MISSOURI HVAC CONTRACTOR EXAM – QUESTIONS AND ANSWERS | VERIFIED AND WELL DETAILED
ANSWERS | PLUS RATIONALES | GUARANTEED PASS | LATEST EXAM UPDATE
Core Domains
1. Missouri Licensing Law and Local Jurisdiction Requirements
2. International Mechanical Code (IMC) and Local Amendments
3. International Fuel Gas Code (IFGC) and Gas Piping
4. Refrigeration Cycle, Theory, and EPA Regulations
5. Electrical Components, Motors, and National Electrical Code (NEC)
6. Load Calculations and Air Distribution Systems
7. Hydronic and Steam Heating Systems
8. Professional Business Practices, Safety, and Project Management
Introduction
This comprehensive examination is designed to rigorously assess the knowledge and practical skills required for
candidates pursuing the Missouri HVAC Contractor License. The test evaluates a candidate's understanding of
fundamental refrigeration theory, electrical components, system installation, and the application of EPA
regulations governing refrigerant handling. It emphasizes real-world decision-making, from troubleshooting
complex system failures to ensuring compliance with safety and environmental standards. The format includes
multiple-choice questions that challenge the installer to apply theory to practical situations, ensuring they are
prepared to deliver efficient, safe, and reliable heating and cooling solutions in residential and commercial
settings.
,SECTION ONE: QUESTIONS 1 – 100
1. The 588-MO-SL Commercial HVAC Servicer/Installer exam is administered by which authority in St. Louis
County?
A. Missouri Department of Labor
B. St. Louis County Department of Public Works
C. Board of Mechanical Examiners
D. OSHA
🟢C
🔴 Explanation: The correct answer is C. The St. Louis County Board of Mechanical Examiners administers the
exam, reviews applications, and issues the license. The Department of Public Works enforces compliance and
issues permits .
2. How many hours of continuing education are required every two years to maintain a St. Louis County
mechanical contractor license?
A. 8 hours
B. 12 hours
C. 16 hours
D. 24 hours
🟢B
🔴 Explanation: The correct answer is B. County ordinance mandates 12 hours of approved continuing
education for license renewal every two years .
3. What is the minimum passing score for the HVACR license examination in Poplar Bluff, Missouri?
A. 60%
,B. 65%
C. 70%
D. 75%
🟢C
🔴 Explanation: The correct answer is C. City code requires a grade of 70% as the lowest passing grade for
the examination .
4. In Poplar Bluff, a Class A mechanical installer license requires proof of how many years of experience in the
HVACR field?
A. 4 years
B. 6 years
C. 8 years
D. 10 years
🟢C
🔴 Explanation: The correct answer is C. A Class A license requires proof of eight years of experience. Class B
requires six years and Class C requires four years .
5. According to the Poplar Bluff HVACR code, what is the minimum bond amount required for an HVACR
licensee?
A. $1,000
B. $3,000
C. $5,000
D. $10,000
🟢B
, 🔴 Explanation: The correct answer is B. Each licensee must execute and deposit a bond in the amount of
$3,000.00 with the Building Inspector .
6. A Class B mechanical installer in Poplar Bluff is permitted to work on systems with what maximum cooling
capacity?
A. 5 tons per unit
B. 10 tons per unit
C. 15 tons per unit
D. 20 tons per unit
🟢C
🔴 Explanation: The correct answer is C. Class B licensees may perform work on air conditioning systems of
not more than 15 tons cooling capacity per unit or 1,000,000 BTUH heating input .
7. In St. Charles County, a Class "A" license entitles the licensee to perform mechanical work:
A. Only on systems under 5 tons
B. On systems up to 15 tons
C. Without limitation to all BTUH or horsepower capacities
D. Only on residential systems
🟢C
🔴 Explanation: The correct answer is C. Class "A" licenses entitle the licensee to perform Mechanical Work
without limitation to all BTUH or horsepower capacities .
8. For a St. Charles County Class "A" mechanical license, which ICC exam is accepted?
A. F31 or G31 (Journeyman Mechanical)
B. F29 or G29 (Master Mechanical)
ANSWERS | PLUS RATIONALES | GUARANTEED PASS | LATEST EXAM UPDATE
Core Domains
1. Missouri Licensing Law and Local Jurisdiction Requirements
2. International Mechanical Code (IMC) and Local Amendments
3. International Fuel Gas Code (IFGC) and Gas Piping
4. Refrigeration Cycle, Theory, and EPA Regulations
5. Electrical Components, Motors, and National Electrical Code (NEC)
6. Load Calculations and Air Distribution Systems
7. Hydronic and Steam Heating Systems
8. Professional Business Practices, Safety, and Project Management
Introduction
This comprehensive examination is designed to rigorously assess the knowledge and practical skills required for
candidates pursuing the Missouri HVAC Contractor License. The test evaluates a candidate's understanding of
fundamental refrigeration theory, electrical components, system installation, and the application of EPA
regulations governing refrigerant handling. It emphasizes real-world decision-making, from troubleshooting
complex system failures to ensuring compliance with safety and environmental standards. The format includes
multiple-choice questions that challenge the installer to apply theory to practical situations, ensuring they are
prepared to deliver efficient, safe, and reliable heating and cooling solutions in residential and commercial
settings.
,SECTION ONE: QUESTIONS 1 – 100
1. The 588-MO-SL Commercial HVAC Servicer/Installer exam is administered by which authority in St. Louis
County?
A. Missouri Department of Labor
B. St. Louis County Department of Public Works
C. Board of Mechanical Examiners
D. OSHA
🟢C
🔴 Explanation: The correct answer is C. The St. Louis County Board of Mechanical Examiners administers the
exam, reviews applications, and issues the license. The Department of Public Works enforces compliance and
issues permits .
2. How many hours of continuing education are required every two years to maintain a St. Louis County
mechanical contractor license?
A. 8 hours
B. 12 hours
C. 16 hours
D. 24 hours
🟢B
🔴 Explanation: The correct answer is B. County ordinance mandates 12 hours of approved continuing
education for license renewal every two years .
3. What is the minimum passing score for the HVACR license examination in Poplar Bluff, Missouri?
A. 60%
,B. 65%
C. 70%
D. 75%
🟢C
🔴 Explanation: The correct answer is C. City code requires a grade of 70% as the lowest passing grade for
the examination .
4. In Poplar Bluff, a Class A mechanical installer license requires proof of how many years of experience in the
HVACR field?
A. 4 years
B. 6 years
C. 8 years
D. 10 years
🟢C
🔴 Explanation: The correct answer is C. A Class A license requires proof of eight years of experience. Class B
requires six years and Class C requires four years .
5. According to the Poplar Bluff HVACR code, what is the minimum bond amount required for an HVACR
licensee?
A. $1,000
B. $3,000
C. $5,000
D. $10,000
🟢B
, 🔴 Explanation: The correct answer is B. Each licensee must execute and deposit a bond in the amount of
$3,000.00 with the Building Inspector .
6. A Class B mechanical installer in Poplar Bluff is permitted to work on systems with what maximum cooling
capacity?
A. 5 tons per unit
B. 10 tons per unit
C. 15 tons per unit
D. 20 tons per unit
🟢C
🔴 Explanation: The correct answer is C. Class B licensees may perform work on air conditioning systems of
not more than 15 tons cooling capacity per unit or 1,000,000 BTUH heating input .
7. In St. Charles County, a Class "A" license entitles the licensee to perform mechanical work:
A. Only on systems under 5 tons
B. On systems up to 15 tons
C. Without limitation to all BTUH or horsepower capacities
D. Only on residential systems
🟢C
🔴 Explanation: The correct answer is C. Class "A" licenses entitle the licensee to perform Mechanical Work
without limitation to all BTUH or horsepower capacities .
8. For a St. Charles County Class "A" mechanical license, which ICC exam is accepted?
A. F31 or G31 (Journeyman Mechanical)
B. F29 or G29 (Master Mechanical)
