1. the wire drawing effect on pressure in the compressor done at: A. discharge valve pressure. B. suction valve pressure. C. dearance volumetric efficiency. 2. Fusion heat is heat used to: A. change the state from liquid to vapor. B. change the state from solid to liquid. C. change the state from solid to vapor. 3. In order to improve the first principle of refrigeration: A. temperature of fluid used to absorb the heat must be colder than the space temperature. B. temperature of fluid used to reject the heat must be warmer than the ambient temperature. C. temperature of fluid used to absorb/reject heat must be equal the ambient temperature. 4. Phase change required large amount of energy mean: A. The heat transfer area is small. B. the temperature and pressure keep constant. C. both a and b. 5. the pressure appear in gauge of vapor compression refrigeration cycle is due to: A. the system circulation pressure. B. the vapor of the fluid. C. the increase in the temperature.

1. the wire drawing effect on pressure in the compressor done at: A. discharge valve pressure. B. suction valve pressure. C. dearance volumetric efficiency. 2. Fusion heat is heat used to: A. change the state from liquid to vapor. B. change the state from solid to liquid. C. change the state from solid to vapor. 3. In order to improve the first principle of refrigeration: A. temperature of fluid used to absorb the heat must be colder than the space temperature. B. temperature of fluid used to reject the heat must be warmer than the ambient temperature. C. temperature of fluid used to absorb/reject heat must be equal the ambient temperature. 4. Phase change required large amount of energy mean: A. The heat transfer area is small. B. the temperature and pressure keep constant. C. both a and b. 5. the pressure appear in gauge of vapor compression refrigeration cycle is due to: A. the system circulation pressure. B. the vapor of the fluid. C. the increase in the temperature.

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

Chapter50: Commercial, Packaged Rooftop, Variable Refrigerant Flow, And Variable Air Volume Systems

Section: Chapter Questions

Problem 22RQ: Variable refrigerant flow systems sense the ______and _____of the refrigerant to determine the...

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