ASE T7 HVAC Practice Exam Questions

ASE T7 HVAC Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• What is the primary function of a compressor in an HVAC system?
• Expand refrigerant
• Increase refrigerant pressure and temperature
• Remove humidity from the air
• Filter contaminants from the refrigerant

Rationale: The compressor raises the pressure and temperature of the

refrigerant, enabling it to release heat in the condenser.

• Which type of refrigerant is most commonly used in modern

residential HVAC systems?

A. R-12

B. R-410A 1 / 4

C. R-22

D. R-134

Rationale: R-410A has replaced R-22 due to environmental regulations,

particularly regarding ozone depletion.

• What is the purpose of the expansion device in a cooling system?
• Heat the refrigerant
• Reduce refrigerant pressure and temperature
• Compress refrigerant
• Remove air from the system

Rationale: The expansion device lowers the pressure of the refrigerant,

allowing it to absorb heat in the evaporator.

• Which instrument is used to measure superheat in an air conditioning

system?

• Thermometer
• Manifold gauge set and temperature probe
• Vacuum gauge
• Amp meter

Rationale: Superheat is measured by comparing the refrigerant vapor

temperature at the evaporator outlet to the saturation temperature at the corresponding pressure.

• What is the primary purpose of an air filter in an HVAC system?
• Cool the air 2 / 4

• Remove dust and particles from the air
• Heat the air
• Regulate refrigerant flow

Rationale: Air filters prevent dust, dirt, and debris from entering the system

and damaging components.

• Which component removes heat from the refrigerant in a cooling

system?

• Evaporator
• Expansion valve
• Condenser
• Compressor

Rationale: The condenser transfers heat from the high-pressure refrigerant

to the surrounding air or water.

• What is the ideal superheat reading at the evaporator outlet for

proper system performance?

A. 0–2°F

B. 3–5°F

C. 8–12°F

D. 15–20°F

Rationale: 8–12°F of superheat ensures the evaporator is fully vaporized,

preventing liquid refrigerant from reaching the compressor. 3 / 4

• What is the primary function of a thermostat in an HVAC system?
• Increase airflow
• Control system operation based on temperature
• Filter the air
• Dehumidify the air

Rationale: Thermostats sense temperature and signal the system to turn on

or off to maintain comfort levels.

• Which of the following indicates a refrigerant leak?
• High amperage draw
• Frost on the evaporator coil
• Low airflow
• Compressor noise

Rationale: Frost can form on the evaporator coil if refrigerant levels are low

due to a leak.

• What type of expansion device uses a sensing bulb to control

refrigerant flow?

• Fixed orifice
• Thermostatic expansion valve (TXV)
• Capillary tube
• Solenoid valve

Rationale: TXVs use a sensing bulb to adjust refrigerant flow based on

evaporator temperature.

• / 4