Reta Caro Exam Practice Test
1. Conduction is defined as heat energy that is: moving through a solid substance
2. What is the primary purpose of a refrigeration system ?: achieve and maintain a
temperature
3. What is a hazard of trapping liquid ?: A possible release
4. How much can the pressure of trapped liquid increase per degree Fahrenheit of
temperature increase: 100 to 150 psi
5. Mechanical refrigeration is a series of steps that: moves heat energy from a space or
object to an area where it can do no harm
6. How does the refrigeration compressor maintain the temperature in the
system evaporators ?: Drawing out vaporized refrigerant at a rate to maintain the desired
evaporating pressure
7. Which natural refrigerant is considered to be non- flammable: Carbon Dioxide
8. Heat energy always flows: from an object at a higher temperature to an object at a
lower temperature
9. 32 psia equals: 17.3 psig
10. 0 ° F is equal to: -18 ° C
11. Why does the refrigerant in the condenser change state from vapor to liquid: The
refrigerant loses heat energy to the surrounding environment
12. If a liquid is below its saturation temperature what is its condition ?: Subcooled
13. What are the four necessary components of a mechanical refrigeration system ?:
expansion device , evaporator , compressor , condenser
14. Superheat is found at which points of a typical system ?: The compressor suction
and compressor discharge line
15. What are the replacement blended refrigerants called ?: An azeotrope or zeotrope
16. What is one positive characteristic of halocarbon refrigerants ?: They are usually not
flammable
17. What is the primary reason for concern about HCFC- 22 concentration in an engine
room ?: Oxygen deprivation
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, .
18. O psig is equal to: 14.7 psia
19. Discharge vapor from all compressors: will contain some level of superheat
20. Which category of compressor " traps " a volume of refrigerant vapor prior to
compression ?: Positive displacement
21. When suction pressure rises , the operator should: start another compressor
22 The crankcase oil heater should be ON: when the compressor is off .
23. Slugging is caused by: oil or liquid refrigerant
24. What should be done if liquid refrigerant appears while draining oil ?: Do what the
SOP states
25. Proper oil management for a refrigeration system requires that: a log should
record all oil added to and removed from a system
26. When heat is added to saturated liquid refrigerant it will always: evaporate 27.
What effect does the addition of fins to evaporator coils have ?: It increases the
efficiency of a unit by increasing the surface area
28. During hot gas defrost: high pressure gas flows through and condenses in the
evaporator
29. Evaporative condensers: derive their heat rejection capability from the evaporation
of water
30. Air cooled condensers usually have: higher head pressures than evaporative
condensers
31. What are the two types high pressure receivers based on how liquid flows
into them ?: Surge and through type
32. It is good practice to only fill a vessel how full with liquid ?: 80 %
33. Bottling is defined as: refrigerant held in the condenser due to the pressure
difference at the outlet of the condenser caused by active and inactive condenser
circuits
34. What is a non condensable gas in a refrigeration system ?: A gas that cannot be
condensed at the temperatures and pressures in the system
35. In refrigeration , what does purging refer to ?: Removing non condensables from
the system
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1. Conduction is defined as heat energy that is: moving through a solid substance
2. What is the primary purpose of a refrigeration system ?: achieve and maintain a
temperature
3. What is a hazard of trapping liquid ?: A possible release
4. How much can the pressure of trapped liquid increase per degree Fahrenheit of
temperature increase: 100 to 150 psi
5. Mechanical refrigeration is a series of steps that: moves heat energy from a space or
object to an area where it can do no harm
6. How does the refrigeration compressor maintain the temperature in the
system evaporators ?: Drawing out vaporized refrigerant at a rate to maintain the desired
evaporating pressure
7. Which natural refrigerant is considered to be non- flammable: Carbon Dioxide
8. Heat energy always flows: from an object at a higher temperature to an object at a
lower temperature
9. 32 psia equals: 17.3 psig
10. 0 ° F is equal to: -18 ° C
11. Why does the refrigerant in the condenser change state from vapor to liquid: The
refrigerant loses heat energy to the surrounding environment
12. If a liquid is below its saturation temperature what is its condition ?: Subcooled
13. What are the four necessary components of a mechanical refrigeration system ?:
expansion device , evaporator , compressor , condenser
14. Superheat is found at which points of a typical system ?: The compressor suction
and compressor discharge line
15. What are the replacement blended refrigerants called ?: An azeotrope or zeotrope
16. What is one positive characteristic of halocarbon refrigerants ?: They are usually not
flammable
17. What is the primary reason for concern about HCFC- 22 concentration in an engine
room ?: Oxygen deprivation
1/6
, .
18. O psig is equal to: 14.7 psia
19. Discharge vapor from all compressors: will contain some level of superheat
20. Which category of compressor " traps " a volume of refrigerant vapor prior to
compression ?: Positive displacement
21. When suction pressure rises , the operator should: start another compressor
22 The crankcase oil heater should be ON: when the compressor is off .
23. Slugging is caused by: oil or liquid refrigerant
24. What should be done if liquid refrigerant appears while draining oil ?: Do what the
SOP states
25. Proper oil management for a refrigeration system requires that: a log should
record all oil added to and removed from a system
26. When heat is added to saturated liquid refrigerant it will always: evaporate 27.
What effect does the addition of fins to evaporator coils have ?: It increases the
efficiency of a unit by increasing the surface area
28. During hot gas defrost: high pressure gas flows through and condenses in the
evaporator
29. Evaporative condensers: derive their heat rejection capability from the evaporation
of water
30. Air cooled condensers usually have: higher head pressures than evaporative
condensers
31. What are the two types high pressure receivers based on how liquid flows
into them ?: Surge and through type
32. It is good practice to only fill a vessel how full with liquid ?: 80 %
33. Bottling is defined as: refrigerant held in the condenser due to the pressure
difference at the outlet of the condenser caused by active and inactive condenser
circuits
34. What is a non condensable gas in a refrigeration system ?: A gas that cannot be
condensed at the temperatures and pressures in the system
35. In refrigeration , what does purging refer to ?: Removing non condensables from
the system
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