NATE Gas Furnace Service Practice Test

70 questions available

Build your confidence for NATE Gas Furnace Service. Practice the concepts, understand the answers, and strengthen your knowledge one question at a time.

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Certification exam
100 Exam questions
Your practice
70 Practice questions
1 hour 10 minutes Practice Time
Try 5 free questions
No account needed. A free account includes 20 questions for this exam.
The bar to clear Percentage (70% passing for most exams) Published passing score for this certification.
Official objectives from HVAC Licensing
HVAC Licensing70 practice questionsBank updated 2026-06-09
Blueprint verifiedChecked against HVAC Licensing official objectivesMetadata verified 2026-06-09How we verify

Exam overview and details

This NATE Gas Furnace Service Practice Test is a comprehensive, 70-question assessment designed to prepare HVAC professionals for the North American Technician Excellence (NATE) certification exam. NATE certification is the industry gold standard, recognized across the United States and Canada as a benchmark of technical competence and professionalism. This practice test covers the full scope of the official NATE exam blueprint, including Air Conditioning and Cooling, Air Distribution and Ventilation, Business and Law (for contractor exams), EPA 608 Refrigerant Handling, Electrical Theory and Controls, Heating Systems (gas, oil, electric, heat pumps), Load Calculations and System Sizing, Refrigeration Fundamentals and Cycle Theory, Safety and OSHA, and Troubleshooting and Diagnostics. Each question is crafted to mirror the rigor and format of the actual exam, testing both theoretical knowledge and practical application. Successfully passing the NATE exam demonstrates to employers, customers, and regulatory bodies that you possess the skills to install, maintain, and service gas furnaces and related HVAC systems safely and efficiently. This practice test is an essential tool for identifying knowledge gaps, building confidence, and ensuring you are exam-ready. It is suitable for experienced technicians seeking recertification, as well as those pursuing initial NATE certification to advance their careers in the HVAC industry.

Sample Questions

Choose an answer and explore the explanation to see how practice works.

Applied Knowledge

A 100,000 BTUH natural gas furnace is rated 80% AFUE. What is the approximate output heating capacity the technician should expect under steady-state operation?

Combustion and Venting

A 1980s vintage 80% furnace with a standing pilot has been retrofitted with a vent damper. The homeowner reports occasional pilot outages on windy days and a "rotten egg" smell when the damper is closed. The thermocouple tests good. What is the most likely interaction causing the symptom?

Electrical Controls

A service call reports "no heat and the furnace makes a humming noise then trips the breaker." The technician finds the blower motor (PSC) hums but does not start when 120V is applied directly to the motor leads. Capacitor terminals show 12.4 F on a 10 F rated capacitor. What is the correct diagnosis?

Service

A technician tests a flame rollout switch on a furnace that has tripped. The switch is a manual-reset 200F bimetal type. The heat exchanger shows no visible cracks or soot. What is the most common cause of rollout switch tripping on an 80% furnace?

Preventive Maintenance

A technician is performing a planned maintenance inspection and measures the hot surface igniter current draw at 4.8 A during the warm-up phase on a 120V circuit. The typical specification for this style igniter is 3.0-5.0 A at 120V. After 17 seconds the gas valve opens and flame is established. What conclusion follows?

Career Opportunities & Salary

Median salary: $61,010– Heating, Air Conditioning, and Refrigeration Mechanics and Installers

Source: BLS Occupational Employment and Wage Statistics, May 2025 -- Heating, Air Conditioning, and Refrigeration Mechanics and Installers (SOC 49-9021), US national. Occupation median, not a certification salary. (2025)

Heating, Air Conditioning, and Refrigeration Mechanics and Installers

Exam insights and study advice

Achieving NATE certification is a powerful career accelerator. It is the only HVAC certification that is nationally recognized and supported by the entire industry, including manufacturers, contractors, and utilities. Holding a NATE badge signals to employers that you are a top-tier technician committed to excellence, often leading to higher pay, better job opportunities, and increased job security. For contractors, NATE-certified technicians can command higher service rates and improve customer trust, as certification is a proven indicator of quality workmanship. This practice test directly supports your journey to earning that credential, helping you validate your expertise and stand out in a competitive market. In an industry where technology and regulations constantly evolve, NATE certification also demonstrates your commitment to ongoing professional development and adherence to the highest safety and performance standards.

What this exam covers

01Air Conditioning and Cooling

02Air Distribution and Ventilation

03Business and Law (for contractor exams)

04Electrical Theory and Controls

05EPA 608 Refrigerant Handling

06Heating Systems (gas, oil, electric, heat pumps)

07Load Calculations and System Sizing

08Refrigeration Fundamentals and Cycle Theory

09Safety and OSHA

10Troubleshooting and Diagnostics

Exam Details NATE-GFS | $120 USD

Exam Code NATE-GFS
Vendor HVAC Licensing
Exam Cost $120 USD
Passing Score Percentage (70% passing for most exams)
Exam questions 100
Question TypesMultiple Choice
Online Proctoring Available

Frequently Asked Questions

How many questions are on the actual NATE Gas Furnace Service exam, and how does this practice test compare?

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Can I use this practice test for NATE recertification?

What score do I need to pass the NATE Gas Furnace Service exam?

Are there any prerequisites for taking the NATE Gas Furnace Service exam?