The evaporator pressure of the vapor compression heat pump using R-134a as a refrigerant, which you are considering to buy in your home, is 6.45 bar and the condenser pressure is 15.94 bar. The heating requirement of your house in winter is 90 MJ/h and the compressor in the system works with 75% efficiency. The unit price of electricity is 0.9 TL/kWh, and that of natural gas is 0.35 TL/kWh. The efficiency of your existing gas fired combi boiler is 80%. Accordingly, whether the heat pump or your existing combi boiler will heat your house more economically, specify the reason. Also draw the T-S diagram for the heat pump. Indicate the locations of the compressor, condenser and evaporator with the points on the diagram.

The evaporator pressure of the vapor compression heat pump using R-134a as a refrigerant, which you are considering to buy in your home, is 6.45 bar and the condenser pressure is 15.94 bar. The heating requirement of your house in winter is 90 MJ/h and the compressor in the system works with 75% efficiency. The unit price of electricity is 0.9 TL/kWh, and that of natural gas is 0.35 TL/kWh. The efficiency of your existing gas fired combi boiler is 80%. Accordingly, whether the heat pump or your existing combi boiler will heat your house more economically, specify the reason. Also draw the T-S diagram for the heat pump. Indicate the locations of the compressor, condenser and evaporator with the points on the diagram.

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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