Nevada C 21B Air Conditioning Contractor
Mega Bundle Exam 2026/2027 Complete
Licensing Practice Questions and Verified
Answers Study Guide
NEVADA C 21B AIR CONDITIONING CONTRACTOR MEGA BUNDLE EXAM 2026-
2027 Complete Licensing Practice Questions and Verified Answers Study Guide
• This comprehensive study guide contains 200 verified practice questions covering
all Nevada C 21B Air Conditioning Contractor licensing exam domains, with detailed
EXPERT RATIONALE to reinforce learning and exam readiness.
• Study this material by working through all questions systematically, reviewing
EXPERT RATIONALE for both correct and missed answers, and focusing on weak
topic areas for mastery of HVAC systems, codes, safety, and contractor
responsibilities.
1. QUESTION: Which of the following is the primary responsibility of an air
conditioning contractor in Nevada?
A) To install only residential cooling systems regardless of local codes
B) To diagnose, repair, and install air conditioning systems in compliance with
Nevada state codes and local regulations
C) To perform electrical work without a licensed electrician on large commercial
projects
D) To charge arbitrary prices for service calls without providing written estimates
E) To operate unlicensed apprentices without supervision on job sites
CORRECT ANSWER: B) To diagnose, repair, and install air conditioning systems
in compliance with Nevada state codes and local regulations
EXPERT RATIONALE: Nevada regulations for C 21B contractors mandate that all
work must comply with state codes and local jurisdiction requirements. Contractors
are responsible for ensuring systems meet safety standards, proper installation
,codes, and environmental regulations. Options A, C, D, and E all violate Nevada
contractor regulations.
2. QUESTION: What is the minimum EPA certification level required for
technicians working with refrigerants in Nevada?
A) Level 1 only for small systems
B) EPA Section 608 Type II certification minimum
C) No certification required if supervised by a contractor
D) Basic training certificate from any HVAC school
E) State-issued permit instead of EPA certification
CORRECT ANSWER: B) EPA Section 608 Type II certification minimum
EXPERT RATIONALE: Federal and Nevada state law require technicians handling
refrigerants to maintain at least EPA Section 608 Type II certification (small
appliances and commercial equipment). Type I is for small appliances only, Type II
covers high-pressure appliances, and Type III covers low-pressure systems. Many
contractors require their technicians to hold universal Type III certification for
broader capability.
3. QUESTION: Which refrigerant is classified as a Class A1 non-toxic, non-
flammable substance?
A) R-410A
B) R-404A
C) R-22
D) R-290 (propane)
E) R-717 (ammonia)
CORRECT ANSWER: A) R-410A
,EXPERT RATIONALE: R-410A is classified as Class A1, indicating it is non-toxic and
non-flammable, making it safe for residential and commercial applications. R-22 is
an HCFC being phased out due to ozone depletion. R-290 and R-717 are flammable
and toxic respectively. R-404A is a safer alternative but not Class A1.
4. QUESTION: What is the maximum allowable pressure drop in a residential
air conditioning refrigerant line set?
A) 0.5 PSI per 100 feet
B) 2 PSI per 100 feet
C) 5 PSI per 100 feet
D) 10 PSI per 100 feet
E) 15 PSI per 100 feet
CORRECT ANSWER: B) 2 PSI per 100 feet
EXPERT RATIONALE: Industry standards and Nevada code requirements specify
that pressure drop in refrigerant lines should not exceed 2 PSI per 100 feet of line
length. Excessive pressure drop reduces system efficiency, increases compressor
load, and shortens system lifespan. Proper line sizing and installation prevent these
issues.
5. QUESTION: Which type of thermostat control is required for modern
energy-efficient commercial air conditioning systems in Nevada?
A) Mercury bulb thermostat only
B) Programmable or smart thermostat with setpoint control
C) Manual on-off switch
D) Mechanical expansion valve control
E) Pressure-actuated control valve
, CORRECT ANSWER: B) Programmable or smart thermostat with setpoint
control
EXPERT RATIONALE: Nevada building codes and energy efficiency standards now
require programmable thermostats that allow temperature setpoint control,
occupancy scheduling, and demand-controlled ventilation in commercial buildings.
This improves energy efficiency and meets state compliance requirements.
6. QUESTION: What is the proper procedure for evacuating an air conditioning
system before refrigerant recovery?
A) Quickly open all connections to release pressure
B) Use a vacuum pump to pull system pressure below 500 microns
C) Vent refrigerant to the atmosphere using a recovery line
D) Flush the system with nitrogen gas at high pressure
E) Disconnect hoses and allow system to naturally depressurize
CORRECT ANSWER: B) Use a vacuum pump to pull system pressure below 500
microns
EXPERT RATIONALE: Proper evacuation removes non-condensable gases and
moisture from the system, which is critical for system reliability and longevity. EPA
regulations prohibit venting refrigerants. A vacuum pump must reduce system
pressure to below 500 microns of mercury for adequate evacuation, ensuring
system integrity.
7. QUESTION: Which component is responsible for metering refrigerant flow
into the evaporator coil?
A) Accumulator
B) Condenser
C) Expansion device (TXV or capillary tube)
Mega Bundle Exam 2026/2027 Complete
Licensing Practice Questions and Verified
Answers Study Guide
NEVADA C 21B AIR CONDITIONING CONTRACTOR MEGA BUNDLE EXAM 2026-
2027 Complete Licensing Practice Questions and Verified Answers Study Guide
• This comprehensive study guide contains 200 verified practice questions covering
all Nevada C 21B Air Conditioning Contractor licensing exam domains, with detailed
EXPERT RATIONALE to reinforce learning and exam readiness.
• Study this material by working through all questions systematically, reviewing
EXPERT RATIONALE for both correct and missed answers, and focusing on weak
topic areas for mastery of HVAC systems, codes, safety, and contractor
responsibilities.
1. QUESTION: Which of the following is the primary responsibility of an air
conditioning contractor in Nevada?
A) To install only residential cooling systems regardless of local codes
B) To diagnose, repair, and install air conditioning systems in compliance with
Nevada state codes and local regulations
C) To perform electrical work without a licensed electrician on large commercial
projects
D) To charge arbitrary prices for service calls without providing written estimates
E) To operate unlicensed apprentices without supervision on job sites
CORRECT ANSWER: B) To diagnose, repair, and install air conditioning systems
in compliance with Nevada state codes and local regulations
EXPERT RATIONALE: Nevada regulations for C 21B contractors mandate that all
work must comply with state codes and local jurisdiction requirements. Contractors
are responsible for ensuring systems meet safety standards, proper installation
,codes, and environmental regulations. Options A, C, D, and E all violate Nevada
contractor regulations.
2. QUESTION: What is the minimum EPA certification level required for
technicians working with refrigerants in Nevada?
A) Level 1 only for small systems
B) EPA Section 608 Type II certification minimum
C) No certification required if supervised by a contractor
D) Basic training certificate from any HVAC school
E) State-issued permit instead of EPA certification
CORRECT ANSWER: B) EPA Section 608 Type II certification minimum
EXPERT RATIONALE: Federal and Nevada state law require technicians handling
refrigerants to maintain at least EPA Section 608 Type II certification (small
appliances and commercial equipment). Type I is for small appliances only, Type II
covers high-pressure appliances, and Type III covers low-pressure systems. Many
contractors require their technicians to hold universal Type III certification for
broader capability.
3. QUESTION: Which refrigerant is classified as a Class A1 non-toxic, non-
flammable substance?
A) R-410A
B) R-404A
C) R-22
D) R-290 (propane)
E) R-717 (ammonia)
CORRECT ANSWER: A) R-410A
,EXPERT RATIONALE: R-410A is classified as Class A1, indicating it is non-toxic and
non-flammable, making it safe for residential and commercial applications. R-22 is
an HCFC being phased out due to ozone depletion. R-290 and R-717 are flammable
and toxic respectively. R-404A is a safer alternative but not Class A1.
4. QUESTION: What is the maximum allowable pressure drop in a residential
air conditioning refrigerant line set?
A) 0.5 PSI per 100 feet
B) 2 PSI per 100 feet
C) 5 PSI per 100 feet
D) 10 PSI per 100 feet
E) 15 PSI per 100 feet
CORRECT ANSWER: B) 2 PSI per 100 feet
EXPERT RATIONALE: Industry standards and Nevada code requirements specify
that pressure drop in refrigerant lines should not exceed 2 PSI per 100 feet of line
length. Excessive pressure drop reduces system efficiency, increases compressor
load, and shortens system lifespan. Proper line sizing and installation prevent these
issues.
5. QUESTION: Which type of thermostat control is required for modern
energy-efficient commercial air conditioning systems in Nevada?
A) Mercury bulb thermostat only
B) Programmable or smart thermostat with setpoint control
C) Manual on-off switch
D) Mechanical expansion valve control
E) Pressure-actuated control valve
, CORRECT ANSWER: B) Programmable or smart thermostat with setpoint
control
EXPERT RATIONALE: Nevada building codes and energy efficiency standards now
require programmable thermostats that allow temperature setpoint control,
occupancy scheduling, and demand-controlled ventilation in commercial buildings.
This improves energy efficiency and meets state compliance requirements.
6. QUESTION: What is the proper procedure for evacuating an air conditioning
system before refrigerant recovery?
A) Quickly open all connections to release pressure
B) Use a vacuum pump to pull system pressure below 500 microns
C) Vent refrigerant to the atmosphere using a recovery line
D) Flush the system with nitrogen gas at high pressure
E) Disconnect hoses and allow system to naturally depressurize
CORRECT ANSWER: B) Use a vacuum pump to pull system pressure below 500
microns
EXPERT RATIONALE: Proper evacuation removes non-condensable gases and
moisture from the system, which is critical for system reliability and longevity. EPA
regulations prohibit venting refrigerants. A vacuum pump must reduce system
pressure to below 500 microns of mercury for adequate evacuation, ensuring
system integrity.
7. QUESTION: Which component is responsible for metering refrigerant flow
into the evaporator coil?
A) Accumulator
B) Condenser
C) Expansion device (TXV or capillary tube)
