Abstract: A manifold assembly includes a first channel, a second channel and a manifold. The first channel has a first flow profile and a manifold end with a first cross-sectional geometry. The second channel has a second flow profile and a manifold end with a second cross-sectional geometry, which may be different than the first cross-sectional geometry. A first channel port of the manifold is configured to mate with the manifold end of the first channel. A second channel port of the manifold is configured to mate with the manifold end of the second channel.

Abstract: A manifold assembly for distributing a fluid to a heat exchanger, and a method for producing the same, is provided. The manifold assembly includes a plurality of channels and a manifold. The plurality of channels includes one or more first channels and one or more second channels. The first channels each have a first flow profile and a manifold end with a first cross-sectional geometry. The second channels each have a second flow profile and a manifold end with a second cross-sectional geometry. The first cross-sectional geometry is different from the second cross-sectional geometry. The manifold has an inner cavity, an inlet port, one or more first channel ports, and one or more second channel ports. The first channel ports are each configured to mate with the manifold end of a first channel. The second channel ports are each configured to mate with the manifold end of a second channel.

Abstract: An economizer, and a method for operating the same, is provided having a housing with external airflow section and an internal airflow section. The external airflow section includes one or more external flow blades mounted in an external airflow path. The external flow blades are selectively rotatable between an open position and a substantially closed position. The internal airflow section includes one or more internal flow blades mounted in an internal airflow path. The internal flow blades are selectively rotatable between an open position and a substantially closed position. Each internal flow blade includes a leading portion. The leading portion of each internal flow blade is substantially parallel to the internal airflow path when the internal flow blades are disposed in the open position.

Abstract: A method and system for staging the cooling effect of an air conditioning unit in which outside air is substantially prevented from passing through the cooling unit for a prescribed time after the cooling function has been initiated.

Abstract: A method and system for staging the cooling effect of an air conditioning unit in which outside air is substantially prevented from passing through the cooling unit for a prescribed time after the cooling function has been initiated.

Abstract: The present invention is a pretrip routine for testing a refrigeration system comprising a series of tests for testing aspects of mechanical operation of various individual components of the refrigeration system. In a preferred embodiment, a control unit executes the method of the invention by first testing mechanical operation of a refrigeration system compressor, then tests for leaks in high-to-low-side valves of a refrigeration system, before testing for leaks in a discharge test valve. A control unit may also test the opening/closing operation of various refrigeration system valves before, intermediate or subsequent to executing the above tests. The pretrip routine of the invention validates operation of a refrigeration system as a whole by testing the mechanical operation of individual system component, and, in testing the operation of those various system components, readily isolates the source of a particular problem within a particular component of a refrigeration system.

Abstract: A method for the automated detection of leaks between the high and low-pressure sides of a refrigeration system is provided. A large pressure difference is created between the high pressure side and low-pressure side. By measuring and comparing system pressures at different times, the operational condition of valves which connect the high pressure side to the low-pressure side is accurately determined. By accurately determining that these valves are operating correctly, and in particular that no leaks exist in the valves, reports of false failures are prevented, while the reduction in the refrigeration system's capacity to heat or cool is prevented.

Abstract: A refrigeration/heating system for cooling or heating an area includes a condenser for removing heat from the system to an external environment, an evaporator for receiving heat from the area to be cooled or delivering heat to the area to be heated, and a compressor for raising the pressure and the temperature of a refrigerant. The compressor has at least one cylinder bank and an unloader connected to the cylinder bank for loading and unloading the cylinder bank. Pressure transducers measure the suction and discharge pressures of the compressor when the state of a cylinder bank is changed from a loaded to an unloaded state. A processor uses the suction and discharge pressures in the various states to determine the operational condition of either unloader. By varying the loading and unloading of a pair of cylinder banks, the processor can also use various suction and discharge pressures to determine if a problem exists within either cylinder bank or unloader.

Abstract: A method is provided for controlling a pressure in a refrigeration system which maintains a pressure within a refrigeration system below a predetermined upper limit, may optionally maintain the pressure above a predetermined lower limit. The pressure being controlled can be a discharge pressure, a suction pressure or the difference therebetween.

Abstract: A method is provided for determining whether leaks are present in a discharge check valve of a refrigeration system. The method includes steps of establishing a pressure difference between a high pressure side and a low pressure side of the refrigeration system, temporarily stopping compression of a refrigerant, allowing the refrigerant to flow to the low-pressure sides, and then determining the discharge pressure changes with time.

Abstract: A refrigeration system for cooling or heating an area includes a condenser for removing heat from the system to an external environment, an evaporator for receiving heat from the area to be cooled or delivering heat to the area to be heated, and a compressor for raising the pressure and the temperature of a refrigerant. Prior to placing the system in a cooling or heating/defrost mode, it is desirable to run a pretrip routine to determine the operational condition of the refrigeration system. In the present invention, a pretrip device determines a refrigeration system parameter, and from this parameter selects one of at least two possible pretrip routine variations. Finally, the pretrip device executes the selected pretrip routine in order to determine the operational condition of a refrigeration system.