Abstract: A condenser for a vapor compression system includes a shell, a tube bundle, and a tube support structure. The shell has a refrigerant inlet and a refrigerant outlet. The tube bundle includes a plurality of heat transfer tubes disposed inside the shell. Refrigerant discharged from the refrigerant inlet is supplied onto the tube bundle. The heat transfer tubes extend generally parallel to the longitudinal center axis of the shell. The tube support structure is configured and arranged to support the plurality of heat transfer tubes in the tube bundle within the shell. The tube support structure includes at least one tube support plate inclined relative to a vertical direction perpendicular to the longitudinal center axis of the shell.

Abstract: A centrifugal compressor for a chiller includes a casing, an inlet guide vane, an impeller downstream of the inlet guide vane, a motor and a diffuser. The casing has inlet and outlet portions with the inlet guide vane disposed in the inlet portion. The impeller is rotatable about a rotation axis defining an axial direction, and the impeller is adjustably mounted within the casing along the axial direction between at least a first flow rate position and a second flow rate position. The motor rotates the impeller. The diffuser is disposed in the outlet portion downstream from the impeller with a outlet port of the outlet portion being disposed between the impeller and the diffuser.

Abstract: A centrifugal compressor for a chiller includes a casing, an inlet guide vane, an impeller downstream of the inlet guide vane, a rotational magnetic bearing, a magnetic bearing sensor, a motor, a diffuser and a controller. The casing has inlet and outlet portions with the inlet guide vane disposed in the inlet portion. The impeller is attached to a shaft. The radial magnetic bearing rotatably supports the shaft. The magnetic bearing sensor detects at least one of a position signal indicative of the shaft's position and a current signal indicative of current supplied to the magnetic bearing. The motor rotates the shaft in order to rotate the impeller. The diffuser is disposed in the outlet portion downstream from the impeller. An outlet port of the outlet portion is disposed between the impeller and the diffuser. The controller is programmed to predict surge based on the position signal and/or the current signal.

Abstract: A non-condensable gas purge system is configured to be used in a chiller system that uses a low pressure refrigerant in a loop refrigeration circuit. The non-condensable gas purge system includes a purge tank and a purge heat exchanger coil arranged inside the purge tank. The purge tank has a tank inlet for receiving the low pressure refrigerant from a condenser of the refrigeration circuit, a tank outlet for returning the low pressure refrigerant to an evaporator of the refrigeration circuit, and a purge outlet for purging non-condensable gas from the purge tank to the ambient atmosphere. The purge heat exchanger coil is fluidly connected to the loop refrigeration circuit such that the low pressure refrigerant contained in the loop of the chiller system can pass through the purge heat exchanger coil. Refrigerant in the purge tank is condensed by the heat exchanger coil while non-condensable gases remain gaseous.

Abstract: A method of producing refrigeration includes compressing a refrigerant composition including R1233zd in a compressor having a magnetic bearing, within a chiller system.

Abstract: A heat exchanger includes a shell, a refrigerant distributor disposed in the shell, and a heat transferring unit disposed in the shell. The shell has a refrigerant inlet through which at least liquid refrigerant flows and a shell refrigerant vapor outlet. The refrigerant distributor includes a first portion and a second portion. The first portion is connected to the refrigerant inlet to receive refrigerant from the inlet. The first portion has at least one first refrigerant liquid distribution opening and a first refrigerant vapor distribution outlet opening. The second portion is connected to the first portion to receive refrigerant from the first refrigerant liquid distribution opening. The second portion has at least one second refrigerant liquid distribution opening and at least one second refrigerant vapor distribution outlet opening. The heat transferring unit is disposed below the refrigerant distributor to receive liquid refrigerant discharged from the second portion of refrigerant distributor.

Abstract: A centrifugal compressor for a chiller includes a casing, an inlet guide vane, an impeller downstream of the inlet guide vane, a motor and a diffuser. The casing has inlet and outlet portions with the inlet guide vane disposed in the inlet portion. The impeller is rotatable about a rotation axis defining an axial direction. The motor rotates the impeller. The diffuser is disposed in the outlet portion downstream from the impeller with an outlet port of the outlet portion being disposed between the impeller and the diffuser. A hot gas injection passage is provided to inject hot gas refrigerant between the inlet guide vane and the impeller. A controller is programmed to control an amount of the hot gas refrigerant.

Abstract: A centrifugal compressor includes a casing, an inlet guide vane, an impeller, a motor, a diffuser and a cooling medium delivery structure. The motor includes a rotor mounted on the shaft and a stator disposed radially outwardly of the rotor to form a gap between the rotor and the stator. The cooling medium delivery structure includes inlet and outlet conduits located to supply and discharge a cooling medium to and from the motor. The shaft has an external shape different than an internal shape of the rotor to form at least one axial passageway between the shaft and the rotor. The cooling medium is supplied through the gap and the at least one axial passageway to cool the rotor.

Abstract: A refrigerating apparatus includes a centrifugal compressor, a capacity control mechanism that controls a capacity of the compressor by changing an opening degree of the capacity control mechanism, an expansion mechanism that reduces a pressure of a refrigerant, and a controller. The controller calculates an opening degree of the expansion mechanism using compressor capacity as one of a plurality of indices of change in load. The compressor capacity is obtained from a current rotation number of the compressor, an opening degree of the capacity control mechanism, and a divergence rate of a current operation head from a surge region.

Abstract: A heat exchanger for a vapor compression system includes a shell, a distributing part disposed inside of the shell to distribute a refrigerant, a tube bundle and a trough part. The tube bundle includes a plurality of heat transfer tubes disposed inside of the shell below the distributing part. The tube bundle includes a falling film region disposed below the distributing part, an accumulating region disposed below the falling film region, and a flooded region disposed below the accumulating region at a bottom portion of the shell. The trough part extends under at least one of the heat transfer tubes in the accumulating region to accumulate the refrigerant therein. The trough part at least partially overlaps with the at least one of the heat transfer tubes in the accumulating region when viewed along a horizontal direction perpendicular to the longitudinal center axis of the shell.

Abstract: A heat exchanger for a vapor compression system includes a shell with a longitudinal center axis extending generally parallel to a horizontal plane, a distributing part, a tube bundle, a trough part and a guide part. The distributing part distributes a refrigerant. The tube bundle includes a plurality of heat transfer tubes disposed below the distributing part so that the refrigerant discharged from the distributing part is supplied onto the tube bundle. The heat transfer tubes extend generally parallel to the longitudinal center axis of the shell. The trough part extends generally parallel to the longitudinal center axis of the shell under at least one of the heat transfer tubes to accumulate the refrigerant in the trough part. The guide part includes at least one lateral side portion extending upwardly and laterally outwardly from the tube bundle at a vertical position at an upper end of the trough part.

Abstract: A heat exchanger includes a shell, a refrigerant distribution assembly, a heat transferring unit and a canopy member. The refrigerant distribution assembly receives a refrigerant that enters the shell and discharges the refrigerant. The refrigerant distribution assembly has at least one outermost lateral end. The heat transferring unit is disposed below the refrigerant distribution assembly so that the refrigerant discharged from the refrigerant distribution assembly is supplied to the heat transferring unit. The heat transferring unit includes a plurality heat transfer tubes. The canopy member includes at least one lateral side portion extending laterally outwardly and downwardly from a position above the refrigerant distribution assembly. The lateral side portion has a free end disposed laterally further from a vertical plane than the refrigerant distribution assembly, and lower than an upper edge of the outermost lateral end of the refrigerant distribution assembly.

Abstract: A control system for operating the HVAC systems within a building to control the environmental conditions within a building having an onsite component networked to a remote offsite component. The onsite component monitors the conditions within the building and operates the HVAC systems, while the offsite component can be used by the system provider to communicate updates to the onsite component and monitor the effectiveness of the control algorithms used to operate the HVAC systems. The invention includes the method of providing tailored HVAC related controls, reports, notices and diagnostic services to a client under various subscription plans.

Abstract: A heat exchanger is adapted to be used in a vapor compression system, and includes a shell, a distributing part and a tube bundle. The tube bundle includes a plurality of heat transfer tubes arranged in a plurality of columns extending parallel to each other when viewed along the longitudinal center axis of the shell. The heat transfer tubes has at least one of: an arrangement in which a vertical pitch between adjacent ones of the heat transfer tubes in at least one of the columns is larger in an upper region of the tube bundle than in a lower region of the tube bundle; and an arrangement in which a horizontal pitch between adjacent ones of the columns is larger in an outer region of the tube bundle than in an inner region of the tube bundle.

Abstract: A heat exchanger includes a shell, a refrigerant distribution assembly and a heat transferring unit. The refrigerant distribution assembly includes a first tray part and second tray parts. The first tray part continuously extends generally parallel to the longitudinal center axis of the shell to receive a refrigerant that enters the shell. The second tray parts are disposed below the first tray part to receive the refrigerant discharged from first discharge apertures such that the refrigerant accumulated in the second tray parts does not communicate between the second tray parts. The second tray parts are aligned along a direction generally parallel to the longitudinal center axis of the shell. The heat transferring unit is disposed below the second tray parts so that the refrigerant discharged from second discharge apertures of the second tray parts is supplied to the heat transferring unit.

Abstract: A high efficiency, low maintenance single stage or multi-stage centrifugal compressor assembly for large cooling installations. A cooling system provides direct, two-phase cooling of the rotor by combining gas refrigerant from the evaporator section with liquid refrigerant from the condenser section to affect a liquid/vapor refrigerant mixture. Cooling of the stator with liquid refrigerant may be provided by a similar technique. A noise suppression system is provided by injecting liquid refrigerant spray at points between the impeller and the condenser section. The liquid refrigerant may be sourced from high pressure liquid refrigerant from the condenser section.

Abstract: A refrigerating apparatus includes a centrifugal compressor, a capacity control mechanism that controls a capacity of the compressor by changing an opening degree of the capacity control mechanism, an expansion mechanism that reduces a pressure of a refrigerant, and a controller. The controller calculates an opening degree of the expansion mechanism using compressor capacity as one of a plurality of indices of change in load. The compressor capacity is obtained from a current rotation number of the compressor, an opening degree of the capacity control mechanism, and a divergence rate of a current operation head from a surge region.

Abstract: A refrigerating apparatus includes a centrifugal compressor, suction and discharge capacity control mechanisms that control capacity of the compressor by changing opening degrees of the suction and discharge capacity control mechanisms, and a controller that compares a compressor-specific surge curve with an isentropic head to perform rotational speed control of the compressor, rotational speed adjustment control of the compressor in order to avoid surge, and emergency shutdown control of the compressor upon detection of surge. The compressor-specific surge curve is stored in the controller in advance, and is defined by an actual rotational speed of the compressor and opening degrees of the suction and discharge capacity control mechanisms. The isentropic head is calculated based on a suction pressure, a discharge pressure, and a suction temperature during operation.