HVAC Systems Installation –
Practice Exam (80+ Questions)
:Questions and answer with
rationals/graded A+Update/100%
correct
Section 1: Safety & Tool Identification (Questions 1–12)
1. What is the minimum required PPE when brazing refrigerant lines?
a) Safety glasses only
b) Leather gloves + shade 4 goggles
c) Torch-resistant gloves + shaded face shield + long sleeves
d) Disposable dust mask and earplugs
Rationale: Brazing produces intense UV light, sparks, and heat. Gloves and face
shield prevent burns; shade 4 or darker lens protects eyes from flash.
2. Which of the following is the correct procedure after a refrigerant release
alarm sounds in an occupied building?
a) Immediately enter to locate the leak
b) Evacuate, ventilate, and call emergency contact per SDS
c) Reset the alarm and continue work
d) Open all windows and use a fan
Rationale: New 2026 OSHA/EPA rules require immediate evacuation for refrigerant
leaks, especially A2L mildly flammable types. Ventilation comes after safe egress.
3. A combustion analyzer is used to check:
a) Refrigerant superheat
b) Flue gas O₂ and CO levels in gas furnaces
c) Blower motor amperage
d) Duct static pressure
, 4. The safe distance for storing an oxygen cylinder from an acetylene cylinder
is:
a) 5 feet
b) 20 feet (or 5 feet with non-combustible barrier at least 5 ft high with 30-min
fire rating)
c) 10 feet
d) 50 feet
5. R-454B (A2L) requires which special safety practice during installation?
a) Must use only copper-rated for R-410A pressures
b) Leak detection system required in occupied spaces
c) Cannot be used in variable refrigerant flow (VRF) systems
d) Must be charged as a liquid only
Rationale: A2L refrigerants are mildly flammable. 2024 IMC/IECC updates mandate
refrigerant detectors in mechanical rooms and occupied zones for systems exceeding
certain charge limits.
6. What type of ladder is required to access a roof hatch with a 6 ft parapet?
a) Step ladder
b) Extension ladder extending at least 3 ft above landing
c) Extension ladder extending at least 42 inches (3 ft 6 in) above hatch
d) Platform ladder
7. A torque wrench is necessary when:
a) Cutting ductwork
b) Installing ductless mini-split flare connections
c) Tightening flare nuts to manufacturer specification
d) Mounting thermostat wire
Rationale: Over-torquing splits flare nuts; under-torquing causes leaks. 2026 training
emphasizes digital torque wrenches for A2L systems.
8. Non-condensable gases in a refrigeration circuit cause:
a) Lower compression ratio
b) High head pressure and high discharge temperature
c) Low evaporator pressure
d) Oil foaming
9. Isolating a rooftop unit (RTU) for electrical service requires:
a) Turning thermostat to OFF
b) Lockout/tagout (LOTO) of disconnect within sight of the unit
c) Unplugging the transformer
d) Closing manual gas valve only
Practice Exam (80+ Questions)
:Questions and answer with
rationals/graded A+Update/100%
correct
Section 1: Safety & Tool Identification (Questions 1–12)
1. What is the minimum required PPE when brazing refrigerant lines?
a) Safety glasses only
b) Leather gloves + shade 4 goggles
c) Torch-resistant gloves + shaded face shield + long sleeves
d) Disposable dust mask and earplugs
Rationale: Brazing produces intense UV light, sparks, and heat. Gloves and face
shield prevent burns; shade 4 or darker lens protects eyes from flash.
2. Which of the following is the correct procedure after a refrigerant release
alarm sounds in an occupied building?
a) Immediately enter to locate the leak
b) Evacuate, ventilate, and call emergency contact per SDS
c) Reset the alarm and continue work
d) Open all windows and use a fan
Rationale: New 2026 OSHA/EPA rules require immediate evacuation for refrigerant
leaks, especially A2L mildly flammable types. Ventilation comes after safe egress.
3. A combustion analyzer is used to check:
a) Refrigerant superheat
b) Flue gas O₂ and CO levels in gas furnaces
c) Blower motor amperage
d) Duct static pressure
, 4. The safe distance for storing an oxygen cylinder from an acetylene cylinder
is:
a) 5 feet
b) 20 feet (or 5 feet with non-combustible barrier at least 5 ft high with 30-min
fire rating)
c) 10 feet
d) 50 feet
5. R-454B (A2L) requires which special safety practice during installation?
a) Must use only copper-rated for R-410A pressures
b) Leak detection system required in occupied spaces
c) Cannot be used in variable refrigerant flow (VRF) systems
d) Must be charged as a liquid only
Rationale: A2L refrigerants are mildly flammable. 2024 IMC/IECC updates mandate
refrigerant detectors in mechanical rooms and occupied zones for systems exceeding
certain charge limits.
6. What type of ladder is required to access a roof hatch with a 6 ft parapet?
a) Step ladder
b) Extension ladder extending at least 3 ft above landing
c) Extension ladder extending at least 42 inches (3 ft 6 in) above hatch
d) Platform ladder
7. A torque wrench is necessary when:
a) Cutting ductwork
b) Installing ductless mini-split flare connections
c) Tightening flare nuts to manufacturer specification
d) Mounting thermostat wire
Rationale: Over-torquing splits flare nuts; under-torquing causes leaks. 2026 training
emphasizes digital torque wrenches for A2L systems.
8. Non-condensable gases in a refrigeration circuit cause:
a) Lower compression ratio
b) High head pressure and high discharge temperature
c) Low evaporator pressure
d) Oil foaming
9. Isolating a rooftop unit (RTU) for electrical service requires:
a) Turning thermostat to OFF
b) Lockout/tagout (LOTO) of disconnect within sight of the unit
c) Unplugging the transformer
d) Closing manual gas valve only
