The catalogue for a refrigerant 22, four-cylinder, hermetic compressor operating at 29 r/s. a condensing temperature of 40 °C and an evaporating temperature of -4 °C shows a refrigeration capacity of 96.4 kW. At this operating points the motor (whose efficiency is 90 percent) draws 28.9 kW. The bore of the cylinders is 87 mm and the piston stroke is 70 mm. The performance data are based on 8 °C of subcooling of the liquid leaving the condenser. Compute 3.1 the actual volumetric efficiency and 3.2 the compression efficiency.

The catalogue for a refrigerant 22, four-cylinder, hermetic compressor operating at 29 r/s. a condensing temperature of 40 °C and an evaporating temperature of -4 °C shows a refrigeration capacity of 96.4 kW. At this operating points the motor (whose efficiency is 90 percent) draws 28.9 kW. The bore of the cylinders is 87 mm and the piston stroke is 70 mm. The performance data are based on 8 °C of subcooling of the liquid leaving the condenser. Compute 3.1 the actual volumetric efficiency and 3.2 the compression efficiency.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter40: Typical Operating Conditions

Section: Chapter Questions

Problem 14RQ: The compressor amperage of a 3-ton system operating on 230 V is approximately -A.

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