A heat pump is installed in a building to heat the space to a constant 22 °C when the outdoor temperature is 15 °C. The heating requirement at these conditions is 30 kW. The system uses R-410a as a refrigerant and operates according to an ideal vapor compression cycle as shown in the figures below. The saturation temperature of the refrigerant in the indoor coil is typically 20 °C higher than the desired space temperature, and the saturation temperature of the refrigerant in the outdoor unit is typically 20 °C lower than the outdoor temperature. (one of those coils is the condenser, the other is the evaporator...you should be able to identify which one is positioned outside and which one is inside for this application)

A heat pump is installed in a building to heat the space to a constant 22 °C when the outdoor temperature is 15 °C. The heating requirement at these conditions is 30 kW. The system uses R-410a as a refrigerant and operates according to an ideal vapor compression cycle as shown in the figures below. The saturation temperature of the refrigerant in the indoor coil is typically 20 °C higher than the desired space temperature, and the saturation temperature of the refrigerant in the outdoor unit is typically 20 °C lower than the outdoor temperature. (one of those coils is the condenser, the other is the evaporator...you should be able to identify which one is positioned outside and which one is inside for this application)

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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Similar questions

The operating condition for the single compressor in a household refrigerator is the lowest box temperature, which is typically A. 0F B. -20F C. 20F D. 40F
A heat pump is installed in a building to heat the space to a constant 22 ⁰C when the outdoor temperature is 15 ⁰C. The heating requirement at these conditions is 30 kW. The system uses R-410a as a refrigerant and operates according to an ideal vapor compression cycle as shown in the figures below. The saturation temperature of the refrigerant in the indoor coil is typically 20 ⁰C higher than the desired space temperature, and the saturation temperature of the refrigerant in the outdoor unit is typically 20 ⁰C lower than the outdoor temperature. (one of those coils is the condenser, the other is the evaporator) Determine the states at points 1 through 4.
A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -30°C by rejecting waste heat to cooling water that enters the condenser at 20°C at a rate of 0.25 kg/s and leaves at 28°C. The refrigerant enters the condenser at 1.2 MPa and 50°C and leaves at the same pressure subcooled by 5°C. If the Talking PIYATIDA TENURUK compressor consumes 3.7 kW of power, determine (a) the mass flow rate of the refrigerant (b) the refrigeration load (c) the COP (d) the minimum power input to the compressor for the same refrigeration load
Refrigerant-134a enters the condenser of a steadyflow Carnot refrigerator as a saturated vapor at 90 psia, and it leaves with a quality of 0.05. The heat absorption from the refrigerated space takes place at a pressure of 30 psia. Show the cycle on a T-s diagram relative to saturation lines, and determine (a) the coefficient of performance, (b) the quality at the beginning of the heat-absorption process, and (c) the net work input.
HFC-134a is the working fluid of a steady-flow Carnot refrigerator. The refrigerant enters the condenser as a saturated vapor at 70ºF. Heat absorption from the refrigerated space takes place at a temperature of 10ºF. Determine the coefficient of performance of the cycle.
A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at –35°C by rejecting waste heat to cooling water that enters the condenser at 18°C at a rate of 0.25 kg/s and leaves at 26°C. The refrigerant enters the condenser at 1.2 MPa and 50°C and leaves at the same pressure subcooled by 5°C. If the compressor consumes 3.3 kW of power, determine the mass flow rate of the refrigerant,
A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at –35°C by rejecting waste heat to cooling water that enters the condenser at 18°C at a rate of 0.25 kg/s and leaves at 26°C. The refrigerant enters the condenser at 1.2 MPa and 50°C and leaves at the same pressure subcooled by 5°C. If the compressor consumes 3.3 kW of power, determine the refrigeration load.
A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at –35°C by rejecting waste heat to cooling water that enters the condenser at 18°C at a rate of 0.25 kg/s and leaves at 26°C. The refrigerant enters the condenser at 1.2 MPa and 50°C and leaves at the same pressure subcooled by 5°C. If the compressor consumes 3.3 kW of power, determine the COP,
A commercial refrigerator with refrigerant-134a as the working fluid is used to keep the refrigerated space at -30°C by rejecting its waste heat to cooling water that enters the condenser at 18°C at a rate of 0.25 kg/s and leaves at 26°C. The refrigerant enters the condenser at 1.2 MPa and 65°C and leaves at 42°C. The inlet state of the compressor is 60 kPa and -34 °C and the compressor is estimated to gain a net heat of 450 W from the surroundings. Determine (a) the quality of the refrigerant at the evaporator inlet (b) the refrigeration load in kW (c) the COP of the refrigerator (d) the theoretical maximum refrigeration load in kW for the same power input to the compressor. To obtain enthalpy values on the cooling water use steam tables.
A refrigerated room is kept at −18◦C by a vapor-compression cycle with R-134a as the refrigerant. Heat is rejected to cooling water that enters the condenser at 14◦C at a rate of 0.35 kg/s and leaves at 22◦C. The refrigerant enters the condenser at 1.2MPa and 50◦C and leaves at the same pressure subcooled by 5◦C. If the compressor consumes 5.5 kW of power, determine (a) the mass flow rate of the refrigerant, (b) the refrigeration load and the COP, (c) the second-law efficiency of the refrigerator and the total exergy destruction in the cycle, and (d) the exergy destruction in the condenser. Take specific heat of water to be 4.18 kJ/kg·◦C.
Consider a real compressor has an isentropic efficiency of 0.82. This refrigeration cycle has a condenser which over cools a liquid to a temperature of 46.3°C and an evaporator temperature of −8.6°C. The mixture changes to a liquid at a temperature of 48.8°C. Determine the coefficient of performance of this refrigerator for the working fluids of R-12,R-134a,and R-410a.
Consider a heat pump that operates on the vapor compression refrigeration cycle with R-134a as the working fluid. The refrigerant enters the compressor as saturated vapor at 100 kPa, and exits at 900 kPa and 70°C, and leaves the condenser as saturated liquid at 900 kPa. The coefficient of performance of this heat pump is