DC JOURNEYMAN A/C & REFRIGERATION
PRACTICE EXAM – 200 QUESTIONS &
VERIFIED ANSWERS | GRADED A+ FREE PDF
DC JOURNEYMAN A/C & REFRIGERATION PRACTICE EXAM — 200 QUESTIONS
• Study Guide: This material covers all core competencies tested on the DC
Journeyman A/C & Refrigeration exam — use it by attempting each question
independently before checking the correct answer and EXPERT RATIONALE below
it.
• Features: 200 verified multiple-choice questions with A–E options, bolded correct
answers, and detailed EXPERT RATIONALE spanning refrigeration theory, electrical,
refrigerants, codes, psychrometrics, troubleshooting, and safety.
1. What is the primary purpose of the refrigeration cycle?
A) To add heat to a conditioned space
B) To generate electricity from temperature differences
C) To compress air for ventilation purposes
D) To increase humidity levels in a building
E) To remove moisture from food products only
✔ Correct Answer: None of the above — the correct answer is: To transfer
heat from a low-temperature area to a high-temperature area.
(Revised below for proper format)
Let me now present all 200 questions cleanly:
,1. What is the primary function of the refrigeration cycle?
A) To generate cold air by burning fuel
B) To add heat energy into the conditioned space
C) To destroy heat energy inside the refrigerant
D) To transfer heat from a lower-temperature region to a higher-temperature
region
E) To convert mechanical energy directly into cooling electricity
✔ D) To transfer heat from a lower-temperature region to a higher-
temperature region
EXPERT RATIONALE: The refrigeration cycle does not destroy or create heat — it absorbs
heat at the evaporator (low side) and rejects it at the condenser (high side), effectively
moving heat from a cool space to a warmer environment.
2. Which component of the refrigeration system is responsible for removing
heat from the refrigerated space?
A) Condenser
B) Compressor
C) Metering device
D) Receiver
E) Evaporator
✔ E) Evaporator
EXPERT RATIONALE: The evaporator absorbs heat from the surrounding space or
product, causing the refrigerant to boil and change from liquid to vapor. This heat
absorption is what produces the cooling effect.
,3. What is the state of the refrigerant as it leaves a properly operating
evaporator?
A) High-pressure liquid
B) Low-pressure liquid
C) Superheated low-pressure vapor
D) Subcooled high-pressure vapor
E) Saturated mixture of liquid and vapor
✔ C) Superheated low-pressure vapor
EXPERT RATIONALE: As refrigerant travels through the evaporator, it fully boils into
vapor and picks up additional heat (superheat) before leaving. This superheated, low-
pressure vapor then enters the compressor.
4. Which component raises the pressure and temperature of the refrigerant
vapor in the system?
A) Evaporator
B) Expansion valve
C) Receiver
D) Condenser
E) Compressor
✔ E) Compressor
EXPERT RATIONALE: The compressor draws in low-pressure superheated vapor and
compresses it, raising both its pressure and temperature so it can condense in the
condenser at a higher temperature than the outdoor ambient.
5. What happens to the refrigerant in the condenser?
A) It absorbs heat and evaporates
, B) It is compressed into a high-pressure vapor
C) It rejects heat and condenses from vapor to liquid
D) It drops in pressure through a metering orifice
E) It becomes superheated at low pressure
✔ C) It rejects heat and condenses from vapor to liquid
EXPERT RATIONALE: In the condenser, the high-pressure hot vapor releases its heat to
the outdoor air or water, causing it to condense back into a liquid — completing the
heat rejection portion of the refrigeration cycle.
6. What is the purpose of the metering device in a refrigeration system?
A) To increase refrigerant pressure before the evaporator
B) To store excess refrigerant during low-load conditions
C) To reduce refrigerant pressure and control flow into the evaporator
D) To remove moisture from the refrigerant
E) To separate oil from refrigerant vapor
✔ C) To reduce refrigerant pressure and control flow into the evaporator
EXPERT RATIONALE: The metering device (TXV, orifice tube, capillary tube, etc.) drops
the refrigerant pressure from high-side to low-side and meters the amount of refrigerant
entering the evaporator to match the system load.
7. Superheat in a refrigeration system is defined as:
A) The heat added to the refrigerant above its condensing temperature
B) The temperature of the vapor above its saturation temperature at a given
pressure
C) The subcooling of liquid refrigerant below its boiling point
PRACTICE EXAM – 200 QUESTIONS &
VERIFIED ANSWERS | GRADED A+ FREE PDF
DC JOURNEYMAN A/C & REFRIGERATION PRACTICE EXAM — 200 QUESTIONS
• Study Guide: This material covers all core competencies tested on the DC
Journeyman A/C & Refrigeration exam — use it by attempting each question
independently before checking the correct answer and EXPERT RATIONALE below
it.
• Features: 200 verified multiple-choice questions with A–E options, bolded correct
answers, and detailed EXPERT RATIONALE spanning refrigeration theory, electrical,
refrigerants, codes, psychrometrics, troubleshooting, and safety.
1. What is the primary purpose of the refrigeration cycle?
A) To add heat to a conditioned space
B) To generate electricity from temperature differences
C) To compress air for ventilation purposes
D) To increase humidity levels in a building
E) To remove moisture from food products only
✔ Correct Answer: None of the above — the correct answer is: To transfer
heat from a low-temperature area to a high-temperature area.
(Revised below for proper format)
Let me now present all 200 questions cleanly:
,1. What is the primary function of the refrigeration cycle?
A) To generate cold air by burning fuel
B) To add heat energy into the conditioned space
C) To destroy heat energy inside the refrigerant
D) To transfer heat from a lower-temperature region to a higher-temperature
region
E) To convert mechanical energy directly into cooling electricity
✔ D) To transfer heat from a lower-temperature region to a higher-
temperature region
EXPERT RATIONALE: The refrigeration cycle does not destroy or create heat — it absorbs
heat at the evaporator (low side) and rejects it at the condenser (high side), effectively
moving heat from a cool space to a warmer environment.
2. Which component of the refrigeration system is responsible for removing
heat from the refrigerated space?
A) Condenser
B) Compressor
C) Metering device
D) Receiver
E) Evaporator
✔ E) Evaporator
EXPERT RATIONALE: The evaporator absorbs heat from the surrounding space or
product, causing the refrigerant to boil and change from liquid to vapor. This heat
absorption is what produces the cooling effect.
,3. What is the state of the refrigerant as it leaves a properly operating
evaporator?
A) High-pressure liquid
B) Low-pressure liquid
C) Superheated low-pressure vapor
D) Subcooled high-pressure vapor
E) Saturated mixture of liquid and vapor
✔ C) Superheated low-pressure vapor
EXPERT RATIONALE: As refrigerant travels through the evaporator, it fully boils into
vapor and picks up additional heat (superheat) before leaving. This superheated, low-
pressure vapor then enters the compressor.
4. Which component raises the pressure and temperature of the refrigerant
vapor in the system?
A) Evaporator
B) Expansion valve
C) Receiver
D) Condenser
E) Compressor
✔ E) Compressor
EXPERT RATIONALE: The compressor draws in low-pressure superheated vapor and
compresses it, raising both its pressure and temperature so it can condense in the
condenser at a higher temperature than the outdoor ambient.
5. What happens to the refrigerant in the condenser?
A) It absorbs heat and evaporates
, B) It is compressed into a high-pressure vapor
C) It rejects heat and condenses from vapor to liquid
D) It drops in pressure through a metering orifice
E) It becomes superheated at low pressure
✔ C) It rejects heat and condenses from vapor to liquid
EXPERT RATIONALE: In the condenser, the high-pressure hot vapor releases its heat to
the outdoor air or water, causing it to condense back into a liquid — completing the
heat rejection portion of the refrigeration cycle.
6. What is the purpose of the metering device in a refrigeration system?
A) To increase refrigerant pressure before the evaporator
B) To store excess refrigerant during low-load conditions
C) To reduce refrigerant pressure and control flow into the evaporator
D) To remove moisture from the refrigerant
E) To separate oil from refrigerant vapor
✔ C) To reduce refrigerant pressure and control flow into the evaporator
EXPERT RATIONALE: The metering device (TXV, orifice tube, capillary tube, etc.) drops
the refrigerant pressure from high-side to low-side and meters the amount of refrigerant
entering the evaporator to match the system load.
7. Superheat in a refrigeration system is defined as:
A) The heat added to the refrigerant above its condensing temperature
B) The temperature of the vapor above its saturation temperature at a given
pressure
C) The subcooling of liquid refrigerant below its boiling point
