COMMERCIAL REFRIGERATION
NEWEST STUDY GUIDE||UPDATED
2026/2027 SYLLABUS EXAM
QUESTIONS AND CORRECT
SOLUTIONS||A+ GRADED
Unit Topic Focus Question Numbers
Unit
Refrigerants and System Fundamentals 1 - 18
1
Unit
Compressors and Oil Management 19 - 33
2
Unit
Condensers, Receivers, and Head Pressure Control 34 - 46
3
Unit
Metering Devices and Evaporators 47 - 68
4
Unit
System Accessories and Piping 69 - 82
5
Unit
Electrical Controls and Troubleshooting 83 - 107
6
Unit
System Applications and Special Topics 108 - 118
7
,Unit 1: Refrigerants and System Fundamentals
1. The ______ is the first component of a refrigeration system that must be
determined since its chemical and physical properties play a large role in selecting
the other components.
ANSWER: Refrigerant
2. Anything that can boil at a _____ temperature and condense at a _____
temperature can be used as a refrigerant.
ANSWER: boil at a high temperature; condense at a low temperature
3. Water could be used as a refrigerant if the pressure was adequately _____.
ANSWER: low (For example, it boils at 40°F if in a vacuum of 29.75 in Hg)
4. Refrigerants that utilize a change in latent heat are much more ______ than ones
that utilize a change in sensible heat.
ANSWER: efficient
5. The refrigerant's temperature is controlled by its _____.
ANSWER: pressure
6. PT charts are:
ANSWER: Pressure temperature charts. They correlate the saturation temperature and
pressure of commonly used refrigerants.
7. An indication of non-condensable gas in a refrigeration system is significantly:
a. Lower-than-normal suction pressures.
b. higher-than-normal suction pressures.
c. Lower-than-normal head pressures.
d. higher-than-normal head pressures.
ANSWER: D
8. What is the correct gauge pressure corresponding to an absolute pressure of
24.7 psia at sea level?
a. 10 psig.
b. 12.6 psig.
c. 39.4 psig.
d. 39.7 psig.
ANSWER: A
9. Refrigerants can be divided into five major chemical categories based on their
chemical composition. Name three of them.
, ANSWER: Hydrocarbons (HC), Chlorofluorocarbons (CFC), Hydrofluorocarbons (HFC),
Hydrochlorofluorocarbons (HCFC), Natural refrigerants (CO2, NH3).
10. CFCs (Chlorofluorocarbons) are ____ halogenated refrigerants.
ANSWER: fully
11. CFCs have the _____ ozone depletion potentials of any group of refrigerant.
ANSWER: highest
12. The most common HCFC refrigerant is ____.
ANSWER: R-22
13. All HCFC refrigerants are scheduled to be completely phased out in the U.S. on
January 1, ____.
ANSWER: 2030
14. HFC refrigerants are more _______ ________ than CFCs because they do not have
chlorine and therefore have no ozone depletion potential.
ANSWER: environmentally friendly
15. Blended refrigerants should be charged into a running system:
a. As a vapor into the high side.
b. As a liquid through a throttling valve into the low side.
c. As a liquid through a throttling valve into the high side.
d. As a vapor into the low side.
ANSWER: B (This ensures the blend composition does not change as it enters the
system)
16. High pressure refrigerants are used in the widest variety of applications and
have an evaporator saturation temperature between ____ and ____.
ANSWER: -20°F and 50°F
17. What are the two factors making up the safety classification for refrigerants?
a. Toxicity and time weighted average.
b. Flammability and toxicity.
c. Flammability and exposure levels.
d. ASHRAE standard 34 and 15.
ANSWER: B
18. The BTUs rejected at the condenser are always greater than the heat absorbed
in the evaporator because:
a. The condenser is mounted outside with restricted airflow.
NEWEST STUDY GUIDE||UPDATED
2026/2027 SYLLABUS EXAM
QUESTIONS AND CORRECT
SOLUTIONS||A+ GRADED
Unit Topic Focus Question Numbers
Unit
Refrigerants and System Fundamentals 1 - 18
1
Unit
Compressors and Oil Management 19 - 33
2
Unit
Condensers, Receivers, and Head Pressure Control 34 - 46
3
Unit
Metering Devices and Evaporators 47 - 68
4
Unit
System Accessories and Piping 69 - 82
5
Unit
Electrical Controls and Troubleshooting 83 - 107
6
Unit
System Applications and Special Topics 108 - 118
7
,Unit 1: Refrigerants and System Fundamentals
1. The ______ is the first component of a refrigeration system that must be
determined since its chemical and physical properties play a large role in selecting
the other components.
ANSWER: Refrigerant
2. Anything that can boil at a _____ temperature and condense at a _____
temperature can be used as a refrigerant.
ANSWER: boil at a high temperature; condense at a low temperature
3. Water could be used as a refrigerant if the pressure was adequately _____.
ANSWER: low (For example, it boils at 40°F if in a vacuum of 29.75 in Hg)
4. Refrigerants that utilize a change in latent heat are much more ______ than ones
that utilize a change in sensible heat.
ANSWER: efficient
5. The refrigerant's temperature is controlled by its _____.
ANSWER: pressure
6. PT charts are:
ANSWER: Pressure temperature charts. They correlate the saturation temperature and
pressure of commonly used refrigerants.
7. An indication of non-condensable gas in a refrigeration system is significantly:
a. Lower-than-normal suction pressures.
b. higher-than-normal suction pressures.
c. Lower-than-normal head pressures.
d. higher-than-normal head pressures.
ANSWER: D
8. What is the correct gauge pressure corresponding to an absolute pressure of
24.7 psia at sea level?
a. 10 psig.
b. 12.6 psig.
c. 39.4 psig.
d. 39.7 psig.
ANSWER: A
9. Refrigerants can be divided into five major chemical categories based on their
chemical composition. Name three of them.
, ANSWER: Hydrocarbons (HC), Chlorofluorocarbons (CFC), Hydrofluorocarbons (HFC),
Hydrochlorofluorocarbons (HCFC), Natural refrigerants (CO2, NH3).
10. CFCs (Chlorofluorocarbons) are ____ halogenated refrigerants.
ANSWER: fully
11. CFCs have the _____ ozone depletion potentials of any group of refrigerant.
ANSWER: highest
12. The most common HCFC refrigerant is ____.
ANSWER: R-22
13. All HCFC refrigerants are scheduled to be completely phased out in the U.S. on
January 1, ____.
ANSWER: 2030
14. HFC refrigerants are more _______ ________ than CFCs because they do not have
chlorine and therefore have no ozone depletion potential.
ANSWER: environmentally friendly
15. Blended refrigerants should be charged into a running system:
a. As a vapor into the high side.
b. As a liquid through a throttling valve into the low side.
c. As a liquid through a throttling valve into the high side.
d. As a vapor into the low side.
ANSWER: B (This ensures the blend composition does not change as it enters the
system)
16. High pressure refrigerants are used in the widest variety of applications and
have an evaporator saturation temperature between ____ and ____.
ANSWER: -20°F and 50°F
17. What are the two factors making up the safety classification for refrigerants?
a. Toxicity and time weighted average.
b. Flammability and toxicity.
c. Flammability and exposure levels.
d. ASHRAE standard 34 and 15.
ANSWER: B
18. The BTUs rejected at the condenser are always greater than the heat absorbed
in the evaporator because:
a. The condenser is mounted outside with restricted airflow.
