Abstract: A method of evaluating performance of a chiller is provided. The method includes detecting a plurality of operating parameters of the chiller with a plurality of sensors. The method also includes individually determining a first coefficient of performance degradation due to condenser fouling. The method further includes individually determining a second coefficient of performance degradation due to condenser water flow reduction. The method yet further includes individually determining a third coefficient of performance degradation due to evaporator fouling. The method also includes determining a total coefficient of performance degradation of the chiller with a summation of the first, second and third coefficient of performance degradations.

Abstract: A lubricant separator includes a shell, a vapor inlet located at a first end of the shell to admit a flow of refrigerant and lubricant into the lubricant separator and a muffler positioned in the shell. The muffler includes a first perforated pipe extending along a longitudinal axis of the shell from the vapor inlet, a second perforated pipe radially spaced from the first perforated pipe, an absorption material layer positioned radially outboard of the second perforated pipe, and a lubricant-permeable liner positioned radially between the second perforated pipe and the absorption material layer. The lubricant-permeable liner allows for acoustic wave transmission from the second perforated pipe to the absorption material layer.

Abstract: A lubricant separator includes a shell, a vapor inlet located at a first end of the shell to admit a flow of refrigerant and lubricant into the lubricant separator and a muffler positioned in the shell. The muffler includes a first perforated pipe extending along a longitudinal axis of the shell from the vapor inlet, a second perforated pipe radially spaced from the first perforated pipe, an absorption material layer positioned radially outboard of the second perforated pipe, and a lubricant-permeable liner positioned radially between the second perforated pipe and the absorption material layer. The lubricant-permeable liner allows for acoustic wave transmission from the second perforated pipe to the absorption material layer.

Abstract: A method of evaluating performance of a chiller is provided. The method includes detecting a plurality of operating parameters of the chiller with a plurality of sensors. The method also includes individually determining a first coefficient of performance degradation due to condenser fouling. The method further includes individually determining a second coefficient of performance degradation due to condenser water flow reduction. The method yet further includes individually determining a third coefficient of performance degradation due to evaporator fouling. The method also includes determining a total coefficient of performance degradation of the chiller with a summation of the first, second and third coefficient of performance degradations.

Abstract: An air conditioning system having a cooling mode and a free-cooling mode is provided. The system includes a refrigeration circuit, two pressure sensors, a controller, and a pump-protection sequence resident on the controller. The refrigeration circuit includes a compressor and a pump. The first pressure sensor is at an inlet of the pump, while the second pressure sensor is at an outlet of the pump. The controller selectively operates in the cooling mode by circulating and compressing a refrigerant through the refrigeration circuit via the compressor or operates in the free-cooling mode by circulating the refrigerant through the refrigeration circuit via the pump: The pump-protection sequence turns the pump to an off state based at least upon a differential pressure determined by the controller from pressures detected by the first and second pressure sensors.

Abstract: An air conditioning system having a cooling mode and a free-cooling mode is provided. The system includes a refrigeration circuit, two pressure sensors, a controller, and a pump-protection sequence resident on the controller. The refrigeration circuit includes a compressor and a pump. The first pressure sensor is at an inlet of the pump, while the second pressure sensor is at an outlet of the pump. The controller selectively operates in the cooling mode by circulating and compressing a refrigerant through the refrigeration circuit via the compressor or operates in the free-cooling mode by circulating the refrigerant through the refrigeration circuit via the pump: The pump-protection sequence turns the pump to an off state based at least upon a differential pressure determined by the controller from pressures detected by the first and second pressure sensors.

Abstract: An air conditioning system having a cooling mode and a free-cooling mode. The system includes a refrigeration circuit have a compressor, a pump, an expansion device having a variable opening, and a controller. The controller selectively operates the system in the cooling mode by circulating and compressing a refrigerant through the refrigeration circuit via said compressor, or in the free-cooling mode by circulating the refrigerant through the refrigeration circuit via the pump. A free-cooling limitation and variation sequence resides on said controller and varies the variable opening based at least upon a differential temperature.