal to avoid excessively low space temperatures and to provide air exchange limits.

Abstract: The present invention is a system for controlling the quality of air in a building. The system includes a sensor disposed for sensing the air quality in a building. Upon a sensing of an air quality problem, the system issues a command to draw in additional outside air into the building to alleviate the problem. The issuing of such command can be made conditional on a measurement of outside air temperature. The flow of additional outside air may be limited or avoided altogether where drawing in additional outside air would adversely affect the inside air temperature. Additional air can be drawn into a building, for example, by opening an economizer, activating a fan system, or by increasing a pressure setpoint in a supply air duct.

Abstract: The description relates to a device for air conditioning control in an air-conditioned room containing textile machines, especially circular spinning and spooling machines, with an air feed and an air discharge duct connecting the air-conditioned room to the air conditioning unit. A first set of sensors for measuring the temperature and relative humidity of the air in the room is connected for the control purposes to a first regulating circuit, and a second set of sensors for measuring the temperature and relative humidity of the feed air is connected for control purposes to a second regulating circuit. The first and second regulating circuits are connected in cascade, the first regulating circuit supplying a reference value to the second regulating circuit which controls the adjusting components of the air conditioning unit.

Abstract: A method of and system for regulating mixed air in an air-conditioning system of a motor vehicle provides for feeding fresh air and/or recirculated air to the air conditioning system. For optimizing the energy consumption for automobile air-conditioning systems, the specific enthalpy of the fresh air and the specific enthalpy of the recirculated air and/or of a mixed air are determined and, after a comparison of the specific enthalpies, a feed of fresh air and recirculated air is so adjusted that the mixed air has the specific enthalpy which is in each case most favorable from an energy standpoint.

Abstract: An apparatus for ventilating the crawl space of a structure, comprising an exhaust fan in a housing adapted to at least partially occlude an aperture in a foundation wall of a structure and oriented to, upon receiving an appropriate stumulus, exhaust crawl space air through said aperture to outside the structure, a temperature sensor and a relative humidity sensor for sensing the respective temperatures and relative humidities of crawl space air and of outside air, and for transmitting respective stimulus dependent thereon to a programmed computer, said computer also adjusting said relative humidity stimulii for temperature-dependent deviation, then determines the absolute moisture differential from said adjusted stimulii and compares said differential to a pre-set minimum absolute moisture differential parameter for ventilation activation, said computer also functionally connected to said fan for controlling the activation thereof

Abstract: A control for a fan has a temperature sensor and a humidity sensor the outputs of which are supplied to a processor. The processor switches on the fan when certain temperature and humidity conditions are met. The processor turns on the fan in response to an increase in temperature and humidity, a larger increase in humidity being required for a smaller increase in temperature. The fan is also turned on when humidity rises above a certain threshold value, which is lower for higher temperatures.

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 low-cost, accurate enthalpy sensor is described. The invention provides an on/off output which reflects the result of a comparison between the enthalpy level of a space and a predetermined setpoint. The sensor combines a signal representative of humidity with a signal representative of temperature to create a signal representative of enthalpy. The signal representative of enthalpy is compared with a predetermined setpoint to determine if the enthalpy level is above or below the setpoint. An output is then produced which indicates whether the output representative of enthalpy is above or below the predetermined setpoint.

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.