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HVAC Journeyman Exam Practice: Original Questions with Answers
Section 1: HVAC Theory & Fundamentals (Questions 1–15)
Q1. A technician measures the wet-bulb and dry-bulb temperatures of air entering an
evaporator coil. The purpose of determining these values is to calculate:
A. Refrigerant superheat only
B. Refrigerant subcooling only
C. Total heat content (enthalpy) of the air and system capacity
D. Compressor amp draw
Answer: C
Rationale: Wet-bulb and dry-bulb temperatures allow calculation of enthalpy (total heat
content) using the psychrometric chart. This determines system capacity (BTUH = CFM × 4.5
× Δh) and confirms proper dehumidification .
Q2. According to the Second Law of Thermodynamics, heat energy naturally flows:
A. From cold objects to hot objects with external work
B. From hot objects to cold objects without external work
C. Equally in both directions simultaneously
D. Only through radiation, not conduction or convection
Answer: B
Rationale: The Second Law states heat flows spontaneously from higher temperature to
lower temperature. External work (compressor) is required to move heat "uphill" (cold to
hot) in refrigeration cycles .
Q3. Sensible heat is defined as heat that:
A. Causes a change of state (latent heat)
B. Can be measured with a thermometer and causes temperature change
C. Is stored in refrigerant only
D. Cannot be calculated or measured
Answer: B
Rationale: Sensible heat causes temperature change measurable with a thermometer (Q = m
× c × ΔT). Latent heat causes phase change at constant temperature .
Q4. A system has 400 CFM per ton of cooling. If the system is 3 tons, what is the total
airflow?
A. 800 CFM
B. 1,200 CFM
C. 1,600 CFM
D. 2,400 CFM
, 2
Answer: B
Rationale: 3 tons × 400 CFM/ton = 1,200 CFM. Standard airflow for air conditioning is 350–
450 CFM per ton (typically 400) .
Q5. The boiling point of water at standard atmospheric pressure (14.7 psia) is 212°F. If
pressure is reduced to 10 psia, the boiling point will:
A. Increase to 240°F
B. Decrease to approximately 192°F
C. Remain at 212°F regardless of pressure
D. Increase to 250°F
Answer: B
Rationale: Boiling point varies with pressure—lower pressure = lower boiling point
(saturation temperature). At 10 psia, water boils at approximately 192°F .
Q6. What is the primary purpose of superheat measurement at the evaporator outlet?
A. To determine condenser subcooling levels
B. To verify complete evaporation of liquid refrigerant
C. To measure compressor discharge temperature
D. To calculate system electrical consumption
Answer: B
Rationale: Superheat ensures that all liquid refrigerant has vaporized before entering the
compressor, protecting it from liquid slugging damage .
Q7. A refrigeration technician is troubleshooting a system that exhibits low suction pressure,
high superheat, and reduced cooling capacity. Which condition is most likely causing this
symptom set?
A. Overcharged system with liquid floodback
B. Restricted refrigerant flow due to a partially blocked metering device
C. Excessively high evaporator load
D. Oversized condenser fan motor operation
Answer: B
Rationale: A restriction at the metering device reduces refrigerant flow into the evaporator,
causing starvation, elevated superheat, and low suction pressure while reducing overall
system capacity .
Q8. What is the effect of low refrigerant charge in a system?
A. High head pressure and low superheat
B. Low suction pressure and high superheat
C. High suction pressure and low compressor amperage
D. Normal pressures with increased cooling capacity
, 3
Answer: B
Rationale: Low refrigerant charge leads to insufficient evaporator feed, causing low suction
pressure and increased superheat due to evaporator starvation .
Q9. A system shows high head pressure during normal ambient conditions. Which issue is
most likely?
A. Undercharged refrigerant system
B. Dirty or blocked condenser coil
C. Excessively large evaporator coil
D. Low indoor heat load
Answer: B
Rationale: A dirty condenser restricts heat rejection, causing increased condensing pressure
and elevated head pressure .
Q10. Which of the following is the primary function of a condenser in a vapor-compression
refrigeration cycle?
A. To increase refrigerant pressure by mechanical compression
B. To absorb heat from the conditioned space
C. To reject heat from the refrigerant to a cooler medium
D. To meter refrigerant into the evaporator coil
Answer: C
Rationale: The condenser removes heat absorbed in the evaporator and heat of
compression, allowing the refrigerant to condense from a high-pressure vapor into a high-
pressure liquid .
Q11. What is a ton of refrigeration equal to in BTUs?
A. 1,200 BTUs
B. 12,000 BTUs
C. 120,000 BTUs
D. 1,200,000 BTUs
Answer: B
Rationale: One ton of refrigeration is equal to 12,000 BTUs per hour .
Q12. The difference between the boiling refrigerant temperature in the evaporator and the
outlet temperature is known as:
A. Subcooling
B. Superheat
C. Enthalpy
D. Sensible heat
HVAC Journeyman Exam Practice: Original Questions with Answers
Section 1: HVAC Theory & Fundamentals (Questions 1–15)
Q1. A technician measures the wet-bulb and dry-bulb temperatures of air entering an
evaporator coil. The purpose of determining these values is to calculate:
A. Refrigerant superheat only
B. Refrigerant subcooling only
C. Total heat content (enthalpy) of the air and system capacity
D. Compressor amp draw
Answer: C
Rationale: Wet-bulb and dry-bulb temperatures allow calculation of enthalpy (total heat
content) using the psychrometric chart. This determines system capacity (BTUH = CFM × 4.5
× Δh) and confirms proper dehumidification .
Q2. According to the Second Law of Thermodynamics, heat energy naturally flows:
A. From cold objects to hot objects with external work
B. From hot objects to cold objects without external work
C. Equally in both directions simultaneously
D. Only through radiation, not conduction or convection
Answer: B
Rationale: The Second Law states heat flows spontaneously from higher temperature to
lower temperature. External work (compressor) is required to move heat "uphill" (cold to
hot) in refrigeration cycles .
Q3. Sensible heat is defined as heat that:
A. Causes a change of state (latent heat)
B. Can be measured with a thermometer and causes temperature change
C. Is stored in refrigerant only
D. Cannot be calculated or measured
Answer: B
Rationale: Sensible heat causes temperature change measurable with a thermometer (Q = m
× c × ΔT). Latent heat causes phase change at constant temperature .
Q4. A system has 400 CFM per ton of cooling. If the system is 3 tons, what is the total
airflow?
A. 800 CFM
B. 1,200 CFM
C. 1,600 CFM
D. 2,400 CFM
, 2
Answer: B
Rationale: 3 tons × 400 CFM/ton = 1,200 CFM. Standard airflow for air conditioning is 350–
450 CFM per ton (typically 400) .
Q5. The boiling point of water at standard atmospheric pressure (14.7 psia) is 212°F. If
pressure is reduced to 10 psia, the boiling point will:
A. Increase to 240°F
B. Decrease to approximately 192°F
C. Remain at 212°F regardless of pressure
D. Increase to 250°F
Answer: B
Rationale: Boiling point varies with pressure—lower pressure = lower boiling point
(saturation temperature). At 10 psia, water boils at approximately 192°F .
Q6. What is the primary purpose of superheat measurement at the evaporator outlet?
A. To determine condenser subcooling levels
B. To verify complete evaporation of liquid refrigerant
C. To measure compressor discharge temperature
D. To calculate system electrical consumption
Answer: B
Rationale: Superheat ensures that all liquid refrigerant has vaporized before entering the
compressor, protecting it from liquid slugging damage .
Q7. A refrigeration technician is troubleshooting a system that exhibits low suction pressure,
high superheat, and reduced cooling capacity. Which condition is most likely causing this
symptom set?
A. Overcharged system with liquid floodback
B. Restricted refrigerant flow due to a partially blocked metering device
C. Excessively high evaporator load
D. Oversized condenser fan motor operation
Answer: B
Rationale: A restriction at the metering device reduces refrigerant flow into the evaporator,
causing starvation, elevated superheat, and low suction pressure while reducing overall
system capacity .
Q8. What is the effect of low refrigerant charge in a system?
A. High head pressure and low superheat
B. Low suction pressure and high superheat
C. High suction pressure and low compressor amperage
D. Normal pressures with increased cooling capacity
, 3
Answer: B
Rationale: Low refrigerant charge leads to insufficient evaporator feed, causing low suction
pressure and increased superheat due to evaporator starvation .
Q9. A system shows high head pressure during normal ambient conditions. Which issue is
most likely?
A. Undercharged refrigerant system
B. Dirty or blocked condenser coil
C. Excessively large evaporator coil
D. Low indoor heat load
Answer: B
Rationale: A dirty condenser restricts heat rejection, causing increased condensing pressure
and elevated head pressure .
Q10. Which of the following is the primary function of a condenser in a vapor-compression
refrigeration cycle?
A. To increase refrigerant pressure by mechanical compression
B. To absorb heat from the conditioned space
C. To reject heat from the refrigerant to a cooler medium
D. To meter refrigerant into the evaporator coil
Answer: C
Rationale: The condenser removes heat absorbed in the evaporator and heat of
compression, allowing the refrigerant to condense from a high-pressure vapor into a high-
pressure liquid .
Q11. What is a ton of refrigeration equal to in BTUs?
A. 1,200 BTUs
B. 12,000 BTUs
C. 120,000 BTUs
D. 1,200,000 BTUs
Answer: B
Rationale: One ton of refrigeration is equal to 12,000 BTUs per hour .
Q12. The difference between the boiling refrigerant temperature in the evaporator and the
outlet temperature is known as:
A. Subcooling
B. Superheat
C. Enthalpy
D. Sensible heat
