7-104 An air conditioner with refrigerant-134a as the working fluid is used to keep a room at 23°C by reject ing the waste heat to the outdoor air at 34°C. The room gains heat through the walls and the windows at a rate o 250 kJ/min while the heat generated by the computer, TV and lights amounts to 900 W. The refrigerant enters the com pressor at 400 kPa as a saturated vapor at a rate of 80 L/mi and leaves at 1200 kPa and 70°C. Determine (a) the actua COP, (b) the maximum COP, and (c) the minimum volum flow rate of the refrigerant at the compressor inlet for the same compressor inlet and exit conditions. Answers: (a) 4.33 (b) 26.9, (c) 12.9 L/min QH

7-104 An air conditioner with refrigerant-134a as the working fluid is used to keep a room at 23°C by reject ing the waste heat to the outdoor air at 34°C. The room gains heat through the walls and the windows at a rate o 250 kJ/min while the heat generated by the computer, TV and lights amounts to 900 W. The refrigerant enters the com pressor at 400 kPa as a saturated vapor at a rate of 80 L/mi and leaves at 1200 kPa and 70°C. Determine (a) the actua COP, (b) the maximum COP, and (c) the minimum volum flow rate of the refrigerant at the compressor inlet for the same compressor inlet and exit conditions. Answers: (a) 4.33 (b) 26.9, (c) 12.9 L/min QH

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

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 2RQ: The operating condition for the single compressor in a household refrigerator is the lowest box...

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