A geothermal heat pump running a simple heat pump cycle uses R-134a as the refrigerant and sources thermal energy from well water. The well water enters the evaporator at 13°C and exits at 7°C, with negligible pressure drop. On the refrigerant side, the evaporator operates isobarically at 320 kPa and the refrigerant exits the evaporator at 10°C. The refrigerant is compressed to 1200 kPa through the compressor, which has an isentropic efficiency of 90%. In the condenser, air absorbs energy from the refrigerant at a rate of 4.5 tons (1 ton = 211 kJ/min) as its temperature increases from 22°C at the condenser inlet to 42°C at the condenser outlet. The condenser operates isobarically, and the refrigerant exits the condenser at 20°C. Calculate the input power to the compressor and the COP of the heat pump.

A geothermal heat pump running a simple heat pump cycle uses R-134a as the refrigerant and sources thermal energy from well water. The well water enters the evaporator at 13°C and exits at 7°C, with negligible pressure drop. On the refrigerant side, the evaporator operates isobarically at 320 kPa and the refrigerant exits the evaporator at 10°C. The refrigerant is compressed to 1200 kPa through the compressor, which has an isentropic efficiency of 90%. In the condenser, air absorbs energy from the refrigerant at a rate of 4.5 tons (1 ton = 211 kJ/min) as its temperature increases from 22°C at the condenser inlet to 42°C at the condenser outlet. The condenser operates isobarically, and the refrigerant exits the condenser at 20°C. Calculate the input power to the compressor and the COP of the heat pump.

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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