RETA Industrial Refrigeration Book
2 Exam 2026 Questions and Answers
Which of the following factors listed below does not affect heat transfer?
(pg. 1-2)
A) Temperature Difference
B) Surface Area
C) Thermal Conductivity
D) Density - Correct answer-D) Density
An example of a poor conductor of heat is? (pg. 1-3)
A) Aluminum Tubing
B) Schedule 40 Steel Pipe
C) Wood
D) Water - Correct answer-C) Wood
Thermal conductivity ('K') is? (pg. 1-3)
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,A) Exactly the same for any metal
B) The number of BTU's that will pass in 1 hour through a material 1" thick with
an area of 1 sq. ft. if the temperature difference from one side to the other is 1°F
C) A measure of the total energy (heat content) per pound of refrigerant measured
in BTU's
D) A relationship between heat and temperature that is useful in determining
discharge temperatures. It is heat moved into or out of the process, divided by the
absolute temperature in BTU's/pound/R - Correct answer-B) The number of BTU's
that will pass in 1 hour through a material 1" thick with an area of 1 sq. ft. if the
temperature difference from one side to the other is 1°F
Which is NOT a common source of fouling of a heat exchange surface?
(pg. 1-7)
A) Water
B) Oil
C) Frost
D) Dirt - Correct answer-A) Water
Which statement is true? (pg. 1-3)
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,A) The higher the 'k' factor, the greater the thermal conductivity
B) The lower the 'k' factor, the greater the thermal conductivity
C) The higher the 'k' factor, the lower the thermal conductivity
D) The 'k' factor is not associated with thermal conductivity - Correct answer-A)
The higher the 'k' factor, the greater the thermal conductivity
Optimum 'U' factor for the given material that the heat exchanger is made of results
when? (pg. 1-7/8)
A) There is no impeding substance such as ice, dirt, or oil on the surfaces of the
heat exchanger tubes
B) Maximum airflow across the evaporator is achieved
C) The system is operating with the design recirculation low
D) The system is maintaining temperature - Correct answer-A) There is no
impeding substance such as ice, dirt, or oil on the surfaces of the heat exchanger
tubes
When air flow is decreased across a heat exchange surface, cooling capacity is?
(pg. 1-10)
A) Reduced
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, B) Increased
C) Not changed because area is not changed
D) Not changed because evaporator temperature is not changed - Correct answer-
A) Reduced
Centrifugal fans have an advantage over propeller fans in that they
______________ than prop fans? (pg. 1-12)
A) Require less physical space
B) Consume more hp per CFM of air moved
C) Are quieter
D) Have fewer components to maintain - Correct answer-C) Are quieter
The operating engineer? (pg. 1-7)
A) Cannot change the 'k' factor of the metal but has some control of the overall 'U'
factor for the evaporator as a unit
B) Can increase 'k' factor by increasing the air velocity over the evaporator and has
some control of the overall 'U' factor for the evaporator as a unit
C) Should allow frost to collect on the evaporator increase 'k' factor
©COPYRIGHT 2025, ALL RIGHTS RESERVED 4
2 Exam 2026 Questions and Answers
Which of the following factors listed below does not affect heat transfer?
(pg. 1-2)
A) Temperature Difference
B) Surface Area
C) Thermal Conductivity
D) Density - Correct answer-D) Density
An example of a poor conductor of heat is? (pg. 1-3)
A) Aluminum Tubing
B) Schedule 40 Steel Pipe
C) Wood
D) Water - Correct answer-C) Wood
Thermal conductivity ('K') is? (pg. 1-3)
©COPYRIGHT 2025, ALL RIGHTS RESERVED 1
,A) Exactly the same for any metal
B) The number of BTU's that will pass in 1 hour through a material 1" thick with
an area of 1 sq. ft. if the temperature difference from one side to the other is 1°F
C) A measure of the total energy (heat content) per pound of refrigerant measured
in BTU's
D) A relationship between heat and temperature that is useful in determining
discharge temperatures. It is heat moved into or out of the process, divided by the
absolute temperature in BTU's/pound/R - Correct answer-B) The number of BTU's
that will pass in 1 hour through a material 1" thick with an area of 1 sq. ft. if the
temperature difference from one side to the other is 1°F
Which is NOT a common source of fouling of a heat exchange surface?
(pg. 1-7)
A) Water
B) Oil
C) Frost
D) Dirt - Correct answer-A) Water
Which statement is true? (pg. 1-3)
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
,A) The higher the 'k' factor, the greater the thermal conductivity
B) The lower the 'k' factor, the greater the thermal conductivity
C) The higher the 'k' factor, the lower the thermal conductivity
D) The 'k' factor is not associated with thermal conductivity - Correct answer-A)
The higher the 'k' factor, the greater the thermal conductivity
Optimum 'U' factor for the given material that the heat exchanger is made of results
when? (pg. 1-7/8)
A) There is no impeding substance such as ice, dirt, or oil on the surfaces of the
heat exchanger tubes
B) Maximum airflow across the evaporator is achieved
C) The system is operating with the design recirculation low
D) The system is maintaining temperature - Correct answer-A) There is no
impeding substance such as ice, dirt, or oil on the surfaces of the heat exchanger
tubes
When air flow is decreased across a heat exchange surface, cooling capacity is?
(pg. 1-10)
A) Reduced
©COPYRIGHT 2025, ALL RIGHTS RESERVED 3
, B) Increased
C) Not changed because area is not changed
D) Not changed because evaporator temperature is not changed - Correct answer-
A) Reduced
Centrifugal fans have an advantage over propeller fans in that they
______________ than prop fans? (pg. 1-12)
A) Require less physical space
B) Consume more hp per CFM of air moved
C) Are quieter
D) Have fewer components to maintain - Correct answer-C) Are quieter
The operating engineer? (pg. 1-7)
A) Cannot change the 'k' factor of the metal but has some control of the overall 'U'
factor for the evaporator as a unit
B) Can increase 'k' factor by increasing the air velocity over the evaporator and has
some control of the overall 'U' factor for the evaporator as a unit
C) Should allow frost to collect on the evaporator increase 'k' factor
©COPYRIGHT 2025, ALL RIGHTS RESERVED 4
