Partial preview of the text
Download Basic Refrigeration Final Exam with Questions and Answers and more Exams Refrigeration and Air Conditioning in PDF only on Docsity!
Refrigerant in liquid form is normally put into the system through the when the system is in a vacuum. A. Liquid return line B. Suction line C. Liquid line D. Hot gas line ANSWER VV C. Liquid line A flooded evaporator will cause which symptom? A. male pattern baldness B. high or extensive superheat C. low or no superheat D. high compressor amps ANSWER VV C. Low or no superheat Fractionation occurs when A. The operating pressures of a system increase. B. both a and c. C. when only a fraction of the total charge has been added to a system. D. some of a blended refrigerant evaporates or condenses before the rest of the blend. ANSWER V VJ D. Some of a blended refrigerant evaporates or condenses before the rest of the blend. The household refrigerator fresh-food compartment is a good example of. refrigeration. A. Medium-temperature B. Average-temperature C. Low-temperature D. High-temperature ANSWER VV A. Medium-temperature A refrigeration system designed for the storage of flowers or candy is considered a type. A. Low temperature B. High temperature C. Sharp freezing D. Medium temperature ANSWER VV B. High temperature The in a refrigeration system is responsible for absorbing heat into the system from whatever medium is to be cooled. A. Evaporator B. Condenser C. Compressor D. Thermostat ANSWER VV A. Evaporator The boiling temperature and its relationship to the system exist in the A. Thermostat B. Compressor C. Evaporator and condenser C. Wait, I'll ask SIRT D. Moisture left in the system ANSWER VV D. Moisture left in the system Ifan R-12 refrigeration system has its air-cooled condensing unit on a 100°F roof and the condenser outlet temperature (refrigerant) is | 15°F, with how much sub-cooling is the condenser operating? A. 130F B. 100 F C.15F D.30F ANSWER VV C. ISF Which of the following compressor type is completely sealed? A. Open drive B. Semi hermetic C. Rotary D. Hermetic ANSWER VV D. Hermetic What should be done with the refrigerant after a compressor failure? A. Sent in for disposal B. Reclaim it C. Sell to your best friend D. Recycle it E. Vent it ANSWER VV A. Sent in for disposal The state of the refrigerant entering the compressor is é A. High pressure, high temperature superheated from the condenser. B. Subcooled from the evaporator. C. Subcooled from the condenser. D. Low pressure, low temperature superheated from the evaporator. ANSWER VJ D. Low pressure, low temperature superheated from the evaporator. The temperature of the compressed gas leaving the compressor can best be described as__. A. Cool B. Cold C. Warm D. Freakin hot ANSWER Vv C. Warm Using a P/T chart, what is the pressure of R22 at 40 F? A. 0 PSIG B. 69 PSIG C. Wait, I'll ask SIRT D. 40 PSIG ANSWER V¥ B. 69 PSIG When the load on the evaporator increases, the TXV__ A. Increases the flow of refrigerant. B. Decreases the pressure drop across the evaporator. C. Maintains constant head pressure. D. Decreases the flow of refrigerant. ANSWER V/V A. Increases the flow of refrigerant. B. False ANSWER VV B. False As the pressure in the evaporator increases, an automatic expansion valve closes. A. Truc B. False ANSWER VV A. True Reclaimed refrigerant may be sold to another customer. A. True B. False ANSWER VV B. False The sight glass on the liquid line indicates moisture and other contamination. A, True B. False ANSWER VV A. True The compressor can compress liquid? A. True B. False ANSWER V ¥ B. False The hermetic reciprocating compressor motor is essentially made of the same materials as an semi-hermetic type compressor motor. A. True B. False ANSWER VV B. False Systems that use capillary type metering devices should never be checked with superheat. A. True B. False ANSWER V ¥ B. False ligh temperature refrigeration is that produced by ___ A. Heat from a furnace B. The freezer section of a refrigerator C. An air-conditioning system D. The vegetable cooling system of a refrigerator ANSWER VV C. An air-conditioning system The relationship correlates the vapor pressure and the boiling pressure of water and is the basis for controlling the cooling system's temperatures. A. Boiling/Vapor B. Temperature/Pressure C. Temperature/Vapor D. Boiling/Pressure ANSWER ¥V V B. Temperature/Pressure Reciprocating compressors have A. A large fan compressor component B. A piston and cylinder C. Two scrolls that mesh together D. A rotor to compress the refrigerant ANSWER ¥ V B. A piston and cylinder D. Are desirable in a refrigeration system. ANSWER VV A. Are undesirable in a refrigeration system. To pull a vacuum means to A. Lower the pressure in a refrigeration system below atmosphere. B. Condense the gas in the system. C. Allow refrigerant to escape into the atmosphere. D. Raise the pressure in a refrigeration system. ANSWER V V A. Lower the pressure in a refrigeration system below atmosphere. A micron gague is used to measure AA. Atmospheric pressure at high altitudes. B. Absolute pressure below 1 mm Hg. C. Atmospheric pressures at sea level. D. High pressure in a refrigeration system. ANSWER V J B. Absolute pressure below 1 mm Hg. Which of the following represents the deepest vacuum? A. 5 psig B. 10 psia C. 500 microns D. 5" Hg VAC ANSWER VV C. 500 microns A multiple evacuation means that : A. You pull a vacuum on three different systems at the same time. B. You pull a vacuum on a refrigeration system more than once, allowing dry nitrogen into the system between cach procedure. C. There must be more than one system operating before a vacuum can be pulled. D. You connect three vacuum pumps simultaneously to a refrigeration system and pull a vacuum. ANSWER V ¥ B. You pull a vacuum on a refrigeration system more than once, allowing dry nitrogen into the system between each procedure. Refrigerant that has both vapor and liquid, and heat is added, the refrigerant will: A. Saturated. B. Smell Bad. C. Will need to be filtered. D. Have subcooling. ANSWER VV A. Saturated Which of the following refrigerants is a CFC-type of refrigerant? A. R-134a B. R-12 C. R-123 D. R-22 ANSWER VV B. R-12 Which of the following refrigerant has the highest Ozone Depletion Potential (ODP)? A. HCFC B. CFC C. HFC A. 15 Nove 1993 B. 15 Nov 1995 C. 6 Aug 1966 D. 14 Nov 1994 ANSWER VV B. 15 Nov 1995 
