Abstract: A problem to be solved by the present disclosure is to realize a fan unit capable of determining occurrence or non-occurrence of a backflow during operation. In a second unit, a second controller calculates front-rear differential pressure by substituting a rotation speed and a volume of air or a wind speed that can be acquired in real time into a relational expression. The relational expression derives, from two values of the rotation speed, the volume of air or the wind speed, and the front-rear differential pressure, the remaining one value. Then, the second controller determines that a backflow occurs if the calculated front-rear differential pressure is within a range that cannot occur under a normal condition. Therefore, the occurrence of a backflow can be detected without using an expensive pressure sensor or a directional wind speed sensor.

Abstract: A problem to be solved by the present disclosure is to realize a fan unit capable of determining occurrence or non-occurrence of a backflow during operation. In a second unit, a second controller calculates front-rear differential pressure by substituting a rotation speed and a volume of air or a wind speed that can be acquired in real time into a relational expression. The relational expression derives, from two values of the rotation speed, the volume of air or the wind speed, and the front-rear differential pressure, the remaining one value. Then, the second controller determines that a backflow occurs if the calculated front-rear differential pressure is within a range that cannot occur under a normal condition. Therefore, the occurrence of a backflow can be detected without using an expensive pressure sensor or a directional wind speed sensor.

Abstract: An air conditioning system configured to supply a plurality of places in a building with conditioned air with use of ducts inhibits malfunction of the air conditioning system due to airflow volume through a utilization heat exchanger. A heat exchanger unit includes a utilization heat exchanger. The heat exchanger unit is connected with a plurality of ducts. A plurality of fan units sucks conditioned air from the heat exchanger unit through the plurality of ducts and supplies a plurality of blow-out ports with the conditioned air. The fan units include fan motors as a plurality of actuators configured to individually change supply air volume of the conditioned air. A main controller controls the plurality of fan motors such that airflow volume through the utilization heat exchanger satisfies a predetermined condition.

Abstract: A fan unit includes a centrifugal fan, an air flow volume detector, and a main body casing housing the centrifugal fan and the air flow volume detector. The centrifugal fan includes a fan casing and a rotor. The air flow volume detector includes main body, and a probe that detects an air flow volume equivalent quantity equivalent to an air flow volume provided by the centrifugal fan. The fan casing includes a bell mouth defining an air inlet and having a convex surface. A distance from the probe to the surface of the bell mouth is larger than 0 and smaller than one third of a radius of the air inlet. A thermal air velocity sensor detects, as the air flow volume equivalent quantity, an air velocity of air flowing through the air inlet not connected to a duct by measuring an amount of heat dissipated from the probe.

Abstract: A fan unit includes a centrifugal fan, an air flow volume detector, and a main body casing housing the centrifugal fan and the air flow volume detector. The centrifugal fan includes a fan casing and a rotor. The air flow volume detector includes main body, and a probe that detects an air flow volume equivalent quantity equivalent to an air flow volume provided by the centrifugal fan. The fan casing includes a bell mouth defining an air inlet and having a convex surface. A distance from the probe to the surface of the bell mouth is larger than 0 and smaller than one third of a radius of the air inlet. A thermal air velocity sensor detects, as the air flow volume equivalent quantity, an air velocity of air flowing through the air inlet not connected to a duct by measuring an amount of heat dissipated from the probe.

Abstract: A problem to be solved by the present disclosure is to realize a fan unit capable of determining occurrence or non-occurrence of a backflow during operation. In a second unit, a second controller calculates front-rear differential pressure by substituting a rotation speed and a volume of air or a wind speed that can be acquired in real time into a relational expression. The relational expression derives, from two values of the rotation speed, the volume of air or the wind speed, and the front-rear differential pressure, the remaining one value. Then, the second controller determines that a backflow occurs if the calculated front-rear differential pressure is within a range that cannot occur under a normal condition. Therefore, the occurrence of a backflow can be detected without using an expensive pressure sensor or a directional wind speed sensor.

Abstract: A fan unit reduces the number of man-hours for a preliminary test and eliminates the need for a trial run at the time of duct connection are realized. A second controller acquires: a rotation speed of a fan motor of a second fan; a volume of air, a wind speed, or front-rear differential pressure of the second fan; and an air volume target value or a wind speed target value for the second fan, and calculates a rotation speed target value Ny for the fan motor 31b by using a first function: Ny=(Qy/Qx)2×?Px×{m×(Qy/Qx)×Vx+p}+n×(Qy/Qx)×Vx+q. Furthermore, when the front-rear differential pressure fluctuates and the wind speed is decreased from Vt to V, the second controller calculates a rotation speed change amount to the rotation speed target value by using a second function: ?N=a×(Vt?V).

Abstract: A problem to be solved by the present disclosure is to enhance the reliability of determination of occurrence or non-occurrence of surging. Whether or not surging occurs depends on front-rear differential pressure. Therefore, by determining occurrence or non-occurrence of surging on the basis of the front-rear differential pressure, a second unit can detect and avoid surging with higher accuracy than when determining by using the pressure on an outlet side of a second fan.

Abstract: A blow-out unit disposed at a blow-out port on an air flow path and configured to blow out air supplied through the air flow path, toward the room, includes: a first member disposed in the blow-out port and including a plate member having a first side and configured to turn around a rotating shaft disposed away from the first side such that the first side moves away from the blow-out port toward the air flow path; and a second member disposed in the blow-out port at a different position from the plate member and extending along the first side of the plate member. The plate member and the second member change a direction of air to be blown out toward the blow-out port through the air flow path from a first air flow direction to a second air flow direction.

Abstract: Provided is an air conditioning system that uses ducts to supply conditioned air to a plurality of places inside a building, and is configured to counteract air backflow that occurs in ducts. A heat exchanger unit (10) includes a use side heat exchanger (11). A plurality of ducts (20) are connected to the heat exchanger unit (10). A plurality of fan units (30) suction conditioned air from the heat exchanger unit (10), and supply the conditioned air to a plurality of air outlets (71) through the plurality of ducts (20). A differential pressure sensor (121) acting as a detection device detects air backflow proceeding from at least one air outlet (71) among the plurality of air outlets (71) toward the heat exchanger unit (10) in a plurality of distribution flow paths including the plurality of ducts (20), the plurality of fan units (30), and the air outlets (71) of a plurality of outlet units (70).

Abstract: The present disclosure controls the supply of conditioned air to moderate the energy consumption by the heat source side in the supply of conditioned air using ducts in an air conditioning system. A heat exchanger unit includes a use side heat exchanger. A plurality of ducts distribute conditioned air that has passed through the use side heat exchanger of the heat exchanger unit. A plurality of fan units suction the conditioned air from the heat exchanger unit through the plurality of ducts, and supply the conditioned air to an air conditioned space. Each fan unit includes a fan motor that acts as an actuator configured to change an individual air supply amount of the conditioned air. A controller controls the plurality of fan motors to control the respective air supply amounts of the plurality of fan units.

Abstract: A control load is reduced in a fan unit capable of controlling air flow volume. The rotation speed of a fan can be changed. An air flow volume detector detects air flow volume of the fan or equivalent air flow volume that is a physical quantity corresponding to the air flow volume of the fan. A unit casing houses, therein, the fan and the air flow volume detector. A fan controller, which is a controller, controls the rotation speed of the fan. The fan controller controls the rotation speed of the fan on the basis of a command value of the air flow volume of the fan given from outside the unit and a detected value of the air flow volume or the equivalent air flow volume detected by the air flow volume detector.

Abstract: An air conditioning system configured to supply a plurality of places in a building with conditioned air with use of ducts inhibits malfunction of the air conditioning system due to airflow volume through a utilization heat exchanger. A heat exchanger unit includes a utilization heat exchanger. The heat exchanger unit is connected with a plurality of ducts. A plurality of fan units sucks conditioned air from the heat exchanger unit through the plurality of ducts and supplies a plurality of blow-out ports with the conditioned air. The fan units include fan motors as a plurality of actuators configured to individually change supply air volume of the conditioned air. A main controller controls the plurality of fan motors such that airflow volume through the utilization heat exchanger satisfies a predetermined condition.

Abstract: Provided is an air conditioning system that uses ducts to supply conditioned air to a plurality of places inside a building, and is configured to counteract air backflow that occurs in ducts. A heat exchanger unit includes a use side heat exchanger. A plurality of ducts are connected to the heat exchanger unit. A plurality of fan units suction conditioned air from the heat exchanger unit, and supply the conditioned air to a plurality of air outlets through the plurality of ducts. A differential pressure sensor acting as a detector detects air backflow proceeding from at least one air outlet among the plurality of air outlets toward the heat exchanger unit in a plurality of distribution flow paths including the plurality of ducts, the plurality of fan units, and the air outlets of a plurality of outlet units.

Abstract: An air treatment system controls airflow volume in accordance with momentarily varying airflow volume to be demanded. A supply fan unit is disposed separately from an air treatment unit, and sends outdoor air from an outdoor space to the air treatment unit and sends outdoor air treated by the air treatment unit to an indoor space. An exhaust fan unit is disposed separately from the air treatment unit, and sends indoor air from the indoor space to the air treatment unit and sends indoor air treated by the air treatment unit to the outdoor space. A controller controls a rotation speed of a first fan in accordance with a first detection value of a first airflow volume detection unit, and controls a rotation speed of a second fan in accordance with a second detection value of a second airflow volume detection unit.