Industrial Refrigeration Exam Questions
with Correct Answers
As defined in chapter 1 of this text the primary purpose of refrigeration system is -
Answer-To maintain a temperature
Operators must keep refrigeration systems operating safely and efficiently. Which of the
following best describes the areas of required knowledge for this to be possible. -
Answer-Basic physical principles, Inter-preparation of information from temperature and
pressure gauges. Basic operating principles.
Mechanical refrigeration is a series of steps that - Answer-moves heat energy from the
space or object to an area where It can do no harm.
Heat energy always flows - Answer-From an object at a higher temperature to an object
at a lower temperature
sensible heat - Answer-Is heat energy that causes a change in temperature but does
not cause a change of state
Latent heat - Answer-Is heat energy that causes a change of state but does not cause a
change in temperature
Which of the answers below is an example of heat transfer by convection - Answer-
Warm air moving over an object
How does the refrigeration technician/operator know what the conditions are within the
refrigeration system - Answer-By using his knowledge of system basic operating
principles to evaluate temperature and pressure readings
How was cooling accomplished by mechanical refrigeration system - Answer-By
removing heat energy from one object or area
Which of the following is used to measure the quality of heat energy - Answer-British
thermal units BTUs or calories.
Which of the following are used in heat calculations - Answer-Mass, latent heat,
temperature, specific heat.
Latent heat of vaporization - Answer-Is the heat energy required to cause a liquid to
become a vapor
Pressure is A measure of - Answer-The relationship of a force being applied over a
given area
,The relationship between temperature difference in heat flow is - Answer-The greater
the temperature difference the more rapid the heat flows
Specific heat - Answer-Is greater as a substance requires more heat energy to increase
temperature
Temperature is a measure of - Answer-The intensity of heat energy in an object
Which of the answers below is an example of heat transferred by conduction - Answer-
A rod heated on one end and becoming warm at the other end.
Which are the two most common forms of heat transfer in refrigeration - Answer-
Conduction and convection
The condition of a boiling liquid is - Answer-Saturated
A vapor cannot be - Answer-Subcooled
What kind of measure is a ton of refrigeration - Answer-A rate of heat transferred in
BTUs per unit of time
The condition of a liquid that exist at a temperature below its boiling point is - Answer-
Sub cooled
Which does the refrigerant in the condenser change State from vapor to a liquid -
Answer-The refrigerant loses heat energy to the sub rounding environment
The expansion valve controls only one of its items below which is it - Answer-The flow
of liquid into the evaporator
Flash gas is - Answer-Only the gas created at the expansion device
Which is a example of pressure drop - Answer-The loss of pressure as a fluid moves
down the pipe due to the interaction of the fluid in the inner walls of the pipe
Refrigerant absorbs the most heat when - Answer-Changing from a liquid to a vapor
The latent heat of condensation of a substance is exactly the same quality as - Answer-
The latent heat of evaporation of the substance
Saturated conditions exist - Answer-At some point within an evaporator and condenser
Flash gas - Answer-Is formed after the point of expansion
, The four necessary components of a mechanical refrigeration system are - Answer-
Expansion device, evaporator, compressor, condenser
A conventional mechanical refrigeration system is considered - Answer-A closed loop
system
Super heat is found at which point of a typical system - Answer-The compressor suction
and compressor discharge line
In an operating ammonia refrigeration system, subcooled refrigerant can only be a -
Answer-Liquid
Superheated refrigerant can only be a - Answer-Vapor
Saturated refrigerant can - Answer-Be a liquid, vapor or a combination of the two
What is needed to get a fluid to flow - Answer-A pressure difference
What is one advantage to having evaporator pressures higher than atmospheric
pressure - Answer-Higher pressures keep air out of the system
R 507 is a/an - Answer-Azeotrope
what do you multiply times the mass flow rate to determine the vapor flow rate through
the compressor - Answer-Specific volume cubic feet/lb
Three factors to consider when choosing a refrigerant - Answer-Cost, availability, and
safety
According to this text, trapped ammonia liquid results and how much pressure change?
- Answer-100 to 150 PSI per degree Fahrenheit increase
One positive characteristic of halocarbon refrigerants is - Answer-They are usually not
explosive
A slight leak in a fitting on a HCFC/22 system causes the Halide torch flame to -
Answer-Turn green
If the reciprocating Systems evaporator temperature is decreased, what happens to the
compressor theoretical discharge temperature? - Answer-Discharge temperature rises
Which refrigerant requires the largest compressor displacement per ton? - Answer-R-
134a
Which is not a direct symptom of air in an ammonia system - Answer-Decreased
evaporating temperature
with Correct Answers
As defined in chapter 1 of this text the primary purpose of refrigeration system is -
Answer-To maintain a temperature
Operators must keep refrigeration systems operating safely and efficiently. Which of the
following best describes the areas of required knowledge for this to be possible. -
Answer-Basic physical principles, Inter-preparation of information from temperature and
pressure gauges. Basic operating principles.
Mechanical refrigeration is a series of steps that - Answer-moves heat energy from the
space or object to an area where It can do no harm.
Heat energy always flows - Answer-From an object at a higher temperature to an object
at a lower temperature
sensible heat - Answer-Is heat energy that causes a change in temperature but does
not cause a change of state
Latent heat - Answer-Is heat energy that causes a change of state but does not cause a
change in temperature
Which of the answers below is an example of heat transfer by convection - Answer-
Warm air moving over an object
How does the refrigeration technician/operator know what the conditions are within the
refrigeration system - Answer-By using his knowledge of system basic operating
principles to evaluate temperature and pressure readings
How was cooling accomplished by mechanical refrigeration system - Answer-By
removing heat energy from one object or area
Which of the following is used to measure the quality of heat energy - Answer-British
thermal units BTUs or calories.
Which of the following are used in heat calculations - Answer-Mass, latent heat,
temperature, specific heat.
Latent heat of vaporization - Answer-Is the heat energy required to cause a liquid to
become a vapor
Pressure is A measure of - Answer-The relationship of a force being applied over a
given area
,The relationship between temperature difference in heat flow is - Answer-The greater
the temperature difference the more rapid the heat flows
Specific heat - Answer-Is greater as a substance requires more heat energy to increase
temperature
Temperature is a measure of - Answer-The intensity of heat energy in an object
Which of the answers below is an example of heat transferred by conduction - Answer-
A rod heated on one end and becoming warm at the other end.
Which are the two most common forms of heat transfer in refrigeration - Answer-
Conduction and convection
The condition of a boiling liquid is - Answer-Saturated
A vapor cannot be - Answer-Subcooled
What kind of measure is a ton of refrigeration - Answer-A rate of heat transferred in
BTUs per unit of time
The condition of a liquid that exist at a temperature below its boiling point is - Answer-
Sub cooled
Which does the refrigerant in the condenser change State from vapor to a liquid -
Answer-The refrigerant loses heat energy to the sub rounding environment
The expansion valve controls only one of its items below which is it - Answer-The flow
of liquid into the evaporator
Flash gas is - Answer-Only the gas created at the expansion device
Which is a example of pressure drop - Answer-The loss of pressure as a fluid moves
down the pipe due to the interaction of the fluid in the inner walls of the pipe
Refrigerant absorbs the most heat when - Answer-Changing from a liquid to a vapor
The latent heat of condensation of a substance is exactly the same quality as - Answer-
The latent heat of evaporation of the substance
Saturated conditions exist - Answer-At some point within an evaporator and condenser
Flash gas - Answer-Is formed after the point of expansion
, The four necessary components of a mechanical refrigeration system are - Answer-
Expansion device, evaporator, compressor, condenser
A conventional mechanical refrigeration system is considered - Answer-A closed loop
system
Super heat is found at which point of a typical system - Answer-The compressor suction
and compressor discharge line
In an operating ammonia refrigeration system, subcooled refrigerant can only be a -
Answer-Liquid
Superheated refrigerant can only be a - Answer-Vapor
Saturated refrigerant can - Answer-Be a liquid, vapor or a combination of the two
What is needed to get a fluid to flow - Answer-A pressure difference
What is one advantage to having evaporator pressures higher than atmospheric
pressure - Answer-Higher pressures keep air out of the system
R 507 is a/an - Answer-Azeotrope
what do you multiply times the mass flow rate to determine the vapor flow rate through
the compressor - Answer-Specific volume cubic feet/lb
Three factors to consider when choosing a refrigerant - Answer-Cost, availability, and
safety
According to this text, trapped ammonia liquid results and how much pressure change?
- Answer-100 to 150 PSI per degree Fahrenheit increase
One positive characteristic of halocarbon refrigerants is - Answer-They are usually not
explosive
A slight leak in a fitting on a HCFC/22 system causes the Halide torch flame to -
Answer-Turn green
If the reciprocating Systems evaporator temperature is decreased, what happens to the
compressor theoretical discharge temperature? - Answer-Discharge temperature rises
Which refrigerant requires the largest compressor displacement per ton? - Answer-R-
134a
Which is not a direct symptom of air in an ammonia system - Answer-Decreased
evaporating temperature
