3B2 E2.5 C10 Review

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Which class of refrigerants is non-toxic and non-flammable?

Class A (correct)

Class B

Class 1

Class 3

What is the heat of combustion threshold that classifies a refrigerant as a Class 2 refrigerant?

Equal to 0.10 kJ/kg

Less than 19,000 kJ/kg (correct)

Less than 0.10 kJ/kg

Greater than 0.10 kJ/kg

Which refrigerant is a member of the HCFC group and is highly stable?

Refrigerant R-12 (correct)

Ammonia

Refrigerant R-134a

Refrigerant R-22

At what temperature does Refrigerant R-12 boil at atmospheric pressure?

-29.8°C Signup and view all the answers

What is a property that makes Refrigerant R-12 suitable for various temperature applications?

Oil miscibility Signup and view all the answers

What effect does R-12 have on the earth's ozone layer and greenhouse effect?

Contributes to depletion of ozone layer Signup and view all the answers

Which refrigerant has been widely used in automotive air conditioning systems?

Refrigerant R-12 Signup and view all the answers

What is the primary use of Refrigerant R-22 today?

Packaged air conditioners Signup and view all the answers

Which category of refrigerants has a higher flammability limit than 0.10 kg/m3?

Class 1 Signup and view all the answers

What could be a reason that synthetic oils are used with R-22?

To alleviate oil separation Signup and view all the answers

Which refrigerant is being used to replace R-12 in automotive air conditioning systems?

R-134a Signup and view all the answers

Which refrigerant is the only one outside of the fluorocarbon group that is used to a great extent?

R-717 Signup and view all the answers

Which refrigerant has a boiling point of -33.3°C at atmospheric pressure?

R-717 Signup and view all the answers

Which refrigerant is non-flammable and non-explosive?

R-134a Signup and view all the answers

Which refrigerant is not miscible in oil and does not dilute the oil in the compressor crankcase?

R-717 Signup and view all the answers

Which refrigerant has a miscibility problem with mineral oil lubricants?

R-134a Signup and view all the answers

What is a key criterion for a refrigerant to be considered environmentally safe?

It should not contribute to the destruction of the earth's ozone layer Signup and view all the answers

Why is a refrigerant's latent heat of evaporation important?

Because it changes from liquid to gas efficiently Signup and view all the answers

What do ASHRAE Standard 34 and CSA Mechanical Refrigeration Code B52 classify refrigerants based on?

Their toxicity and flammability Signup and view all the answers

In the context of refrigerants, what does toxicity refer to?

The relative poisonous characteristic of a substance Signup and view all the answers

What is a desirable property of a refrigerant in terms of its odor?

It should be detectable but non-offensive Signup and view all the answers

What is a key consideration when evaluating the environmental safety of a refrigerant?

Its impact on the earth's warming potential Signup and view all the answers

Which refrigerant needs the use of ester-based synthetic lubricants to eliminate a miscibility problem with mineral oil lubricants?

R-134a Signup and view all the answers

What is a characteristic of R-134a that distinguishes it from R-717?

Ozone depletion potential Signup and view all the answers

Why should copper and brass not be used in ammonia systems?

They corrode in the presence of ammonia Signup and view all the answers

Which refrigerant has the most widely used thermal properties in the food industry?

R-717 Signup and view all the answers

In the presence of moisture, what property of ammonia leads to corrosion of nonferrous metals like copper and brass?

Corrosive to metals Signup and view all the answers

Which of the refrigerants mentioned is the least expensive among the commonly used ones?

R-12 Signup and view all the answers

What does the numerical part of the refrigerant classification identify?

Flammability level Signup and view all the answers

What is the heat of combustion threshold for a Class 2 refrigerant?

Less than 19,000 kJ/kg Signup and view all the answers

Which refrigerant contains chlorine molecules that contribute to ozone layer depletion and global warming?

Refrigerant R-12 Signup and view all the answers

At what temperature does Refrigerant R-22 boil at atmospheric pressure?

-40.8°C Signup and view all the answers

What is a major reason for the gradual replacement of Refrigerant R-12?

Environmental impact Signup and view all the answers

Which refrigerant is non-toxic, non-flammable, and non-explosive?

Refrigerant R-12 Signup and view all the answers

What characteristic makes Refrigerant R-12 suitable for various temperature applications?

Boiling point Signup and view all the answers

What effect do refrigerants with long atmospheric life have on the environment?

Cause ozone layer depletion and global warming Signup and view all the answers

Which refrigerant group has a shorter atmospheric life than CFCs?

HCFCs Signup and view all the answers

What does the lower flammability limit (LFL) indicate about a refrigerant?

Minimum concentration for combustion Signup and view all the answers

Which refrigerant group classification poses the highest risk in terms of both toxicity and flammability?

B3 Signup and view all the answers

Which of the following is NOT a criteria for a refrigerant that contributes to its environmental safety?

Has a high heat of combustion Signup and view all the answers

Which statement about refrigerant leaks is correct, assuming all other properties are equal?

Leaks of refrigerants with detectable, but non-offensive odour are easier to detect than leaks of odourless refrigerants Signup and view all the answers

Which refrigerant property would make it suitable for use in systems that require low pressure refrigeration?

Low boiling point at atmospheric pressure Signup and view all the answers

Which refrigerant property is crucial for boosting the refrigeration cycle’s effectiveness?

High latent heat of evaporation Signup and view all the answers

Which of these refrigerant properties would be most vital when using a refrigerant near foodstuffs or other products?

Not contaminate foodstuffs or other products in the event of a system leak Signup and view all the answers

What is the primary function of the compressor in an ammonia refrigeration system?

To remove low-pressure refrigerant vapour from the evaporator and increase pressure and temperature Signup and view all the answers

What is the purpose of the Oil Separator in an ammonia refrigeration system?

To remove entrained oil from the refrigerant vapour before it enters the compressor Signup and view all the answers

What type of design is often used for single-acting reciprocating compressors?

Vertical cylinders Signup and view all the answers

What is the role of cylinder unloaders in a reciprocating compressor?

To allow the compressor to start in an unloaded condition Signup and view all the answers

What is the purpose of an oil foam breaker in a compressor?

To reduce oil foaming caused by refrigerant in the oil Signup and view all the answers

What is the principle of operation of a vane type compressor?

The vanes are forced out against the casing by centrifugal force Signup and view all the answers

What is the function of the condenser in an ammonia refrigeration system?

To cool the refrigerant vapour and cause it to condense to a liquid Signup and view all the answers

What is the role of the liquid receiver in an ammonia refrigeration system?

To store the sub-cooled liquid refrigerant before it enters the evaporator Signup and view all the answers

What is the function of the expansion valve in an ammonia refrigeration system?

To regulate the flow of liquid refrigerant into the evaporator and create a pressure drop Signup and view all the answers

What is the primary use of Refrigerant R-22 today?

In household refrigerators and low-capacity installations Signup and view all the answers

What is the primary function of the fan in the condenser?

To induce or force air up through the condenser Signup and view all the answers

What is the purpose of the liquid receiver in the refrigeration system?

To accommodate changes in the refrigerant charge and keep the condenser drained of liquid Signup and view all the answers

What type of valve is used to meter the liquid refrigerant into the evaporator?

Expansion valve Signup and view all the answers

What is the purpose of the fins in a finned tube evaporator?

To conduct heat to the tubes Signup and view all the answers

What is the function of the evaporator in the refrigeration system?

To absorb heat from the surroundings and evaporate the refrigerant Signup and view all the answers

What is the name of the type of evaporator where a continuous coil of tubing is contained between two metal plates?

Plate surface evaporator Signup and view all the answers

What is the temperature of the liquid ammonia as it enters the low-pressure section of the system?

28°C Signup and view all the answers

What is the boiling temperature of ammonia at a pressure of 135 kPa?

-15°C Signup and view all the answers

What happens to the temperature of the refrigerant vapour as it passes through the upper section of the evaporating coils?

It increases above -12°C Signup and view all the answers

What is the effect of insufficient ammonia passing through the expansion valve?

Vaporization will complete before reaching the upper section of the evaporating coils Signup and view all the answers

What is the superheat of the refrigerant vapour leaving the evaporator?

3°C Signup and view all the answers

What is the pressure of the low-pressure side of the system?

135 kPa Signup and view all the answers

What is the primary function of a condenser in a refrigeration system?

To cool the hot compressed refrigerant vapour Signup and view all the answers

What is a characteristic of rotary compressors?

Smooth flow, low vibration, and high manufacturing cost Signup and view all the answers

What type of compressor is particularly suited for refrigeration systems with a large volume of refrigerant and small to moderate pressure difference?

Centrifugal compressor Signup and view all the answers

What is the advantage of air-cooled condensers?

Simplicity and low installation costs Signup and view all the answers

What is the function of the diffuser section in a centrifugal compressor?

To convert velocity to pressure Signup and view all the answers

What is a disadvantage of centrifugal compressors?

Lower efficiency and lower pressure range Signup and view all the answers

What type of condenser uses both air and water for cooling?

Air and water-cooled (Evaporative) condenser Signup and view all the answers

What is the purpose of the gear type oil pump in a centrifugal compressor?

To provide pressure lubrication to the shaft bearings and shaft seal Signup and view all the answers

Why do centrifugal compressors require less maintenance?

Because they require external lubrication only Signup and view all the answers

What is the primary function of the liquid receiver in a refrigeration system?

To store the liquid refrigerant Signup and view all the answers

In a finned tube evaporator, what is the main function of the fins attached to the tubes?

To increase the heat transfer surface area Signup and view all the answers

What is the purpose of the needle-type expansion valve in a refrigeration system?

To create a pressure differential between high and low-pressure sides Signup and view all the answers

Where does refrigerant primarily evaporate in an evaporator in a water-cooling system?

Within the water to be cooled circulating through the tubes Signup and view all the answers

What is the distinguishing feature of a forced draft condenser compared to an induced draft condenser?

Forces air down through the condenser Signup and view all the answers

What is the function of a plate surface evaporator in a refrigeration system?

To contain a continuous coil of tubing between metal plates Signup and view all the answers

What is the purpose of the oil separator in the refrigeration system?

To remove entrained oil and prevent it from reaching the compressor Signup and view all the answers

In an ammonia refrigeration system, what is the function of the compressor?

To increase the pressure and temperature of the refrigerant Signup and view all the answers

What is the major role of the oil purifier in the refrigeration system with respect to the oil removed from the system?

Returning any ammonia in the oil to the compressor suction Signup and view all the answers

Which component in an ammonia refrigeration system is responsible for sub-cooling the refrigerant before it enters the receiver?

Condenser Signup and view all the answers

What type of refrigeration compressor is commonly used in household refrigerators?

Rotary compressor Signup and view all the answers

Which design of rotary compressor functions by trapping refrigerant between vanes and the casing, achieving compression by reducing space as the refrigerant moves?

Vane type Signup and view all the answers

What is a distinctive feature of a roller type rotary compressor in terms of roller rotation?

Always in contact with the casing Signup and view all the answers

What is the primary objective of the evaporator in a refrigeration system?

To remove heat from the surroundings Signup and view all the answers

Which component is primarily responsible for ensuring that the pressure differential is sufficient in the refrigeration system?

Compressor Signup and view all the answers

In the ammonia system, what is the purpose of the Liquid Receiver?

To store and release the liquid refrigerant Signup and view all the answers

What is the temperature of the liquid ammonia as it enters the low-pressure side of the system?

28°C Signup and view all the answers

What happens to the temperature of the vapour-liquid mixture as the 28°C liquid enters the low-pressure section?

It drops to -15°C Signup and view all the answers

Why does the refrigerant vapour become superheated as it passes through the upper section of the evaporating coils?

Because it absorbs more heat from the air Signup and view all the answers

What is the boiling temperature of ammonia at a pressure of 135 kPa?

-15°C Signup and view all the answers

What is the purpose of the refrigerant vapour absorbing heat from the air surrounding the coils in the evaporator?

To decrease the temperature of the air Signup and view all the answers

What is the superheat of the refrigerant vapour leaving the evaporator?

3°C Signup and view all the answers

In a rotary compressor, what is the purpose of the spring-loaded blade?

To separate the suction and discharge openings Signup and view all the answers

What is the main advantage of centrifugal compressors?

Less maintenance and smooth operation Signup and view all the answers

What type of condenser uses both air and water for cooling?

Evaporative condenser Signup and view all the answers

What is the purpose of the diffuser section in a centrifugal compressor?

To convert velocity into pressure Signup and view all the answers

Why are rotary compressors expensive to manufacture?

Due to the precision machining required Signup and view all the answers

What is the purpose of the fan in an evaporative condenser?

To increase the air flow Signup and view all the answers

What is a disadvantage of centrifugal compressors?

Lower efficiency and pressure range Signup and view all the answers

What is the purpose of the gear type oil pump in a centrifugal compressor?

To lubricate the shaft bearings and shaft seal Signup and view all the answers

What type of compressor is suitable for refrigeration systems with a large volume of refrigerant and small to moderate pressure difference?

Centrifugal compressor Signup and view all the answers

What absorbs heat in the evaporator of a refrigeration system?

Chilled water Signup and view all the answers

What maintains a constant level of liquid refrigerant in the evaporator of a refrigeration system?

Evaporator float valve Signup and view all the answers

Where does the resulting refrigerant liquid collect after condensing in a refrigeration system?

Sump at the bottom of the condenser Signup and view all the answers

What is the purpose of the crossover pipe in a centrifugal compression system?

Connect the first stage to the second stage Signup and view all the answers

What is the term used for the phase change process in which refrigerant gas becomes liquid in a condenser?

Condensation Signup and view all the answers

Which component of the refrigeration system is responsible for withdrawing the vaporized refrigerant from the evaporator?

Compressor Signup and view all the answers

What is a characteristic of a direct refrigeration system?

The evaporator is in direct contact with the material being cooled Signup and view all the answers

What is the function of the brine in an indirect refrigeration system?

To absorb heat from the refrigerated space Signup and view all the answers

What is the typical temperature to which the brine is cooled in a skating rink application?

-11°C Signup and view all the answers

What is a common type of brine used in indirect refrigeration systems?

All of the above Signup and view all the answers

In an air conditioning system, what is commonly used as the brine in indirect refrigeration?

Water Signup and view all the answers

What is the purpose of the evaporator coils in an indirect refrigeration system?

To absorb heat from the brine Signup and view all the answers

Which type of compressor is used in the air conditioning system described in the text?

Centrifugal compressor Signup and view all the answers

What process occurs in the condenser of the air conditioning system described in the text?

The refrigerant gas is condensed Signup and view all the answers

What is the role of the evaporator float valve in the described air conditioning system?

To maintain a constant level of liquid refrigerant in the evaporator Signup and view all the answers

What happens to the refrigerant once it leaves the evaporator in the described air conditioning system?

It is sent to the compressor for further compression Signup and view all the answers

What is the primary use of the chilled water in the described air conditioning system?

To decrease the temperature of the air used for the building air conditioning Signup and view all the answers

How many stages does the centrifugal compressor used in the described air conditioning system have?

Two stages Signup and view all the answers

What is the primary objective of using a brine solution in indirect refrigeration systems?

To cool the material or space being refrigerated Signup and view all the answers

What is the typical operating temperature of the brine solution in a skating rink application?

-11°C Signup and view all the answers

What is the purpose of the evaporator coils in an indirect refrigeration system?

To cool the brine solution Signup and view all the answers

Which of the following is NOT a type of brine solution used in indirect refrigeration systems?

Refrigerant R-12 Signup and view all the answers

What is the primary advantage of using an indirect refrigeration system over a direct system?

Greater flexibility in system design Signup and view all the answers

In an air conditioning system, what is commonly used as the brine in indirect refrigeration?

Water Signup and view all the answers

What is the purpose of the economizer in the given refrigeration system?

To cool high-pressure liquid before it enters the evaporator Signup and view all the answers

What happens to superheated vapour leaving the low-pressure cylinder?

It mixes with high-pressure saturated liquid before entering the intercooler Signup and view all the answers

What is the purpose of the connection from the top of the still to the low-pressure suction?

To allow any liquid refrigerant that drains into this receiver with the oil to boil off Signup and view all the answers

What is a common misconception about two-stage reciprocating compressors?

They are not common in service Signup and view all the answers

What type of compressor has largely replaced two-stage reciprocating compressors?

Rotary compressors Signup and view all the answers

What is the function of the intercooler in the given refrigeration system?

To cool refrigerant vapour and allow liquid to drain off Signup and view all the answers

How does the duplex compressor in the indirect refrigeration system facilitate low temperature operation?

By accomplishing two-stage compression, lowering the discharge temperature Signup and view all the answers

What is the role of the liquid cooler in the indirect refrigeration system?

To allow the liquid in the shell to evaporate, cooling the high-pressure liquid that goes to the evaporator Signup and view all the answers

How does the connection from the top of the still to the low-pressure suction contribute to the performance of the indirect refrigeration system?

By allowing any liquid refrigerant that drains into this receiver with the oil to boil off Signup and view all the answers

What is the primary reason two-stage reciprocating compressors have been largely replaced by rotary compressors?

Rotary compressors are more compact and have fewer moving parts Signup and view all the answers

What is the purpose of the intercooler in the indirect refrigeration system?

To allow the superheated vapor to mix with high-pressure saturated liquid and absorb the superheat Signup and view all the answers

How does the drain system in the indirect refrigeration system contribute to the overall efficiency of the system?

By directing the drains from separators, traps, and coils to a central oil-recovery drum and still Signup and view all the answers

What is the function of the rotary compressor in a two-stage refrigeration system?

Serving as a booster compressor Signup and view all the answers

Why is an intercooler used in a two-stage refrigeration system?

To provide a chilling effect for the refrigerant Signup and view all the answers

What is the role of the liquid and gas cooler in a two-stage refrigeration system?

Vaporizing the liquid refrigerant Signup and view all the answers

What happens to the pressurized vapour after leaving the condenser in a two-stage refrigeration system?

It returns to the evaporator of the low-temperature room Signup and view all the answers

What is the purpose of the oil separator in a two-stage refrigeration system?

Releasing excess oil back into the compressor Signup and view all the answers

In a two-stage refrigeration system, why does the low-pressure side require a large volume handling capacity?

To accommodate the low-density vapour Signup and view all the answers

What is the purpose of a booster compressor in a multi-stage refrigeration plant?

To increase the pressure of low-density vapour. Signup and view all the answers

What is the name of the part that receives the cooled and condensed refrigerant before it is used in a refrigeration system?

Liquid receiver Signup and view all the answers

Which component in the refrigeration system is responsible for removing oil from the discharged vapour before it enters the condenser?

Oil separator Signup and view all the answers

What is the function of the intercooler in a multi-stage refrigeration system?

To cool the intermediate pressure vapour before entering the condenser Signup and view all the answers

In which stage of the refrigeration system does the vapour from the low-temperature evaporator enter the 1st stage compressor?

1st stage compressor Signup and view all the answers

What happens to the volume of a kilogram of vapour from the evaporator as it transitions through the refrigeration system?

It increases Signup and view all the answers

What is the purpose of a water-cooled intercooler in a multi-stage refrigeration system?

To remove heat from the discharge of the low-pressure compressor before entering the high-pressure compressor Signup and view all the answers

Why is the compression divided between two single-stage compressors in the described refrigeration system?

Due to the greater range between suction and discharge pressures Signup and view all the answers

How does the water-cooled intercooler impact the high-pressure compressor in the multi-stage refrigeration system?

Reduces the temperature of the liquid refrigerant entering the high-pressure compressor Signup and view all the answers

What is the role of the regulator or expansion valve in a compression refrigeration system?

To control the flow of refrigerant into the evaporator Signup and view all the answers

How does the water-cooled intercooler help before the refrigeration system enters the high-pressure compressor?

Decreases the temperature of the refrigerant Signup and view all the answers

What is the purpose of a water-cooled intercooler in a multi-stage refrigeration system?

To remove heat from the refrigerant vapour between stages Signup and view all the answers

What effect does the water-cooled intercooler have on the size and power consumption of the high-pressure compressor in a multi-stage refrigeration system?

Decreases the size and power consumption Signup and view all the answers

How does the water-cooled intercooler contribute to the overall efficiency of a multi-stage refrigeration system?

By removing heat from the refrigerant vapour Signup and view all the answers

In a multi-stage refrigeration system, what is the function of the water-cooled intercooler with regards to the refrigerant vapour?

Removes heat from the refrigerant vapour Signup and view all the answers

How does the water-cooled intercooler impact the performance of the high-pressure compressor in a multi-stage refrigeration system?

Decreases the power consumption of the high-pressure compressor Signup and view all the answers

How does the water-cooled intercooler reduce the size and power consumption of the high-pressure compressor in a multi-stage refrigeration system?

By decreasing the temperature of the vapour Signup and view all the answers

What is the main disadvantage of using ammonia as a refrigerant in a multi-stage refrigeration system?

It is highly toxic Signup and view all the answers

How does the use of two single-stage compressors in a multi-stage refrigeration system impact the overall efficiency of the system compared to a single two-stage compressor?

It increases the overall efficiency Signup and view all the answers

What is the primary function of the fan in the condenser in a refrigeration system?

To cool the refrigerant Signup and view all the answers

Which type of compressor is commonly used in household refrigerators?

Rotary compressor Signup and view all the answers

What is the primary purpose of the analyzer in an ammonia absorption refrigeration system?

To separate ammonia vapour from water vapour Signup and view all the answers

What is the role of the rectifier in an ammonia absorption refrigeration system?

To cool the ammonia vapour further Signup and view all the answers

What happens to the ammonia as it passes through the control or expansion valve?

Its pressure is reduced Signup and view all the answers

What is the purpose of the heat exchanger in the ammonia absorption refrigeration system?

To exchange heat between the strong liquor and the generator Signup and view all the answers

What is the role of the generator in an ammonia absorption refrigeration system?

To heat the strong liquor Signup and view all the answers

What is the temperature at which the ammonia boils in the evaporator?

-15°C Signup and view all the answers

What is the primary purpose of the analyzer in the ammonia absorption refrigeration system?

To separate water vapour from ammonia vapour Signup and view all the answers

3B2 E2.5 C10 Review

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Questions and Answers

Which class of refrigerants is non-toxic and non-flammable?

What is the heat of combustion threshold that classifies a refrigerant as a Class 2 refrigerant?

Which refrigerant is a member of the HCFC group and is highly stable?

At what temperature does Refrigerant R-12 boil at atmospheric pressure?

What is a property that makes Refrigerant R-12 suitable for various temperature applications?

What effect does R-12 have on the earth's ozone layer and greenhouse effect?

Which refrigerant has been widely used in automotive air conditioning systems?

What is the primary use of Refrigerant R-22 today?

Which category of refrigerants has a higher flammability limit than 0.10 kg/m3?

What could be a reason that synthetic oils are used with R-22?

Which refrigerant is being used to replace R-12 in automotive air conditioning systems?

Which refrigerant is the only one outside of the fluorocarbon group that is used to a great extent?

Which refrigerant has a boiling point of -33.3°C at atmospheric pressure?

Which refrigerant is non-flammable and non-explosive?

Which refrigerant is not miscible in oil and does not dilute the oil in the compressor crankcase?

Which refrigerant has a miscibility problem with mineral oil lubricants?

What is a key criterion for a refrigerant to be considered environmentally safe?

Why is a refrigerant's latent heat of evaporation important?

What do ASHRAE Standard 34 and CSA Mechanical Refrigeration Code B52 classify refrigerants based on?

In the context of refrigerants, what does toxicity refer to?

What is a desirable property of a refrigerant in terms of its odor?

What is a key consideration when evaluating the environmental safety of a refrigerant?

Which refrigerant needs the use of ester-based synthetic lubricants to eliminate a miscibility problem with mineral oil lubricants?

What is a characteristic of R-134a that distinguishes it from R-717?

Why should copper and brass not be used in ammonia systems?

Which refrigerant has the most widely used thermal properties in the food industry?

In the presence of moisture, what property of ammonia leads to corrosion of nonferrous metals like copper and brass?

Which of the refrigerants mentioned is the least expensive among the commonly used ones?

What does the numerical part of the refrigerant classification identify?

What is the heat of combustion threshold for a Class 2 refrigerant?

Which refrigerant contains chlorine molecules that contribute to ozone layer depletion and global warming?

At what temperature does Refrigerant R-22 boil at atmospheric pressure?

What is a major reason for the gradual replacement of Refrigerant R-12?

Which refrigerant is non-toxic, non-flammable, and non-explosive?

What characteristic makes Refrigerant R-12 suitable for various temperature applications?

What effect do refrigerants with long atmospheric life have on the environment?

Which refrigerant group has a shorter atmospheric life than CFCs?

What does the lower flammability limit (LFL) indicate about a refrigerant?

Which refrigerant group classification poses the highest risk in terms of both toxicity and flammability?

Which of the following is NOT a criteria for a refrigerant that contributes to its environmental safety?

Which statement about refrigerant leaks is correct, assuming all other properties are equal?

Which refrigerant property would make it suitable for use in systems that require low pressure refrigeration?

Which refrigerant property is crucial for boosting the refrigeration cycle’s effectiveness?

Which of these refrigerant properties would be most vital when using a refrigerant near foodstuffs or other products?

What is the primary function of the compressor in an ammonia refrigeration system?

What is the purpose of the Oil Separator in an ammonia refrigeration system?

What type of design is often used for single-acting reciprocating compressors?

What is the role of cylinder unloaders in a reciprocating compressor?

What is the purpose of an oil foam breaker in a compressor?

What is the principle of operation of a vane type compressor?

What is the function of the condenser in an ammonia refrigeration system?

What is the role of the liquid receiver in an ammonia refrigeration system?

What is the function of the expansion valve in an ammonia refrigeration system?

What is the primary use of Refrigerant R-22 today?

What is the primary function of the fan in the condenser?

What is the purpose of the liquid receiver in the refrigeration system?

What type of valve is used to meter the liquid refrigerant into the evaporator?

What is the purpose of the fins in a finned tube evaporator?

What is the function of the evaporator in the refrigeration system?

What is the name of the type of evaporator where a continuous coil of tubing is contained between two metal plates?

What is the temperature of the liquid ammonia as it enters the low-pressure section of the system?

What is the boiling temperature of ammonia at a pressure of 135 kPa?

What happens to the temperature of the refrigerant vapour as it passes through the upper section of the evaporating coils?

What is the effect of insufficient ammonia passing through the expansion valve?

What is the superheat of the refrigerant vapour leaving the evaporator?

What is the pressure of the low-pressure side of the system?

What is the primary function of a condenser in a refrigeration system?

What is a characteristic of rotary compressors?

What type of compressor is particularly suited for refrigeration systems with a large volume of refrigerant and small to moderate pressure difference?

What is the advantage of air-cooled condensers?

What is the function of the diffuser section in a centrifugal compressor?

What is a disadvantage of centrifugal compressors?

What type of condenser uses both air and water for cooling?

What is the purpose of the gear type oil pump in a centrifugal compressor?

Why do centrifugal compressors require less maintenance?

What is the primary function of the liquid receiver in a refrigeration system?

In a finned tube evaporator, what is the main function of the fins attached to the tubes?