A heat pump with refrigerant R22 is used for space heating between temperature limits of -20°C and 25°C. The heat required is 200 MJ/h. Assume specific heat of vapour at the time of discharge as 0.98 kJ/kg.K. Other relevant properties are given below. The enthalpy (in kJ/kg) of the refrigerant at isentropic compressor discharge is Specific enthalpy Saturation temperature T. (°C) sat -20 25 Pressure P(MN/m²) 0.2448 1.048 h,(kJ/kg) 177.21 230.07 hg(kJ/kg) 397.53 413.02 Specific entropy S,(kJ/kg/K 0.9139 1.1047 S.(kJ/kg.K) 1.7841 1.7183

A heat pump with refrigerant R22 is used for space heating between temperature limits of -20°C and 25°C. The heat required is 200 MJ/h. Assume specific heat of vapour at the time of discharge as 0.98 kJ/kg.K. Other relevant properties are given below. The enthalpy (in kJ/kg) of the refrigerant at isentropic compressor discharge is Specific enthalpy Saturation temperature T. (°C) sat -20 25 Pressure P(MN/m²) 0.2448 1.048 h,(kJ/kg) 177.21 230.07 hg(kJ/kg) 397.53 413.02 Specific entropy S,(kJ/kg/K 0.9139 1.1047 S.(kJ/kg.K) 1.7841 1.7183

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

Chapter47: High-pressure, Low-pressure, And Absorption Chilled-water Systems

Section: Chapter Questions

Problem 13RQ: The subcooling temperature in a condenser can be measured by taking the difference between the A....

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