Georgia Conditioned Air Contractor
Class Ii Professional Examination
Questions And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
Question 1
What is the primary purpose of a thermostat in an HVAC system?
A. To regulate refrigerant flow
B. To control indoor humidity
C. To maintain set temperature by cycling equipment
D. To increase airflow velocity
Answer: A
Rationale: A thermostat’s primary function is to sense indoor temperature and
regulate system operation accordingly. It controls the on/off cycling of heating
and cooling equipment to maintain the setpoint, ensuring comfort and energy
efficiency. While it indirectly affects humidity and airflow by system operation,
its core role is temperature control.
Question 2
Which refrigerant pressure side is associated with the compressor discharge?
A. Low-pressure side
B. Intermediate-pressure side
C. Vacuum side
D. High-pressure side
,Answer: B
Rationale: The compressor discharge is typically associated with the high-
pressure side of the refrigeration system. After compression, refrigerant leaves
the compressor as a high-pressure, high-temperature vapor. This is fundamental
to vapor compression cycle operation.
Question 3
What is the standard voltage for residential HVAC control circuits?
A. 120V
B. 24V
C. 240V
D. 480V
Answer: C
Rationale: HVAC control circuits in residential systems commonly operate at 24
volts AC. This low voltage ensures safety while allowing reliable switching of
relays, contactors, and control components within the system.
Question 4
Which component removes moisture from air in an air conditioning system?
A. Compressor
B. Evaporator coil
C. Condenser coil
D. Expansion valve
Answer: D
Rationale: The expansion valve controls refrigerant flow into the evaporator coil,
where cooling occurs and moisture condenses from the air. However, the
evaporator coil itself is the primary location where dehumidification occurs as
air passes over the cold surface.
,Question 5
What refrigerant property determines its ability to absorb heat?
A. Density
B. Latent heat of vaporization
C. Specific gravity
D. Viscosity
Answer: A
Rationale: Refrigerant effectiveness is largely based on latent heat of
vaporization, which is the amount of heat absorbed during phase change from
liquid to vapor. This property enables efficient heat transfer in HVAC systems.
Question 6
What is the function of a condenser in an HVAC system?
A. Absorb indoor heat
B. Release heat to the outdoor environment
C. Control refrigerant flow
D. Measure system pressure
Answer: B
Rationale: The condenser rejects heat absorbed from indoors to the outdoor
environment by condensing high-pressure refrigerant vapor into liquid. This heat
rejection is essential for the refrigeration cycle.
Question 7
Which tool is used to measure electrical current in HVAC diagnostics?
A. Thermometer
B. Manifold gauge
C. Clamp ammeter
D. Psychrometer
, Answer: C
Rationale: A clamp ammeter measures electrical current without breaking the
circuit. It is essential for diagnosing motors, compressors, and other electrical
HVAC components.
Question 8
What does SEER rating measure?
A. Sound efficiency
B. Seasonal energy efficiency ratio
C. Static efficiency energy rating
D. System electrical emission rate
Answer: D
Rationale: SEER (Seasonal Energy Efficiency Ratio) measures cooling output over
a typical cooling season divided by energy consumed. It is a key efficiency metric
for air conditioning systems.
Question 9
What is the purpose of refrigerant subcooling?
A. Increase compressor speed
B. Ensure liquid refrigerant at expansion device
C. Reduce airflow resistance
D. Increase suction pressure
Answer: A
Rationale: Subcooling ensures refrigerant remains in liquid form before entering
the expansion device, preventing flash gas formation and improving system
efficiency and reliability.
Class Ii Professional Examination
Questions And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
Question 1
What is the primary purpose of a thermostat in an HVAC system?
A. To regulate refrigerant flow
B. To control indoor humidity
C. To maintain set temperature by cycling equipment
D. To increase airflow velocity
Answer: A
Rationale: A thermostat’s primary function is to sense indoor temperature and
regulate system operation accordingly. It controls the on/off cycling of heating
and cooling equipment to maintain the setpoint, ensuring comfort and energy
efficiency. While it indirectly affects humidity and airflow by system operation,
its core role is temperature control.
Question 2
Which refrigerant pressure side is associated with the compressor discharge?
A. Low-pressure side
B. Intermediate-pressure side
C. Vacuum side
D. High-pressure side
,Answer: B
Rationale: The compressor discharge is typically associated with the high-
pressure side of the refrigeration system. After compression, refrigerant leaves
the compressor as a high-pressure, high-temperature vapor. This is fundamental
to vapor compression cycle operation.
Question 3
What is the standard voltage for residential HVAC control circuits?
A. 120V
B. 24V
C. 240V
D. 480V
Answer: C
Rationale: HVAC control circuits in residential systems commonly operate at 24
volts AC. This low voltage ensures safety while allowing reliable switching of
relays, contactors, and control components within the system.
Question 4
Which component removes moisture from air in an air conditioning system?
A. Compressor
B. Evaporator coil
C. Condenser coil
D. Expansion valve
Answer: D
Rationale: The expansion valve controls refrigerant flow into the evaporator coil,
where cooling occurs and moisture condenses from the air. However, the
evaporator coil itself is the primary location where dehumidification occurs as
air passes over the cold surface.
,Question 5
What refrigerant property determines its ability to absorb heat?
A. Density
B. Latent heat of vaporization
C. Specific gravity
D. Viscosity
Answer: A
Rationale: Refrigerant effectiveness is largely based on latent heat of
vaporization, which is the amount of heat absorbed during phase change from
liquid to vapor. This property enables efficient heat transfer in HVAC systems.
Question 6
What is the function of a condenser in an HVAC system?
A. Absorb indoor heat
B. Release heat to the outdoor environment
C. Control refrigerant flow
D. Measure system pressure
Answer: B
Rationale: The condenser rejects heat absorbed from indoors to the outdoor
environment by condensing high-pressure refrigerant vapor into liquid. This heat
rejection is essential for the refrigeration cycle.
Question 7
Which tool is used to measure electrical current in HVAC diagnostics?
A. Thermometer
B. Manifold gauge
C. Clamp ammeter
D. Psychrometer
, Answer: C
Rationale: A clamp ammeter measures electrical current without breaking the
circuit. It is essential for diagnosing motors, compressors, and other electrical
HVAC components.
Question 8
What does SEER rating measure?
A. Sound efficiency
B. Seasonal energy efficiency ratio
C. Static efficiency energy rating
D. System electrical emission rate
Answer: D
Rationale: SEER (Seasonal Energy Efficiency Ratio) measures cooling output over
a typical cooling season divided by energy consumed. It is a key efficiency metric
for air conditioning systems.
Question 9
What is the purpose of refrigerant subcooling?
A. Increase compressor speed
B. Ensure liquid refrigerant at expansion device
C. Reduce airflow resistance
D. Increase suction pressure
Answer: A
Rationale: Subcooling ensures refrigerant remains in liquid form before entering
the expansion device, preventing flash gas formation and improving system
efficiency and reliability.
