Colorado HVAC Contractor Licensing
Exam Practice Questions With Correct
Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant
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1. What is the primary purpose of a Manual J load calculation?
A. To determine refrigerant charge
B. To calculate heating and cooling loads for a building
C. To size duct insulation
D. To measure airflow velocity
Answer: B. To calculate heating and cooling loads for a building
Rationale: Manual J calculations are used to determine the heating and
cooling requirements of a structure. Accurate load calculations ensure
HVAC systems are properly sized for efficiency, comfort, and code
compliance.
2. Which refrigerant has the highest ozone depletion potential?
A. R-410A
B. R-134a
C. R-22
D. R-32
Answer: C. R-22
,Rationale: R-22 is an HCFC refrigerant with ozone depletion potential. It
has been phased out due to environmental regulations under the Clean
Air Act.
3. What component in an air conditioning system removes moisture
from the air?
A. Compressor
B. Evaporator coil
C. Expansion valve
D. Condenser fan
Answer: B. Evaporator coil
Rationale: As warm indoor air passes over the cold evaporator coil,
moisture condenses and is removed from the air, lowering indoor
humidity levels.
4. Which instrument measures electrical resistance?
A. Ammeter
B. Voltmeter
C. Ohmmeter
D. Manometer
Answer: C. Ohmmeter
Rationale: An ohmmeter measures resistance in electrical circuits and
components. It is commonly used to test motors, capacitors, and wiring
continuity.
, 5. What is the minimum required clearance around most gas
furnaces for service access according to manufacturer
specifications?
A. 1 inch
B. 3 inches
C. Varies by manufacturer
D. 24 inches exactly
Answer: C. Varies by manufacturer
Rationale: Manufacturers specify required service clearances for
equipment. Technicians must follow installation instructions and
applicable mechanical codes.
6. Which type of motor is commonly used in residential furnace
blowers?
A. Stepper motor
B. ECM motor
C. Servo motor
D. Hydraulic motor
Answer: B. ECM motor
Rationale: Electronically Commutated Motors (ECMs) are energy-
efficient variable-speed motors widely used in modern HVAC systems.
7. Superheat is measured at which location?
, A. Compressor discharge
B. Condenser outlet
C. Evaporator outlet
D. Expansion valve inlet
Answer: C. Evaporator outlet
Rationale: Superheat is the temperature of refrigerant vapor above its
saturation point and is measured at the evaporator outlet.
8. What is the purpose of a TXV in a refrigeration system?
A. Increase compressor speed
B. Control refrigerant flow into the evaporator
C. Raise condensing pressure
D. Eliminate moisture from refrigerant
Answer: B. Control refrigerant flow into the evaporator
Rationale: A thermostatic expansion valve regulates refrigerant flow
based on evaporator load conditions, improving efficiency and
preventing floodback.
9. Which gas is commonly used for pressure testing refrigerant lines?
A. Oxygen
B. Acetylene
C. Nitrogen
D. Propane
Answer: C. Nitrogen
Exam Practice Questions With Correct
Answers (Verified Answers) Plus
Rationales 2026 Q&A | Instant
Download Pdf
1. What is the primary purpose of a Manual J load calculation?
A. To determine refrigerant charge
B. To calculate heating and cooling loads for a building
C. To size duct insulation
D. To measure airflow velocity
Answer: B. To calculate heating and cooling loads for a building
Rationale: Manual J calculations are used to determine the heating and
cooling requirements of a structure. Accurate load calculations ensure
HVAC systems are properly sized for efficiency, comfort, and code
compliance.
2. Which refrigerant has the highest ozone depletion potential?
A. R-410A
B. R-134a
C. R-22
D. R-32
Answer: C. R-22
,Rationale: R-22 is an HCFC refrigerant with ozone depletion potential. It
has been phased out due to environmental regulations under the Clean
Air Act.
3. What component in an air conditioning system removes moisture
from the air?
A. Compressor
B. Evaporator coil
C. Expansion valve
D. Condenser fan
Answer: B. Evaporator coil
Rationale: As warm indoor air passes over the cold evaporator coil,
moisture condenses and is removed from the air, lowering indoor
humidity levels.
4. Which instrument measures electrical resistance?
A. Ammeter
B. Voltmeter
C. Ohmmeter
D. Manometer
Answer: C. Ohmmeter
Rationale: An ohmmeter measures resistance in electrical circuits and
components. It is commonly used to test motors, capacitors, and wiring
continuity.
, 5. What is the minimum required clearance around most gas
furnaces for service access according to manufacturer
specifications?
A. 1 inch
B. 3 inches
C. Varies by manufacturer
D. 24 inches exactly
Answer: C. Varies by manufacturer
Rationale: Manufacturers specify required service clearances for
equipment. Technicians must follow installation instructions and
applicable mechanical codes.
6. Which type of motor is commonly used in residential furnace
blowers?
A. Stepper motor
B. ECM motor
C. Servo motor
D. Hydraulic motor
Answer: B. ECM motor
Rationale: Electronically Commutated Motors (ECMs) are energy-
efficient variable-speed motors widely used in modern HVAC systems.
7. Superheat is measured at which location?
, A. Compressor discharge
B. Condenser outlet
C. Evaporator outlet
D. Expansion valve inlet
Answer: C. Evaporator outlet
Rationale: Superheat is the temperature of refrigerant vapor above its
saturation point and is measured at the evaporator outlet.
8. What is the purpose of a TXV in a refrigeration system?
A. Increase compressor speed
B. Control refrigerant flow into the evaporator
C. Raise condensing pressure
D. Eliminate moisture from refrigerant
Answer: B. Control refrigerant flow into the evaporator
Rationale: A thermostatic expansion valve regulates refrigerant flow
based on evaporator load conditions, improving efficiency and
preventing floodback.
9. Which gas is commonly used for pressure testing refrigerant lines?
A. Oxygen
B. Acetylene
C. Nitrogen
D. Propane
Answer: C. Nitrogen
