Abstract: For monitoring and controlling an HVAC system which comprises one or more fluid transportation systems with a plurality of parallel zones, a plurality of operating variables of the fluid transportation systems are received (S1) from devices of the HVAC system. Temporal courses are determined (S3) for the operating variables. Interdependencies are determined (S4) between the temporal courses of the operating variables. Depending on the interdependencies, the operating variables and their associated devices are grouped (S5) into different sets which each relates to a different section of the HVAC system and includes the related operating variables and associated devices. The sets are used (S6) to control the devices of a particular section of the HVAC system and/or to generate a fault detection message regarding one or more of the devices of the particular section of the HVAC system.

Abstract: A diffuser assembly for a heating, ventilating, and air conditioning (HVAC) system includes a housing having an outer frame and an inner frame disposed within the outer frame. The outer frame includes an inlet configured to receive an air flow. The inner frame forms a first flow path for the air flow through the housing between the outer frame and the inner frame. The inner frame defines a second flow path for the air flow through the inner frame. The diffuser assembly also includes a damper assembly configured to transition between a first configuration to enable discharge of the air flow from the housing via the first flow path and a second configuration to enable discharge of the air flow from the housing via the second flow path.

Abstract: An HVAC system for enhanced source-to-load matching without sacrificing airflow delivery in low load structures. Embodiments of the present disclosure provide for an HVAC system for enhanced source-to-load matching in a low load environment, i.e. dwellings with a BTU/hour capacity of less than 18,000. Prior art HVAC equipment is oversized for dwellings with a BTU/hour capacity of less than 18,000 that are insulated to minimum code requirements. Embodiments of the present disclosure provide for an HVAC system that separates the delivery of airflow (CFM) output from that of the BTU capacity output, thereby enabling a distributed delivery system for optimal source-to-load matching without sacrificing airflow delivery in low load environments. The source-to-load matching enabled by the present disclosure ensures optimal indoor air quality, enhanced comfort for occupants of the dwelling, and approximately a 60% reduction in heating and cooling costs when compared to prior art HVAC systems.

Abstract: In order to enable a uniform air-conditioning of the entire room, a fixed air blowing portion 75 and movable air blowing portions 77 on both sides thereof are provided on a decorative panel 70 as an air blowing part 74, and the movable air blowing portions 77 can rotate about an axis orthogonal to the panel surface or the ceiling surface of the decorative panel 70.

Abstract: A ventilation fan includes a body unit, which has a fan disposed in a body case and a fan controller operable to control an air volume of the fan. The ventilation fan also includes a sensor module having an indoor environment detecting sensor and a module controller operable to control a detecting operation of the indoor environment detecting sensor. The body unit has a module mount on which the sensor module is mounted and another sensor module can be mounted in place of the sensor module. The module mount is connected to the fan controller. The module controller outputs detection information obtained based on a detection result of the indoor environment detecting sensor to the fan controller, which in turn controls the air volume of the fan based on the detection information inputted thereto.

Abstract: A method is provided for controlling an HVAC system. The method includes receiving zone airflow target values for zones of a conditioned space. The method includes accessing a duct model including a first term that describes a flow factor for a zone damper as a nonlinear function of damper position, and a second term that describes zone airflow as a function of the flow factor and a branch pressure across zone-specific branches of an air circulation path. The method includes applying the zone airflow target values to the duct model to determine a damper position set, and actuating zone dampers to respective damper positions of the damper position set. The method may also include determining a value of total airflow to achieve the zone airflow target values with a total pressure target, and causing a fan to provide conditioned air with the value of the total airflow.

Abstract: An electric blower system is described. The blower system includes a blower, an airflow system, a sensor, and an electric motor. The electric motor includes a motor controller. The motor controller is configured to operate the motor at a first torque and a first speed to generate a first airflow, determine a first airflow value wherein the first airflow value, the first torque, and the first speed define a first benchmark data point. The motor controller is also configured to operate the motor at a second torque and a second speed to generate a second airflow and determine a second airflow value wherein the second airflow value, the second torque, and the second speed define a second benchmark data point. The motor controller is further configured to generate an operating profile for the blower system defining torque, speed, and airflow points for different system resistances.

Abstract: An air-conditioning apparatus includes a fan to send air to an air-conditioned space through a duct, a current measurement unit to measure a value of a current applied to a motor as a motor current, an inlet temperature measurement unit to measure a temperature of air flowing into the duct as an inlet temperature, and a controller to control the fan. The controller includes a memory storing current characteristic data associating the motor current and a rotation frequency of the motor with an external static pressure. The controller performs a correction process based on the inlet temperature to the motor current to obtain a control current, estimate the external static pressure by comparing the obtained control current and the rotation frequency of the motor with the current characteristic data, and control a rotation frequency of the fan, on the basis of the estimated external static pressure.

Abstract: Discussed is an air conditioner disposed in an indoor space. The air conditioner includes a sensor, a memory configured to store a plurality of learning results respectively corresponding to a plurality of members, and a processor configured to identify at least one member that is present in the indoor space among the plurality of members by using data acquired by the sensor, control operation of at least one of a compressor, a fan motor, or a vane motor based on the learning result corresponding to an identified member so as to adjust a set value including at least one of a set temperature, an air volume, or a wind direction, and update the learning results by using feedback on the adjusted set value.

Abstract: An artificial intelligence (AI) device for guiding an arrangement location of an air cleaning device includes a memory to store an air cleaning device arrangement model to infer the arrangement location of the air cleaning device based on information on fine dust in a house and a processor configured to acquire information on a map of the house and information on fine dust distribution in the house, and to determine the arrangement location of the air cleaning device based on the information on the map and the information on the fine dust distribution, by using the air cleaning device arrangement model.

Abstract: An air blowing device includes a housing, a partition plate, an air blower, dampers, and a controller. The housing has a first side surface and a second side surface. The first side surface has inlet A and outlet A. The second side surface has inlet B and outlet B. The partition plate divides the hollow space of the housing into an upstream section and a downstream section. The upstream and downstream sections communicate with each other. The air blower conveys air from the upstream section to the downstream section. The dampers open and close the openings of inlets A and B, and outlets A and B. The controller controls air blowing of the air blower and opening and closing of each damper. Inlets A and B are disposed in the upstream section. Outlets A and B are disposed in the downstream section.

Abstract: Various embodiments are described herein for an environmental control system. In one example embodiment, the system is an HVAC system including an HRV or ERV unit, a first distribution system, and an ambient energy distribution system. The first distribution system has a first end in thermal communication with the HRV or ERV unit and a second end in thermal communication with the interior of a domicile. The ambient energy distribution system extends between first and second locations in the domicile and is isolated from fluid flow communication with the first distribution system. The ambient energy distribution system transfers heat between the first and second locations.

Abstract: The present invention provides a sensor combining a dust sensor and a gas sensor, comprising a light emitting unit for emitting light, a first light receiving unit for receiving scattered light which is emitted by the light emitting unit and scattered by dust to detect dust concentration, a mirror for changing a path of the emitted light which the light emitting unit emits, and a second light receiving unit for receiving the emitted light the path of which is changed by the mirror to detect gas concentration. An inflow section for introducing air into a detection space inside the sensor is formed in a Y-shaped tube in which a first inlet and a second inlet meet. The inflow section comprises a switch which selects a path through which air flows into the detection space out of the first inlet and the second inlet.

Abstract: Certain aspects of the present disclosure relate to a system including a first active control device, comprising: a flow control element; one or more sensors; a network interface configured to connect to a mesh network; a memory comprising computer-executable instructions; and a processor configured to: execute the computer-executable instructions; receive local sensor data from the one or more sensors; receive remote sensor data from a remote sensing device; control a position of the flow control element based on one or more of the local sensor data or the remote sensor data; store the local sensor data and remote sensor data in the memory; and transmit the local sensor data and the remote sensor data to a second active control device via the mesh network.

Abstract: A ventilation grille has an annular shape, and includes a panel and a lamp unit. The panel includes an intake opening provided around a central part of the annular shape, and a frame provided around the intake opening. The lamp unit is provided in the central part of the annular shape. The panel has a structure for attaching and detaching the lamp unit.

Abstract: In order to carry out, in a heating operation, an airflow rate adjusting operation in which a reduced amount of conditioned air is blown in one or more of a plurality of blowing directions to increase a blowing speed in the rest of the blowing directions, an operation control section is configured to control the flow of the conditioned air such that the conditioned air is blown out in a horizontal blow mode in the blowing direction in which the blowing speed is increased by the airflow rate adjusting operation, and periodically change the blowing direction in which a reduced amount of the conditioned air is blown. As a result, temperature variations in the air-conditioning target space in the heating operation are reduced.

Abstract: According to certain embodiments, a controller is operable to instruct a climate control system to operate according to an occupied mode or an unoccupied mode based on a pre-defined schedule. The occupied mode uses pre-defined settings associated with an occupied status, and the unoccupied mode uses pre-defined settings associated with an unoccupied status. The controller is operable to receive an indication that an occupancy sensor detects a space as being occupied. In response to receiving the indication when the pre-defined schedule requires the climate control system to operate in the unoccupied mode, the controller is operable to instruct the climate control system to use the pre-defined settings associated with the occupied status during an override time period.

Abstract: An indoor unit for an air-conditioning apparatus includes a casing, an up-down airflow direction plate rotatably supported in the air outlet, and an auxiliary airflow direction plate rotatably supported below, and on an upstream side of, the up-down airflow direction plate. The up-down airflow direction plate has a main blade part formed of a flat plate and a rear edge part formed of a flat plate. When the main blade part is in a horizontal state, the rear edge part is inclined upward to a back face of the casing from the main blade part. When an angle ? formed between the main blade part and the rear edge part and an angle ? formed between the main blade part and a virtual line through a center of a tip part of the auxiliary airflow direction plate, ? is greater than ?.

Abstract: A Fault Detection Diagnostic (FDD) variable differential and variable fan-off delay Heating Ventilating Air Conditioning (HVAC) thermostat control method. The FDD method detects a fan-on setting, reports a FDD fan-on alarm, overrides a fan-on setting, and turns off an HVAC fan. The FDD method detects, reports, and corrects a short-cycle by providing a variable differential based on: a cooling or heating cycle duration, or an off-cycle time. The variable fan-off delay is based on: a Conditioned Space Temperature (CST), comparing a current CST to the CST measured during the fan-off delay, a rate of change of CST with respect to time (dT/dt), dT/dt reaches an inflection point, the CST crosses a fan-off-delay differential, a cooling cycle duration, a heating cycle duration, a cooling temperature split, a heating temperature rise, an outdoor air temperature, a supply air temperature, or the rate of change with respect to time of these HVAC parameters.

Abstract: A system and method of determining duct leakage in an HVAC system including an HVAC unit assembly operably coupled to a system controller, the method including operating the system controller to determine system leakage data, operating the system controller to determine supply leakage data, and operating the system controller to determine a duct leakage measurement based in part on the system leakage data and the supply leakage data.

Abstract: A controller includes a processor and memory. The memory stores instructions that, when executed, are configured to cause the processor to receive measurements pertaining to a measured operation parameter of at least a portion of a turbine system. The instructions are also configured to cause the processor to generate a customized model for the at least the portion of the turbine system. Moreover, the instructions are configured to cause the processor to estimate an estimated value using the received measurements. The estimated value pertains to a parameter of the turbine system. Furthermore, the instructions are configured to cause the processor to using the customized model, reduce or remove at least some environmental conditions from a corrected estimated value derived from the estimated value.

Abstract: Monitoring airflows through fan arrays and adjusting fan speeds during air handling system operations to dynamically provide and/or maintain balanced discharge airflows. An air handling system controller utilizes fan speed and airflow data values of each fan array to determine whether a fan speed setpoint of the fans of a fan array should be increased or decreased in order to balance the airflow through each fan array. When an increase or decrease in the fan speed setpoint is required, the controller adjusts the fan speeds accordingly.

Abstract: A refrigeration cycle apparatus includes a refrigeration cycle through which refrigerant is circulated, an indoor unit that accommodates at least a load-side heat exchanger of the refrigeration cycle and is placed indoors, and a controller that controls the indoor unit. The indoor unit includes an indoor air-blowing fan, an air inlet through which indoor air is sucked in, and an air outlet through which the air sucked in from the air inlet is blown indoors. The controller activates the indoor air-blowing fan when leakage of refrigerant is detected. An air passage that allows air to pass through the air outlet is established in the air outlet at least when leakage of refrigerant is detected.

Abstract: A building loses or gains heat through its envelope based on the differential between the indoor and outdoor temperatures. The losses or gains are due to conduction and infiltration. Conventionally, these effects are typically estimated by performing an on-site energy audit. However, total thermal conductivity, conduction, and infiltration can be determined empirically. The number of air changes per hour are empirically measured using a CO2 concentration monitoring device, which enables the infiltration component of total thermal conductivity to be measured directly. The conduction component of thermal conductivity can then be determined by subtracting the infiltration component from the building's total thermal conductivity.

Abstract: For controlling the flow of air into the zones (Z1, Z2, Z3, Zi) of a variable air volume HVAC system (1) having actuator driven dampers (D1, D2, D3, Di), which operate in a range from a minimum damper position to a maximum damper position for adjusting the flow of air into a zone (Z1, Z2, Z3, Zi), flow measurement values and current damper positions are transmitted via a telecommunications network (2) to a cloud-based HVAC control center (3). Using the flow measurement values and calibration values, which indicate HVAC system parameters at a defined calibration pressure in the HVAC system (1) and at different damper positions, the cloud-based HVAC control center (3) calculates the minimum damper position for the actuators (A1, A2, A3, Ai), such that the pressure in the HVAC system (1) does not exceed a defined maximum pressure threshold, and transmits the minimum damper position to the actuators.

Abstract: A system for controlling an environment within a fuel tank is provided. The system includes a conduit with a plurality of vents, wherein the conduit defines a path through the fuel tank, and wherein the conduit is configured to direct a flow of air along the path and out the plurality of vents.

Abstract: A system and method for monitoring sensors via surveillance cameras is disclosed. In the system, surveillance cameras generating image data of scenes, where the sensors are included in the scenes. The sensors detect information concerning the scenes and encode the information so that it can be derived from the image data. Preferably, the sensors encode the information concerning the scenes by modulating a visible light source, the signals of which are captured within the image data by the cameras. An analytics system then analyzes the image data and decodes the information from the sensors encoded within the image data. Preferably, an integrated analytics system of the cameras executes the analysis. Exemplary sensors include sensors for detecting temperature, moisture, audio/voice, and product selection in a retail premises.

Abstract: An active side vent system for a vehicle can include a housing disposed in a side vent opening defined by a recessed surface in a rear portion of a front fender of the vehicle, a set of louvers disposed in the housing and configured to pivot such that (i) in an open position, none of the set of louvers extends beyond an outer surface of the front fender and (ii) in a closed position, the set of louvers are substantially flush with the recessed surface of the front fender, and an actuator configured to control the pivoting of the set of louvers.

Abstract: An indoor unit and an air conditioner configured so that each outlet and each flap can be easily identified. An indoor unit (1) is provided with outlets (32a-32d) which discharge air-conditioning air toward the interior space, and also with flaps (35a-35d) having substantially the same shape, the flaps (35a-35d) being respectively disposed at the outlets (32a-32d) and capable of individually changing the discharge directions of the air-conditioning air. Sign sections (60a-60d) which are different from each other are formed either in the vicinities, respectively, of the outlets (32a-32d) or on the flaps (35a-35d), respectively.

Abstract: Disclosed herein is a hybrid ventilation apparatus capable of both natural and forced ventilation. In the case of a natural ventilation mode, a worm gear is rotated in a normal direction by drive force of a drive unit under control of a control unit so that a pressing member engages with a rotation guide protrusion and rotates a damper, thus opening a flow passage, and then the worm gear is reversely rotated by drive force of the drive unit to return the pressing member to its original position, thus allowing a user to rotate a roller upwards and downwards and rotate the damper so that the degree of opening of the flow passage can be adjusted. Thereby, rapid inflow of outdoor air can be blocked, and a cold graft phenomenon, in which the temperature of indoor air rapidly drops, can be prevented.

Abstract: In a demand control ventilation (DCV) system, ID codes of tags worn by occupants are detected in each room by a tag detector and wirelessly communicated to a zonal occupancy compiler. The zonal occupancy count arrived at by the compiler is transmitted to a DCV microprocessor, which interfaces with the ventilation controller of the building's HVAC system and sets the zonal ventilation rate based on the occupancy count and applicable ASHRAE standards.

Abstract: A method for diagnosing a single flow or dual flow ventilation unit, the method making it possible to diagnose the permeability and installation of each conduit of the ventilation unit by means of measuring devices and a control unit.

Abstract: A controller configured so that pieces of information relating to each outlet and each flap which are currently set can be collectively visible on the controller. A controller for an indoor unit provided with flaps having substantially the same shape, the flap being respectively disposed at the outlets and capable of individually changing the discharge directions of air-conditioning air. The controller is provided with a display section for simultaneously displaying information relating to an outlet selected out of the outlets and/or information relating to a flap selected out of the flaps.

Abstract: An apparatus for controlling an opening hole and an electronic equipment having the apparatus for controlling an opening hole. The apparatus is used for the electronic equipment, a case of the electronic equipment is provided with meshes penetrating the case, wherein the apparatus comprises: movable block sheets; a drive mechanism, configured to control the block sheets to switch between a first state blocking the meshes and a second state exposing the meshes. By the setting of the movable block sheets, the apparatus has the first state blocking the meshes of the electronic equipment and the second state exposing the meshes, when the electronic equipment is in use, the blocking sheets may be in the second state to ensure the electronic equipment to operate normally; when it is not in use, the blocking sheets may be in the first state to prevent the foreign matter from invading the electronic equipment.

Abstract: An approach is provided in which a cooling manager retrieves pre-characterization data corresponding to a fan that electronic components included in a computer system. The pre-characterization data includes operational zones based upon fan power measurements and fan speed settings. The cooling manager sets the fan to a first speed setting within a first operational zone, and detects that one of the components generates a temperature change value that exceeds a specified temperature change value corresponding to the component. In turn, the cooling manager selects a second operational zone and sets the fan to a second speed setting within the second operational zone.

Abstract: A computer device and a method for dissipating heat from a discrete graphics processing unit therein are provided. The method thereof includes determining whether the discrete graphics processing is in an operating state. If the discrete graphics processing unit is in an operating state, a determination is made as to whether a current temperature of the discrete graphics processing unit can be obtained. If the current temperature of the discrete graphics processing unit cannot be obtained, the discrete graphics processing unit is cooled so as to lower the current temperature thereof.

Abstract: The invention relates to a control device for room air managing systems, comprising at least one or more rooms (32, 34) or room zones; an inlet air channel (22) and room inlet air channels (22a) branching therefrom; an exhaust air channel (20) and room exhaust air channels (20 a) branching therefrom; an inlet ventilator (16) in the inlet air channel (22); controllable inlet air throttle flaps (14) for the inlet air flow in the room inlet air channel (20a); and, controllable exhaust air throttle flaps (12) for the exhaust air flow in the room exhaust air channel (22a). According to the invention, there is provided a pressure sensor (38) that detects the room pressure in the room (32, 34) that is to be air conditioned, wherein the room pressure constitutes the direct control parameter for the opening position of the inlet air throttle flap (14) and/or the exhaust air throttle flap (12).

Abstract: An air conditioner includes an indoor fan motor driven according to a signal to control the indoor fan motor by a controller, and a controller that resets a reference value of a rated air flow rate according to the pre-set conditions by checking an indoor fan motor driving voltage when an indoor fan motor RPM reaches a reference value of a strong wind mode while the air conditioner operates in strong wind mode. The controller compares the checked indoor fan motor driving voltage with a reference indoor fan motor driving voltage of the rated air flow rate, and resets the reference value when the checked indoor fan motor driving voltage is different from the reference indoor fan motor driving voltage of the rated air flow rate.

Abstract: In the air conditioner, determination is made whether or not a “3-Dimensional Swing” or a “Left/Right Swing” relating to movement of a left/right flap is set (step S2). When it is determined that the “3-Dimensional Swing” or “Left/Right Swing” is set (step S2: Yes), a determination is made whether or not the swing range of the left/right flap is set to a part of the movable range (step S3). When it is determined in step S3 that the swing range of the left/right flap is set (step S3: Yes), the left/right flap is once returned to the reference position (step S4), and then reciprocation of the left/right flap within the swing range is started (step S5).

Abstract: In an exemplary embodiment, an Environmental Optimization System (“EOS”) provides a system for the intelligent control and monitoring of a poultry or livestock house environment through the utilization of a solar thermal collection system, a variety of environmental and livestock behavior sensors, apparatus for controlling the thermal collection and existing interior heating/air conditioning/ventilation (“HVAC”) systems, and Internet or cloud based intelligent control and monitoring capabilities of the system. In various embodiments central sensor data aggregation is utilized to provide improved optimization control for individual structures based on data from multiple structures.

Abstract: Indoor air quality can be improved by monitoring, with at least one air quality sensor, at least one air quality factor of a target environment. Then, based on the collected air quality factor, a HVAC system or an air purification system can be adjusted in order to more efficiently maintain the indoor air quality. Systems that may be used to improve indoor air quality can contain a photo-catalytic oxidation-based air purification system and can communicate with at least one air quality sensor, other purification systems, HVAC system controllers, or a computer configured to monitor and control the air purification systems and HVAC systems.

Abstract: An auxiliary device is tended and adapted to be accommodated in an air conduit forming part of an air conditioning device, to which air conduit first flow components, such as a fan, are connected for the purpose of bringing about a main airflow through the air conduit such that the whole main airflow flows through the auxiliary device. The auxiliary device has an arrangement of a number of air conditioning modules which in an active state of the relevant air conditioning module, each allow passage of a partial flow of the airflow and together allow passage of the whole main flow. Control components adjust each of the air conditioning modules between an active state, in which passage of the relevant partial flow is allowed, and a passive state in which a partial flow substantially amounts to zero or flows in opposite direction.

Abstract: A ventilation system for a building in some cases includes a main HVAC blower for moving temperature-conditioned air through the building plus a smaller ventilation blower for providing fresh air. A controller regulates the ventilation blower's speed to provide a target ventilation flow rate regardless of changes in the pressure differential between the indoor and outdoor air. To ensure that the target rate is appropriate for a particular building, the target flow rate is determined based on a ventilation setting that reflects a specified number of bedrooms and a specified amount of floor space of the building.

Abstract: An air-conditioning indoor unit causes a flow of air blown out from a blow-out port to be diverted in a predetermined direction due to the Coand{hacek over (a)} effect. The air-conditioning indoor unit includes an airflow direction adjustment vane varying a blowout angle of blown air relative to a horizontal plane, a Coand{hacek over (a)} vane turning the blown air into a Coand{hacek over (a)} airflow along a bottom surface, and a control unit. The Coand{hacek over (a)} vane is provided in proximity to the blow-out port. The control unit executes an airflow direction automatic switching mode automatically switching between a Coand{hacek over (a)} effect use state in which the blown air is turned into a Coand{hacek over (a)} airflow along a predetermined surface and diverted in the predetermined direction, and a normal state in which the Coand{hacek over (a)} airflow is not created.

Abstract: A louver system for controlling airflow in a duct from a forced air heating, ventilation, and air conditioning (HVAC) system with a housing and a louver located on a mounting fascia. The system having a longitudinal slat located in the perimeter wall that is movable between the fully open position and the fully closed position via a slat positioning assembly. The slat positioning assembly is powered by a mainspring assembly. A winding assembly is operatively coupled to the mainspring assembly which is wound by a motor or a hand crank. A local control system having a microprocessor, a transmitter, and a receiver sends a positioning signal to the slat positioning assembly that rotates the slat to a specified position via power from the mainspring assembly.

Abstract: Various devices, systems, and methods may be presented. A sensor unit may be presented that includes a housing and a chamber arranged within the housing and configured to receive air from outside of the housing of the sensor unit. Also present may be a sensor arranged within the housing and configured to measure a characteristic within the chamber. The sensor unit may include a fan arranged within the housing in relation to the chamber, the fan configured to clear air from the chamber of the sensor unit. Further, the sensor unit may include a controller in communication with the fan and the sensor, the controller configured to operate the fan.

Abstract: A system is provided for determining whether a damper controlling the flow of make-up air into a kitchen is properly functioning when the kitchen ventilation system is operating. When the kitchen ventilation system is activated, a notification can be provided to a user of the kitchen whereby the user will know whether the damper is open such that make-up air is available for replacing air drawn out of the kitchen by the ventilation system. The notification device can be conveniently positioned in the kitchen so that the user can readily check for proper damper operation when the ventilation system is operating.

Abstract: An energy-reducing method and apparatus for retrofitting a constant volume HVAC system, with or without an economizer, that provides heating, cooling, and ventilation to occupants within a building space. The present invention includes the introduction of a programmable logic controller and variable frequency drive (VFD) that takes control of the existing fan, heating, cooling, and optional economizer operation. The controller is programmed fault detection of fan fault, heat/cool (temperature-based) fault, and energy consumption fault. The reduction of the fan speed in the ventilation mode when the 100% operation is not needed saves significant energy of the existing constant volume HVAC system where the fan motor is designed to run 100% of the time.

Abstract: A ventilation fan includes a body unit, which has a fan disposed in a body case and a fan controller operable to control an air volume of the fan. The ventilation fan also includes a sensor module having an indoor environment detecting sensor and a module controller operable to control a detecting operation of the indoor environment detecting sensor. The body unit has a module mount on which the sensor module is mounted and another sensor module can be mounted in place of the sensor module. The module mount is connected to the fan controller. The module controller outputs detection information obtained based on a detection result of the indoor environment detecting sensor to the fan controller, which in turn controls the air volume of the fan based on the detection information inputted thereto.

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.