Abstract: A heat exchanger is provided with stacked coil sections. Each of the stacked coil sections is configured to circulate a fluid independent from the other coil section. An air moving device is used to circulate air through both of the stacked coil sections. The stacked coil sections are positioned to have the air exiting the one coil section entering the other coil section.

Abstract: A method for controlling an economizer circuit is provided. The economizer circuit includes a valve to regulate refrigerant flow between the economizer and the compressor. The valve can be opened to engage the economizer circuit or closed to disengage the economizer circuit based on the output frequency provided to the compressor motor by a variable speed drive and an operating condition of the economizer.

Abstract: A heat exchanger is provided with stacked coil sections. Each of the stacked coil sections is configured to circulate a fluid independent from the other coil section. An air moving device is used to circulate air through both of the stacked coil sections. The stacked coil sections are positioned to have the air exiting the one coil section entering the other coil section.

Abstract: A heat exchanger is provided with stacked coil sections. Each of the stacked coil sections is configured to circulate a fluid independent from the other coil section. An air moving device is used to circulate air through both of the stacked coil sections. The stacked coil sections are positioned to have the air exiting the one coil section entering the other coil section.

Abstract: A method for controlling an economizer circuit is provided. The economizer circuit includes a valve to regulate refrigerant flow between the economizer and the compressor. The valve can be opened to engage the economizer circuit or closed to disengage the economizer circuit based on the output frequency provided to the compressor motor by a variable speed drive and an operating condition of the economizer.

Abstract: A system and method for controlling an economizer circuit is provided. The economizer circuit includes a valve to regulate refrigerant flow between the economizer and the compressor. The valve can be opened to engage the economizer circuit or closed to disengage the economizer circuit based on the output frequency provided to the compressor motor by a variable speed drive and an operating condition of the economizer.

Abstract: A system and method for controlling an economizer circuit is provided. The economizer circuit includes a valve to regulate refrigerant flow between the economizer and the compressor. The valve can be opened to engage the economizer circuit or closed to disengage the economizer circuit based on the output frequency provided to the compressor motor by a variable speed drive and an operating condition of the economizer.

Abstract: A heating, ventilation, air conditioning and refrigeration (HVAC&R) system having a compressor, a heat exchanger, an expansion valve, and a multichannel heat exchanger connected in a closed refrigerant loop. The multichannel heat exchanger has at least two fluid flow paths cooled by a flow of air from an air-moving device through the multichannel heat exchanger. Each of the at least two fluid flow paths have an inlet and an outlet in communication there between. The multichannel heat exchanger also has at least one flow regulator disposed in at least one outlet to regulate through at least one fluid flow path in response to the air flow through the heat exchanger to achieve a substantially equal temperature of a fluid flowing in the at least two flow paths.

Abstract: A heat exchanger is provided with stacked coil sections. Each of the stacked coil sections is configured to circulate a fluid independent from the other coil section. An air moving device is used to circulate air through both of the stacked coil sections. The stacked coil sections are positioned to have the air exiting the one coil section entering the other coil section.

Abstract: A vapor compression system that circulates a fluid through a closed loop interconnecting a compressor, a first heat exchanger, a flow-restricting expansion device, and a second heat exchanger. The system further includes a vessel in a first fluid communication and a selective second fluid communication with the loop between the compressor and the first heat exchanger with each of the first and second fluid communication configured to receive fluid from the loop. The vessel is in a third fluid communication with the first heat exchanger configured to provide fluid to the first heat exchanger. In response to a predetermined ambient temperature surrounding the system, the second fluid communication is selectively opened to provide an increased fluid flow from the vessel to the first heat exchanger.

Abstract: A control algorithm for controlling an economizer circuit in a chiller system is provided. The control algorithm opens and closes a port valve in the economizer circuit in response to predetermined criteria to engage and disengage the economizer circuit. The predetermined criteria can include an operating parameter of a compressor and a level of liquid refrigerant in a flash tank.

Abstract: A heating, ventilation, air conditioning and refrigeration (HVAC&R) system having a compressor, a heat exchanger, an expansion valve, and a multichannel heat exchanger connected in a closed refrigerant loop. The multichannel heat exchanger has at least two fluid flow paths cooled by a flow of air from an air-moving device through the multichannel heat exchanger. Each of the at least two fluid flow paths have an inlet and an outlet in communication there between. The multichannel heat exchanger also has at least one flow regulator disposed in at least one outlet to regulate through at least one fluid flow path in response to the air flow through the heat exchanger to achieve a substantially equal temperature of a fluid flowing in the at least two flow paths.

Abstract: A control algorithm for controlling an economizer circuit in a chiller system is provided. The control algorithm opens and closes a port valve in the economizer circuit in response to predetermined criteria to engage and disengage the economizer circuit. The predetermined criteria can include an operating parameter of a compressor and a level of liquid refrigerant in a flash tank.

Abstract: A flow regulator being disposed in at least one of the outlets of a condenser to regulate the fluid flow in the condenser. The condenser has at least two fluid flow paths and an air flow drawn through the condenser by a condenser fan. The flow regulator regulates the fluid flow to substantially equalize the temperature of the fluid flow in the at least two fluid paths and to provide more efficient cooling of the fluid in the fluid flow paths.

Abstract: A control algorithm for controlling an economizer circuit in a chiller system is provided. The control algorithm opens and closes a port valve in the economizer circuit in response to predetermined criteria to engage and disengage the economizer circuit. The predetermined criteria can include an operating parameter of a compressor and a level of liquid refrigerant in a flash tank.