,PE HVAC & Refrigeration Systems Practice Exam Questions, Correct
Answers, and Detailed Explanations for Students||Already Graded A+
Question 1
A comfort cooling system is designed to maintain an indoor dry-bulb
temperature of 75°F and a relative humidity of 50%. Which HVAC
component is primarily responsible for removing latent heat from the
air?
A. Condenser coil
B. Evaporator coil
C. Expansion valve
D. Compressor
Correct Answer: B. Evaporator coil
Explanation:
The evaporator coil removes both sensible and latent heat. As warm,
humid air passes over the cold coil, moisture condenses on the coil
surface, reducing indoor humidity while cooling the air.
Question 2
Which refrigeration cycle component increases the pressure and
temperature of the refrigerant vapor?
A. Expansion valve
B. Condenser
C. Compressor
D. Evaporator
Correct Answer: C. Compressor
,Explanation:
The compressor draws low-pressure refrigerant vapor from the
evaporator and compresses it into a high-pressure, high-temperature
vapor before sending it to the condenser.
Question 3
The primary purpose of the condenser in a vapor-compression
refrigeration system is to:
A. Evaporate refrigerant
B. Compress refrigerant vapor
C. Reject heat to the surroundings
D. Meter refrigerant flow
Correct Answer: C. Reject heat to the surroundings
Explanation:
The condenser transfers heat absorbed in the evaporator plus the
compressor work to the outdoor air or cooling water, causing the
refrigerant to condense into a liquid.
Question 4
Which psychrometric process occurs when moisture is removed from
air while lowering its temperature?
A. Sensible heating
B. Sensible cooling
C. Cooling and dehumidification
D. Heating and humidification
, Correct Answer: C. Cooling and dehumidification
Explanation:
When air is cooled below its dew point, water vapor condenses out,
reducing both temperature and humidity.
Question 5
In an air-handling unit (AHU), the purpose of the air filter is to:
A. Increase airflow velocity
B. Remove contaminants from the air
C. Increase refrigerant pressure
D. Reduce compressor power
Correct Answer: B. Remove contaminants from the air
Explanation:
Air filters remove dust, pollen, and other airborne particles, improving
indoor air quality and protecting HVAC equipment.
Question 6
Which refrigerant property makes it particularly effective for heat
transfer?
A. High molecular weight
B. Low latent heat
C. High latent heat of vaporization
D. High viscosity
Correct Answer: C. High latent heat of vaporization
Answers, and Detailed Explanations for Students||Already Graded A+
Question 1
A comfort cooling system is designed to maintain an indoor dry-bulb
temperature of 75°F and a relative humidity of 50%. Which HVAC
component is primarily responsible for removing latent heat from the
air?
A. Condenser coil
B. Evaporator coil
C. Expansion valve
D. Compressor
Correct Answer: B. Evaporator coil
Explanation:
The evaporator coil removes both sensible and latent heat. As warm,
humid air passes over the cold coil, moisture condenses on the coil
surface, reducing indoor humidity while cooling the air.
Question 2
Which refrigeration cycle component increases the pressure and
temperature of the refrigerant vapor?
A. Expansion valve
B. Condenser
C. Compressor
D. Evaporator
Correct Answer: C. Compressor
,Explanation:
The compressor draws low-pressure refrigerant vapor from the
evaporator and compresses it into a high-pressure, high-temperature
vapor before sending it to the condenser.
Question 3
The primary purpose of the condenser in a vapor-compression
refrigeration system is to:
A. Evaporate refrigerant
B. Compress refrigerant vapor
C. Reject heat to the surroundings
D. Meter refrigerant flow
Correct Answer: C. Reject heat to the surroundings
Explanation:
The condenser transfers heat absorbed in the evaporator plus the
compressor work to the outdoor air or cooling water, causing the
refrigerant to condense into a liquid.
Question 4
Which psychrometric process occurs when moisture is removed from
air while lowering its temperature?
A. Sensible heating
B. Sensible cooling
C. Cooling and dehumidification
D. Heating and humidification
, Correct Answer: C. Cooling and dehumidification
Explanation:
When air is cooled below its dew point, water vapor condenses out,
reducing both temperature and humidity.
Question 5
In an air-handling unit (AHU), the purpose of the air filter is to:
A. Increase airflow velocity
B. Remove contaminants from the air
C. Increase refrigerant pressure
D. Reduce compressor power
Correct Answer: B. Remove contaminants from the air
Explanation:
Air filters remove dust, pollen, and other airborne particles, improving
indoor air quality and protecting HVAC equipment.
Question 6
Which refrigerant property makes it particularly effective for heat
transfer?
A. High molecular weight
B. Low latent heat
C. High latent heat of vaporization
D. High viscosity
Correct Answer: C. High latent heat of vaporization
