CDC 3E151P: Trivia Quiz On Heating, Ventilation And Refrigeration!
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What type of heat when added to a substance causes a measured temperature change without a change of state?
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Latent
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Specific
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Sensible
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Generic
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Welcome to the CDC 3e151p trivia Quiz on heating, ventilation, and Refrigeration. This course teaches you how to store food and maintain heat in different situations, considering one would not know where they are posted or would end up. Take it up and get to see what your chances of survival are even batting camp. All the best in the See moreexams!
Quiz Preview
- 2.
In which two parts of a refrigeration system does a pressure change take place?
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Condenser and evaporator
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Compressor and evaporator
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Condenser and metering device
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Compressor and metering device
Correct Answer
A. Compressor and metering deviceExplanation
In a refrigeration system, a pressure change takes place in the compressor and metering device. The compressor is responsible for increasing the pressure of the refrigerant gas, while the metering device is responsible for reducing the pressure of the refrigerant as it enters the evaporator. This pressure change is essential for the refrigeration cycle to work effectively, as it allows the refrigerant to absorb heat in the evaporator and release it in the condenser.Rate this question:
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- 3.
What is the line to inlet relationship of refrigerant vapor travel as it leaves the evaporator?
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Suction to condenser
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Suction to compressor
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Discharge to condenser
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Discharge to compressor
Correct Answer
A. Suction to compressorExplanation
The correct answer is "Suction to compressor." This means that the refrigerant vapor travels from the suction line to the compressor after leaving the evaporator. The suction line is responsible for carrying the low-pressure vapor from the evaporator to the compressor, where it is compressed and then sent to the condenser.Rate this question:
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- 4.
Which processes take place inside the condenser?
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Desuperheating and compression
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Desuperheating and condensing
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Vaporization and desuperheating
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Vaporization and condensing
Correct Answer
A. Desuperheating and condensingExplanation
Inside the condenser, two processes take place: desuperheating and condensing. Desuperheating refers to the process of removing excess heat from the superheated vapor, reducing its temperature to the saturation point. Condensing, on the other hand, involves the transformation of the vapor into a liquid state by removing heat, resulting in the release of latent heat. These processes are essential in the condenser as they help in the transfer of heat from the vapor to the cooling medium, allowing the vapor to be converted back into a liquid state.Rate this question:
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- 5.
The reciprocating refrigeration compressor is designed to remove
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Vapor refrigerant from the condenser and decrease the pressure
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Vapor refrigerant from the evaporator and increase the pressure
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Liquid refrigerant from the condenser and increase the pressure
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Liquid refrigerant from the evaporator and increase the pressure
Correct Answer
A. Vapor refrigerant from the evaporator and increase the pressureExplanation
The reciprocating refrigeration compressor is designed to remove vapor refrigerant from the evaporator and increase the pressure. This is because the compressor plays a crucial role in the refrigeration cycle by compressing the low-pressure vapor refrigerant from the evaporator and raising its pressure. This high-pressure vapor refrigerant is then sent to the condenser where it releases heat and condenses into a high-pressure liquid refrigerant. Therefore, the compressor's function is to increase the pressure of the vapor refrigerant from the evaporator, not from the condenser or the liquid refrigerant.Rate this question:
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- 6.
Which component is installed at the inlet of the evaporator?
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Metering device
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Accumulator
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Compressor
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Condenser
Correct Answer
A. Metering deviceExplanation
The metering device is installed at the inlet of the evaporator. This component is responsible for regulating the flow of refrigerant into the evaporator, ensuring that the correct amount of refrigerant enters the evaporator coil. It controls the pressure and flow rate of the refrigerant, allowing it to expand and cool down as it passes through the evaporator. By controlling the flow of refrigerant, the metering device helps to maintain the desired temperature and pressure levels within the evaporator, ensuring efficient and effective cooling.Rate this question:
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- 7.
In which major component does absorbed heat cause liquid refrigerant to boil?
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Metering device
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Compressor
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Condenser
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Evaporator
Correct Answer
A. EvaporatorExplanation
When absorbed heat is applied to the liquid refrigerant, it causes the refrigerant to boil. This process occurs in the evaporator, which is a major component of a refrigeration system. The evaporator is responsible for absorbing heat from the surrounding environment, such as the air in a room or the contents of a refrigerator. As the absorbed heat is transferred to the refrigerant, it causes the liquid refrigerant to evaporate and turn into a gas. This gas then travels to the compressor, where it is pressurized and further heated before entering the condenser.Rate this question:
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- 8.
Which major component is considered to be the “heart” of the refrigeration system?
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Metering device
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Compressor
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Evaporator
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Condenser
Correct Answer
A. CompressorExplanation
The compressor is considered to be the "heart" of the refrigeration system because it plays a crucial role in the refrigeration cycle. It is responsible for compressing the refrigerant gas, which increases its temperature and pressure. This high-pressure gas then flows to the condenser where it releases heat and condenses into a high-pressure liquid. The compressor also helps to circulate the refrigerant throughout the system, ensuring efficient cooling. Without the compressor, the refrigeration system would not be able to function properly.Rate this question:
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- 9.
Which refrigeration compressor is equipped with pistons and connecting rods?
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Screw
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Scroll
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Centrifugal
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Reciprocating
Correct Answer
A. ReciprocatingExplanation
A reciprocating refrigeration compressor is equipped with pistons and connecting rods. This type of compressor uses a piston-cylinder arrangement to compress the refrigerant gas. The piston moves back and forth in the cylinder, creating a suction stroke to draw in the refrigerant and a compression stroke to compress the refrigerant. The connecting rod connects the piston to the crankshaft, allowing the reciprocating motion. This type of compressor is commonly used in small to medium-sized refrigeration systems.Rate this question:
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- 10.
Which type piston can suction gas pass through?
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Plug
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Trunk
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Plate
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Forged
Correct Answer
A. TrunkExplanation
A trunk piston is designed with a hollow space in the center called a trunk, which allows gas to pass through. This type of piston is commonly used in internal combustion engines where the fuel-air mixture is drawn into the combustion chamber through the trunk. The other options, such as plug, plate, and forged pistons, do not have this feature and therefore do not allow gas to pass through.Rate this question:
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- 11.
How does the rotary compressor compress the refrigerated vapor?
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Rotating action
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Squeezing action
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Increasing the volume
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Decreasing the pressure
Correct Answer
A. Squeezing actionExplanation
The rotary compressor compresses the refrigerated vapor through a squeezing action. As the rotary blades rotate, they create a tight seal with the compressor housing, trapping the vapor inside. As the blades continue to rotate, the vapor is squeezed and compressed, resulting in an increase in pressure. This squeezing action allows the compressor to effectively compress the vapor and move it through the refrigeration system.Rate this question:
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- 12.
What type of rotary compressor has the blade set into the cylinder?
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Multiblade
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Movable blade
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Stationary blade
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Eccentric roller blade
Correct Answer
A. Stationary bladeExplanation
A rotary compressor with a stationary blade has the blade set into the cylinder. This means that the blade is fixed in position and does not move during operation. This type of compressor design allows for efficient compression of gases or fluids as they pass through the cylinder. The stationary blade creates a seal that helps to prevent leakage and ensures that the compression process is effective.Rate this question:
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- 13.
Which compressor type is used with refrigerants that have a large gas volume?
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Recipricating
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Centrifugal
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Screw
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Scroll
Correct Answer
A. CentrifugalExplanation
Centrifugal compressors are used with refrigerants that have a large gas volume because they are capable of handling high flow rates and can efficiently compress large volumes of gas. These compressors use centrifugal force to accelerate the refrigerant gas and then convert the kinetic energy into pressure energy. This makes them suitable for applications where a large volume of gas needs to be compressed, such as in large-scale industrial refrigeration systems or air conditioning units.Rate this question:
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- 14.
Which type of compressor uses an orbiting motion for compression?
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Reciprocating
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Rotary
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Screw
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Scroll
Correct Answer
A. ScrollExplanation
A scroll compressor uses an orbiting motion for compression. In a scroll compressor, two spiral-shaped scrolls are used, one fixed and one orbiting. The orbiting scroll moves in a circular motion, creating a series of gas pockets that gradually decrease in size, compressing the gas. This design allows for smooth and efficient compression without the need for valves or pistons, making scroll compressors popular for applications requiring quiet operation and high efficiency.Rate this question:
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- 15.
Heat that is picked up in the refrigeration system is rejected at the
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Condenser
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Evaporator
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Compressor
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Metering devices
Correct Answer
A. CondenserExplanation
The heat that is picked up in the refrigeration system is rejected at the condenser. The condenser is responsible for transferring heat from the refrigerant to the surrounding environment, causing the refrigerant to condense back into a liquid state. This process releases the heat that was absorbed from the cooled space, allowing the refrigerant to be ready for another cycle of cooling.Rate this question:
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- 16.
The advantage of an air-cooled condenser is
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Greater operating cost
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Higher head pressure
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Fans that can become noisy
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Less maintenance
Correct Answer
A. Less maintenanceExplanation
An air-cooled condenser has the advantage of requiring less maintenance compared to other types of condensers. This is because it does not use water or other fluids for cooling, eliminating the need for regular maintenance and potential issues such as leaks or corrosion. The absence of fluid also reduces the risk of contamination and the need for monitoring and treating the fluid. Overall, this results in lower maintenance costs and less time spent on upkeep, making air-cooled condensers a more convenient and cost-effective option.Rate this question:
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- 17.
The disadvantage of water-cooled condensers is
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Lower head pressure
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High heat transfer.
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Compactness
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Higher cost
Correct Answer
A. Higher costExplanation
Water-cooled condensers have the disadvantage of higher cost compared to other types of condensers. This is because water-cooled condensers require additional equipment such as water pumps, cooling towers, and water treatment systems, which can increase the overall cost of the system. Additionally, the installation and maintenance of water-cooled condensers can also be more expensive compared to other types of condensers. Therefore, the higher cost is a drawback of water-cooled condensers.Rate this question:
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- 18.
Which type of water-cooled condenser has removable heads that allow the tubes to be cleaned out with a revolving brush?
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Tube-within-a-tube.
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Shell-and-tube.
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Shell-and-coil.
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Double-tube.
Correct Answer
A. Shell-and-tube.Explanation
A shell-and-tube water-cooled condenser has removable heads that allow the tubes to be cleaned out with a revolving brush. This design allows for easy maintenance and cleaning of the condenser tubes, ensuring efficient heat transfer and preventing any blockages or build-up of debris. The removable heads provide access to the tubes, allowing for thorough cleaning and maintenance to keep the condenser operating effectively.Rate this question:
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- 19.
The thermostatic expansion valve maintains a fully active evaporator by
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Reducing heat load
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Enhancing condensation.
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Maintaining the proper amount of superheat.
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Maintaining the proper amount of subcooling.
Correct Answer
A. Maintaining the proper amount of superheat.Explanation
The thermostatic expansion valve is responsible for regulating the flow of refrigerant into the evaporator coil. It maintains the proper amount of superheat by controlling the amount of refrigerant entering the evaporator. Superheat is the temperature of the refrigerant vapor above its boiling point, and it ensures that the refrigerant is completely vaporized before leaving the evaporator. By maintaining the proper amount of superheat, the thermostatic expansion valve ensures efficient and effective cooling by preventing liquid refrigerant from entering the compressor, which could cause damage.Rate this question:
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- 20.
Complete vaporization in an evaporator occurs at point
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C
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G
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S
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V
Correct Answer
A. V -
- 21.
What type of thermostatic expansion valve has a bulb that is charged with fluid that is different from the refrigerant in the system?
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Gas
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Cross
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Liquid
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Special
Correct Answer
A. CrossExplanation
A cross type thermostatic expansion valve has a bulb that is charged with fluid that is different from the refrigerant in the system. This design allows for better control and regulation of the refrigerant flow, as the bulb senses the temperature of the refrigerant and adjusts the valve accordingly. By using a different fluid in the bulb, the valve can accurately respond to changes in temperature and maintain the desired level of refrigerant flow.Rate this question:
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- 22.
What type of thermostatic expansion valve has a charged sensing bulb that presents the danger of flood-back?
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Gas
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Cross
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Liquid
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Special
Correct Answer
A. LiquidExplanation
A thermostatic expansion valve with a charged sensing bulb that contains liquid presents the danger of flood-back. This is because the liquid-filled sensing bulb can cause the valve to open too quickly, leading to an excessive flow of refrigerant into the evaporator. This can result in liquid refrigerant entering the compressor, causing damage and potentially leading to flood-back.Rate this question:
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- 23.
To create the required pressure drop, the capillary tube uses a designed
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Reactance
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Resistance
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Flow increase
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Pressure increase
Correct Answer
A. ResistanceExplanation
The capillary tube uses resistance to create the required pressure drop. Resistance refers to the obstruction or hindrance to the flow of fluid through a tube or pipe. In this case, the capillary tube is designed in a way that it offers a certain level of resistance to the flow of fluid, causing a pressure drop. This pressure drop is necessary for various applications such as controlling the flow rate or regulating the pressure within a system.Rate this question:
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- 24.
How is the capillary tube in a system affected by the refrigerant charge?
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The refrigerant charge is critical
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The refrigerant pressure can fluctuate.
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The system can take extra refrigerant.
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The system can take a less amount of refrigerant.
Correct Answer
A. The refrigerant charge is criticalExplanation
The capillary tube in a system is affected by the refrigerant charge because the refrigerant charge refers to the amount of refrigerant present in the system. If the refrigerant charge is not at the correct level, it can cause issues with the operation of the capillary tube. If there is too much refrigerant, it can lead to excessive pressure and potentially damage the capillary tube. On the other hand, if there is too little refrigerant, it can result in insufficient cooling and reduced efficiency of the capillary tube. Therefore, the refrigerant charge being critical means that it needs to be at the correct level for the capillary tube to function properly.Rate this question:
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- 25.
The direct-expansion evaporator picks up or absorbs heat directly from the
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Outside air
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Conditioned space
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Primary refrigerant
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Secondary refrigerant
Correct Answer
A. Conditioned spaceExplanation
The direct-expansion evaporator is responsible for picking up or absorbing heat directly from the conditioned space. This means that it extracts heat from the air in the area being cooled and transfers it to the refrigerant. This process allows the evaporator to cool down the conditioned space by removing the heat from it.Rate this question:
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- 26.
Which evaporator operating condition uses air circulation to aid in defrosting?
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Frosting.
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Defrosting.
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Nonfrosting.
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Partial frosting.
Correct Answer
A. Defrosting.Explanation
Defrosting is the correct answer because it involves the use of air circulation to aid in removing frost or ice buildup on the evaporator. This process helps to melt the frost or ice faster and more efficiently, allowing the evaporator to resume its normal cooling function.Rate this question:
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- 27.
Which evaporator type is designed to maintain an even temperature throughout the refrigerated space?
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Bare-tube.
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Finned-tube.
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Forced-convection.
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Natural-convection.
Correct Answer
A. Forced-convection.Explanation
Forced-convection evaporators are designed to maintain an even temperature throughout the refrigerated space. This type of evaporator uses a fan or blower to circulate air over the evaporator coil, ensuring that the cold air is evenly distributed throughout the space. This helps to prevent hot spots or cold spots in the refrigerated area, providing consistent cooling and maintaining a uniform temperature. Bare-tube and finned-tube evaporators do not have the same level of air circulation, while natural-convection evaporators rely on the natural movement of air, which may not be as effective in maintaining an even temperature.Rate this question:
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- 28.
Which cooler is used exclusively to cool liquids?
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Baudelot
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Tank-type.
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Shell-and-coil.
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Shell-and-tube.
Correct Answer
A. BaudelotExplanation
The Baudelot cooler is used exclusively to cool liquids. It is a type of heat exchanger that consists of a bundle of tubes through which the liquid flows, while the cooling medium, usually water, circulates around the tubes. This design allows for efficient heat transfer between the liquid and the cooling medium, effectively cooling the liquid. The other options, tank-type, shell-and-coil, and shell-and-tube, may be used for various cooling applications but are not exclusively designed for cooling liquids.Rate this question:
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- 29.
Which type of cooler is generally used in the common water cooler?
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Shell-and-coil.
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Shell-and-tube.
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Baudelot.
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Tank-type.
Correct Answer
A. Shell-and-coil.Explanation
Shell-and-coil coolers are generally used in common water coolers. This type of cooler consists of a coil inside a shell. The water flows through the coil, while the cooling medium, usually air, circulates around the coil inside the shell. This design allows for efficient heat transfer between the water and the cooling medium, resulting in effective cooling of the water. Shell-and-coil coolers are commonly used in water coolers due to their compact size, high heat transfer efficiency, and ease of maintenance.Rate this question:
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- 30.
Refrigerants containing chlorine are said to destroy
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Ozone
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Carbon
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Oxygen
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Nitrogen
Correct Answer
A. OzoneExplanation
Refrigerants containing chlorine are said to destroy ozone because chlorine atoms can react with ozone molecules in the stratosphere. This reaction results in the breakdown of ozone, leading to the depletion of the ozone layer. This is a significant environmental concern as the ozone layer plays a crucial role in protecting the Earth from harmful ultraviolet (UV) radiation. The destruction of ozone can lead to increased UV radiation reaching the Earth's surface, which can have detrimental effects on human health and ecosystems.Rate this question:
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- 31.
R–406a can be used to replace
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R–502.
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R–113.
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R–22.
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R–12.
Correct Answer
A. R–12.Explanation
R-406a can be used to replace R-12 refrigerant. R-12, also known as dichlorodifluoromethane, is a hydrochlorofluorocarbon (HCFC) refrigerant that has been phased out due to its harmful effects on the ozone layer. R-406a, also known as azeotropic mixture, is a hydrofluorocarbon (HFC) refrigerant that does not harm the ozone layer. It has similar properties to R-12 and can be used as a drop-in replacement in existing systems designed for R-12.Rate this question:
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- 32.
Temperature glide in an zeotropic refrigerant means that the refrigerant is a
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Blend that acts as one inside the refrigeration system.
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Mixture that acts as one while inside the refrigeration system.
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Blend that evaporates and condenses over a range of temperatures instead of a single temperature.
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Mixture that liquefies and vaporizes over a range of temperatures instead of a single temperature.
Correct Answer
A. Blend that evaporates and condenses over a range of temperatures instead of a single temperature.Explanation
Temperature glide in a zeotropic refrigerant refers to the phenomenon where the refrigerant blend evaporates and condenses over a range of temperatures instead of a single temperature. This means that different components of the blend have different boiling and condensing points, causing the blend to behave as a mixture rather than a single substance. As a result, the refrigerant's properties change gradually as it goes through the evaporation and condensation processes, leading to a temperature glide.Rate this question:
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- 33.
Which of these refrigerants has an ozone depletion rating of zero?
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R-12
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R-22
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R-134a
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R-500
Correct Answer
A. R-134aExplanation
R-134a is the correct answer because it has an ozone depletion rating of zero. This means that it does not contribute to the depletion of the ozone layer. R-12 and R-22, on the other hand, have ozone depletion potentials and can contribute to ozone depletion. R-500 is a blend of refrigerants and does not have a zero ozone depletion rating.Rate this question:
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- 34.
The Environmental Protection Agency (EPA) has developed a Significant New Alternatives Policy (SNAP) Program. This program is used to determine
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Whether the alternative refrigerant provides adequate performance
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The risks that alternative refrigerants pose to human health and the environment.
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Whether the alternative refrigerant is compatible with components of the system.
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The procedures necessary for retrofitting with refrigerants on the SNAP Program list.
Correct Answer
A. The risks that alternative refrigerants pose to human health and the environment.Explanation
The SNAP Program developed by the EPA is used to determine the risks that alternative refrigerants pose to human health and the environment. This suggests that the program focuses on evaluating the potential negative effects of using alternative refrigerants on both human health and the environment. The program likely assesses the potential for these refrigerants to contribute to air pollution, ozone depletion, or climate change, and considers the potential health risks associated with their use.Rate this question:
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- 35.
Which organization requires that a comprehensive risk assessment be performed to estimate the likelihood of fire and potential results should a fire occur when alternative refrigerants contain a flammable component?
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Air-Conditioning and Refrigeration Institute (ARI).
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Environmental Protection Agency (EPA).
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American Society of Testing Materials (ASTM).
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American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE).
Correct Answer
A. Environmental Protection Agency (EPA).Explanation
The correct answer is the Environmental Protection Agency (EPA). The EPA requires a comprehensive risk assessment to be performed to estimate the likelihood of fire and potential results should a fire occur when alternative refrigerants contain a flammable component. This is likely because the EPA is responsible for regulating and protecting the environment, including the safety and potential hazards associated with refrigerants.Rate this question:
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- 36.
What is the maximum fine and jail sentence that service technicians may be subject to for charging a system with an unacceptable refrigerant?
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$10,000 and 5 years.
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$10,000 and 10 years.
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$25,000 and 5 years.
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$25,000 and 10 years.
Correct Answer
A. $25,000 and 5 years.Explanation
Service technicians may be subject to a maximum fine of $25,000 and a jail sentence of up to 5 years for charging a system with an unacceptable refrigerant.Rate this question:
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- 37.
Which of these refrigerants is colorless and has a very pronounced odor?
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R–718.
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R–717.
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R–504.
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R–123.
Correct Answer
A. R–717.Explanation
R-717, also known as ammonia, is a colorless refrigerant with a very pronounced odor. Ammonia is commonly used in industrial refrigeration systems due to its excellent thermodynamic properties. However, its strong smell makes it easily detectable in case of leaks, which is an important safety feature.Rate this question:
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- 38.
What is the maximum percent a refillable cylinder can be refilled with refrigerant?
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85
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80
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75
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70
Correct Answer
A. 80Explanation
A refillable cylinder can be refilled with a maximum of 80% of refrigerant. This means that the cylinder should not be filled beyond this percentage to ensure safety and proper functioning. Filling it beyond this limit may cause issues such as overpressure or leakage, which can be dangerous. Therefore, it is important to adhere to the maximum refill percentage to maintain the cylinder's integrity and prevent any potential hazards.Rate this question:
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- 39.
A good refrigerant oil will have
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A high pour point
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Thermal instability
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Chemical reaction.
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Low viscosity.
Correct Answer
A. Low viscosity.Explanation
A good refrigerant oil should have low viscosity because it needs to flow easily through the refrigeration system to ensure efficient heat transfer and lubrication. If the oil has high viscosity, it may cause resistance to flow, leading to reduced cooling capacity and increased energy consumption. Additionally, low viscosity helps the oil to circulate effectively and reach all the necessary components in the system, ensuring proper lubrication and preventing wear and tear. Therefore, low viscosity is an important characteristic for a good refrigerant oil.Rate this question:
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- 40.
Which refrigerant oil is designed for use with the new ternary blend refrigerants?
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Ester
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Mineral
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Polyalkylene glycol
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Alkyl benzene oil
Correct Answer
A. Alkyl benzene oilExplanation
Alkyl benzene oil is designed for use with the new ternary blend refrigerants. This type of refrigerant oil is compatible with these specific blend refrigerants and is formulated to provide optimal performance and efficiency in refrigeration systems that use them.Rate this question:
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- 41.
Cleaning a refrigerant at the job site or at a local service shop is called
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Recycling.
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Reclamation.
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Redeeming.
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Recovery.
Correct Answer
A. Recycling.Explanation
The process of cleaning a refrigerant either at the job site or at a local service shop is referred to as recycling. This involves removing any impurities or contaminants from the refrigerant so that it can be reused. Recycling helps to minimize waste and promotes the sustainable use of resources. Reclamation refers to the process of restoring a refrigerant to its original state, while redeeming and recovery are not relevant to the context of cleaning a refrigerant.Rate this question:
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- 42.
On systems that contain over how many pounds of refrigerant is passive recovery not authorized?
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7.5
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10
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12
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15
Correct Answer
A. 15Explanation
Passive recovery is not authorized on systems that contain over 15 pounds of refrigerant. This means that for systems with a refrigerant quantity exceeding 15 pounds, a different method of recovery must be used instead of passive recovery.Rate this question:
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- 43.
On Type II systems, what level of evacuation in the isolated component must be attained when you are making minor repairs of items such as a filter-drier or a strainer?
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0 pounds per square inch gauge (psig).
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5 psig.
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4 inches of mercury.
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10 inches of mercury.
Correct Answer
A. 0 pounds per square inch gauge (psig).Explanation
When making minor repairs on Type II systems, such as replacing a filter-drier or a strainer, the level of evacuation required in the isolated component is 0 pounds per square inch gauge (psig). This means that the component should be completely free of any pressure. This is necessary to ensure that no air or moisture is present in the system, which could negatively affect its performance and efficiency. By achieving a vacuum level of 0 psig, any potential contaminants can be effectively removed, allowing for proper functioning of the system after the repairs are made.Rate this question:
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- 44.
Commercial and industrial systems with leaks exceeding what percent per year will require repair?
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5
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15
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25
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35
Correct Answer
A. 35Explanation
Commercial and industrial systems with leaks exceeding 35% per year will require repair. This means that if the leaks in these systems exceed 35% of the total volume per year, they will need to be fixed. A leak exceeding this percentage indicates a significant problem that needs to be addressed in order to ensure the proper functioning and efficiency of the systems.Rate this question:
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- 45.
R–401A is not a suitable alternative refrigerant for
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Walk-in coolers.
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Home refrigerators.
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Supermarket display cases.
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Residential air conditioners.
Correct Answer
A. Residential air conditioners.Explanation
R-401A is not a suitable alternative refrigerant for residential air conditioners because it is not compatible with the specific requirements and operating conditions of these cooling systems. It may not provide optimal cooling performance or efficiency, and could potentially cause damage or malfunction in the residential air conditioning units. Therefore, it is important to use a refrigerant that is specifically designed and recommended for residential air conditioners to ensure proper functioning and longevity of the equipment.Rate this question:
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- 46.
R–401A and B can be described as a/an
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Blend-type alternative
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Azeotrope alternative.
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Chlorofluorocarbon (CFC)-based alternative.
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Hydrofluorocarbon (HFC)-based alternative.
Correct Answer
A. Hydrofluorocarbon (HFC)-based alternative.Explanation
R-401A and B are described as hydrofluorocarbon (HFC)-based alternatives. This means that they are alternatives that use HFCs as their main components. HFCs are a type of synthetic refrigerant that do not contain chlorine, making them less harmful to the ozone layer compared to chlorofluorocarbons (CFCs). HFC-based alternatives are commonly used in refrigeration and air conditioning systems as a more environmentally friendly option.Rate this question:
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- 47.
Which alternative replacement for R–502 is a patented azeotrope?
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R–507
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R–409A
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R–404A
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R–402A
Correct Answer
A. R–507Explanation
R-507 is a patented azeotrope that can be used as an alternative replacement for R-502. Azeotropes are mixtures of two or more substances that behave like a single substance, meaning they have a constant boiling point and composition. R-507 is a blend of hydrofluorocarbons (HFCs) that has been specifically formulated to mimic the properties of R-502, making it a suitable replacement for this refrigerant.Rate this question:
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- 48.
You are retrofitting a system that does not have a receiver. To do the job properly, you would store the refrigerant in
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A recovery cylinder
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The compressor
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The condenser
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The evaporator
Correct Answer
A. A recovery cylinderExplanation
When retrofitting a system that does not have a receiver, it is important to store the refrigerant in a recovery cylinder. This is because a recovery cylinder is designed specifically for storing refrigerants safely and securely. It allows for proper containment and disposal of the refrigerant during the retrofitting process. Storing the refrigerant in the compressor, condenser, or evaporator would not be appropriate or safe in this situation.Rate this question:
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- 49.
When polyolester oil is used in place of mineral oil during a retrofit procedure, you must make sure that less than what percent of mineral oil can remain in the system?
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5
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4
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3
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2
Correct Answer
A. 5Explanation
During a retrofit procedure, when polyolester oil is used instead of mineral oil, it is important to ensure that less than 5% of mineral oil remains in the system. This is because the two types of oil are not compatible and can cause issues if they mix. Therefore, it is necessary to thoroughly flush the system and remove as much mineral oil as possible to avoid any potential problems.Rate this question:
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Mar 20, 2023Quiz Edited by
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Nov 03, 2012Quiz Created by
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