An air-conditioner with refrigerant-134a as working fluid is used to keep a room at 23°C by rejecting the waste heat to the outdoor air at 34°C. The room gains heat through the walls and the windows at a rate of 250 kJ/min while the heat generated by the computer, TV and lights amounts to 900 W. The refrigerant enters the compressor at 400 kPa as a saturated vapor at a rate of 80 L/min and leaves at 1200 kPa and 70°C. Determine a) the actual COP, b) maximum COP, and c) minimum power input.

An air-conditioner with refrigerant-134a as working fluid is used to keep a room at 23°C by rejecting the waste heat to the outdoor air at 34°C. The room gains heat through the walls and the windows at a rate of 250 kJ/min while the heat generated by the computer, TV and lights amounts to 900 W. The refrigerant enters the compressor at 400 kPa as a saturated vapor at a rate of 80 L/min and leaves at 1200 kPa and 70°C. Determine a) the actual COP, b) maximum COP, and c) minimum power input.

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 12RQ: Refrigerators currently being manufactured in the United States are using______as their refrigerant.

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