ICC Journeyman Mechanical - G31-N Exam Prep Guide

The ICC Journeyman Mechanical - G31-N examination is designed for mechanical trade professionals preparing to demonstrate their knowledge of heating, cooling, ventilation, exhaust systems, duct construction, equipment installation, combustion air, fuel-gas systems, chimneys, vents, refrigeration, hydronic systems, and mechanical safety.

The ICC Journeyman Mechanical - G31-N exam prep collection includes a books and courses rental package, professionally highlighted and tabbed books, flexible online exam preparation, and a standard exam book package.

This guide explains the available study options, current examination details, reference books, major mechanical subjects, code-navigation methods, and practical preparation strategies.

Available G31-N Exam Prep Packages

• ICC Journeyman Mechanical - G31-N - Books & Courses Rental Package: $790.00 sale price, reduced from $1,090.00
• ICC Journeyman Mechanical - G31-N Highlighted & Tabbed Book Package: $495.00 sale price, reduced from $695.00
• ICC Journeyman Mechanical - G31-N - Online Exam Prep: $295.00 sale price, reduced from $395.00
• ICC Journeyman Mechanical - G31-N Exam Book Package: $345.00 sale price, reduced from $445.00

The rental package combines temporary book access with online preparation. The highlighted and tabbed package supports faster code navigation. The online course is suitable for candidates who already own the correct references, while the exam book package supports independent study.

Books & Courses Rental Package

The ICC Journeyman Mechanical - G31-N Books & Courses Rental Package combines access to the assigned mechanical and fuel-gas references with structured online exam preparation.

The package is listed at a sale price of $790.00, reduced from the regular price of $1,090.00.

This package may be appropriate for candidates who:

• Need the exam books and online course together
• Do not currently own the approved references
• Want an organized journeyman mechanical study plan
• Need help navigating two separate code books
• Want practice with mechanical calculations and code questions
• Prefer combining lessons, books, and exam-style practice

Candidates should review the current product listing for the rental period, course-access period, deposit requirements, shipping details, and return instructions.

Highlighted & Tabbed Book Package

The ICC Journeyman Mechanical - G31-N Highlighted & Tabbed Book Package provides professionally organized references for candidates who want to begin studying without preparing every section themselves.

The package is listed at a sale price of $495.00, reduced from the regular price of $695.00.

The highlighted and tabbed books may help candidates locate:

• General mechanical requirements
• Equipment and appliance provisions
• Ventilation and exhaust requirements
• Duct construction and installation
• Combustion-air methods
• Chimneys and vents
• Fuel-gas piping and sizing
• Refrigeration and hydronic systems

Prepared books can improve navigation, but candidates must still understand how to interpret and apply the requirements they locate.

Online Exam Prep

The ICC Journeyman Mechanical - G31-N Online Exam Prep course provides flexible, self-paced preparation for candidates who already own the correct references or plan to purchase them separately.

The course is listed at a sale price of $295.00, reduced from the regular price of $395.00.

Online preparation may help candidates:

• Review mechanical subjects in an organized order
• Understand how the two code books work together
• Practice equipment, duct, ventilation, and fuel-gas questions
• Improve code-book navigation
• Identify weak knowledge areas
• Complete exam-style practice questions
• Study around an active work schedule

Exam Book Package

The ICC Journeyman Mechanical - G31-N Exam Book Package provides the printed references associated with the examination for independent preparation.

The package is listed at a sale price of $345.00, reduced from the regular price of $445.00.

This package may be appropriate for candidates who:

• Prefer independent book-based study
• Want to own the exam references
• Already understand many mechanical trade subjects
• Want to create a personalized tab and highlighting system
• Already have separate training or practice questions
• Need the code books for continued professional use

What Is the ICC G31-N Examination?

The G31-N examination is associated with the ICC National Standard Journeyman Mechanical Contractor and Trades examination path. Participating jurisdictions may use it as part of a journeyman mechanical, HVAC, or mechanical contractor qualification process.

The examination currently includes 50 multiple-choice questions with a three-hour time limit.

The test is open book, subject to current ICC rules for approved references, permanent tabs, highlighting, handwritten notes, inserted materials, and book condition.

Most ICC Contractor and Trades examinations require at least 70 percent correct, but candidates should confirm the passing requirement through the applicable licensing authority and examination bulletin.

Passing G31-N does not automatically issue a license. The licensing authority controls experience, applications, insurance, registration, fees, and final approval.

G31-N Exam References

The current G31-N package identifies two primary references:

• International Mechanical Code, 2018 Edition
• International Fuel Gas Code, 2018 Edition

The International Mechanical Code supports preparation involving mechanical equipment, ventilation, exhaust systems, duct systems, combustion air, chimneys, vents, refrigeration, boilers, water heaters, hydronic piping, and mechanical safety.

The International Fuel Gas Code supports preparation involving fuel-gas piping, pipe sizing, valves, regulators, appliance installation, combustion air, chimneys, vents, connectors, testing, and fuel-gas safety.

Candidates should confirm the required editions before purchasing materials or scheduling the examination.

How the Two References Work Together

• Use the International Mechanical Code for heating, cooling, ventilation, exhaust, ductwork, refrigeration, boilers, hydronic systems, and general mechanical equipment.
• Use the International Fuel Gas Code for gas piping, gas pressure, appliance fuel connections, regulators, combustion air, chimneys, vents, and fuel-gas testing.

Some appliance questions may involve both references. Candidates should identify whether the question focuses on the mechanical equipment or the fuel-gas supply and venting system.

Confirm Local Licensing Requirements

Before purchasing materials or scheduling the examination, candidates should verify:

• Whether the licensing authority accepts G31-N
• The scope of the journeyman mechanical classification
• The required mechanical and fuel-gas code editions
• The current approved reference list
• The examination format and passing requirement
• Rules for tabs, highlighting, and notes
• Required HVAC or mechanical work experience
• Application and examination fees
• Required supervision
• Insurance or contractor-registration requirements
• License renewal requirements

What Does a Journeyman Mechanical Professional Do?

A journeyman mechanical professional installs, alters, repairs, maintains, and tests mechanical systems within the scope permitted by the applicable license.

Common responsibilities may include:

• Reading mechanical plans and equipment schedules
• Installing heating and cooling equipment
• Installing supply, return, and exhaust duct systems
• Installing ventilation equipment
• Connecting fuel-gas piping and appliances
• Installing chimneys, vents, and vent connectors
• Installing refrigeration piping and equipment
• Installing hydronic heating systems
• Testing equipment and controls
• Coordinating permits and inspections
• Troubleshooting mechanical systems
• Following jobsite and combustion safety requirements

Common G31-N Study Areas

• General mechanical regulations
• Mechanical equipment and appliances
• Equipment access and clearances
• Ventilation systems
• Exhaust systems
• Duct construction and installation
• Combustion air
• Chimneys and vents
• Fuel-gas piping and sizing
• Valves and regulators
• Boilers and water heaters
• Hydronic piping
• Refrigeration systems
• Special mechanical systems
• Electrical requirements connected to mechanical work
• Testing, inspection, and safety

General Mechanical Requirements

General mechanical provisions establish basic requirements for equipment installation, access, structural support, protection, and safe operation.

Study subjects may include:

• Equipment listing and labeling
• Manufacturer installation instructions
• Required permits and inspections
• Equipment access
• Working clearances
• Protection from physical damage
• Outdoor equipment installation
• Equipment in garages
• Rooftop equipment
• Condensate disposal
• Structural support
• Flood-hazard protection

Mechanical Equipment and Appliances

Candidates should understand the installation requirements for common heating, cooling, and mechanical appliances.

Equipment may include:

• Furnaces
• Boilers
• Heat pumps
• Air-conditioning systems
• Unit heaters
• Roof-mounted equipment
• Water heaters
• Commercial cooking exhaust equipment
• Makeup-air equipment
• Refrigeration equipment
• Solid-fuel appliances

Important considerations include clearances, access, combustion air, venting, electrical connections, condensate disposal, and manufacturer instructions.

Equipment Access and Service Space

Mechanical equipment must remain accessible for inspection, service, repair, and replacement.

Candidates should review:

• Working space around equipment
• Access openings
• Attic access
• Crawl-space access
• Rooftop access
• Service platforms
• Walkways
• Lighting and receptacles
• Protection near roof edges
• Replacement paths

Ventilation Systems

Ventilation systems introduce outdoor air and remove contaminated or stale air from occupied spaces.

Study subjects may include:

• Natural ventilation
• Mechanical ventilation
• Outdoor-air requirements
• Occupancy-based ventilation rates
• Air-distribution requirements
• Air intakes
• Exhaust outlets
• Recirculation limitations
• Makeup air
• Controls and system operation
• Whole-building ventilation

Candidates should identify the occupancy and system type before calculating or selecting the required airflow.

Mechanical Exhaust Systems

Mechanical exhaust systems remove heat, moisture, odors, smoke, grease, fumes, and other contaminants.

Common exhaust applications include:

• Bathrooms and toilet rooms
• Clothes dryers
• Domestic kitchens
• Commercial kitchens
• Parking garages
• Hazardous exhaust systems
• Paint and finishing areas
• Laboratories
• Dust-producing operations
• Equipment rooms

Study requirements may include airflow, duct materials, termination locations, makeup air, fire protection, and separation from other systems.

Commercial Kitchen Exhaust

Commercial kitchen systems may include hoods, grease ducts, exhaust fans, makeup air, fire-suppression systems, and required clearances.

Candidates should review:

• Type I and Type II hoods
• Grease duct construction
• Grease duct clearances
• Welded joints
• Access openings
• Exhaust fan installation
• Makeup-air systems
• Hood overhang and capture
• Fire suppression coordination
• Exhaust termination

Duct Systems

Duct systems distribute conditioned, ventilation, makeup, and exhaust air throughout a building.

Important study subjects include:

• Duct materials
• Flexible ducts and connectors
• Joints and seams
• Duct support
• Duct insulation
• Protection from damage
• Underground ducts
• Plenums
• Air filters
• Fire and smoke dampers
• Return-air limitations
• Duct penetrations

Duct Construction and Support

Ducts must be constructed and supported to maintain airflow, limit leakage, and prevent excessive movement or collapse.

Preparation may include:

• Sheet-metal thickness
• Transverse and longitudinal joints
• Flexible duct length
• Support spacing
• Protection from crushing
• Hangers and straps
• Sealing requirements
• Insulation and vapor retarders
• Access for cleaning
• Manufacturer installation requirements

Fire and Smoke Dampers

Dampers help protect rated assemblies and control the movement of fire and smoke through duct systems.

Study subjects may include:

• Fire dampers
• Smoke dampers
• Combination fire-smoke dampers
• Ceiling radiation dampers
• Required locations
• Access doors
• Installation orientation
• Actuation and controls
• Inspection and testing
• Exceptions for certain penetrations

Combustion Air

Fuel-burning appliances require sufficient air for combustion, ventilation, and dilution of flue gases.

Combustion-air requirements may depend on:

• Total appliance input
• Room volume
• Building construction
• Indoor openings
• Outdoor openings
• Horizontal or vertical ducts
• Mechanical combustion air
• Louver and grille free area
• Competing exhaust systems
• Appliance type

Candidates should identify the combustion-air method before calculating required openings or airflow.

Chimneys and Vents

Chimneys and vents carry combustion products safely outdoors.

Important preparation subjects include:

• Masonry chimneys
• Factory-built chimneys
• Type B gas vents
• Special gas vents
• Vent connectors
• Common venting
• Vent sizing
• Clearance to combustibles
• Vent support and slope
• Termination requirements
• Condensing appliances
• Manufacturer instructions

Fuel-Gas Piping

Fuel-gas piping must deliver sufficient gas to connected appliances while maintaining the required operating pressure.

Study subjects may include:

• Natural gas and propane
• Connected appliance demand
• Pipe-sizing tables
• Developed length
• Steel piping
• Corrugated stainless steel tubing
• Underground plastic piping
• Joints and fittings
• Pipe support
• Corrosion protection
• Pressure testing
• Leak detection

Gas Pipe-Sizing Calculations

Gas pipe sizing may depend on fuel type, pressure, permitted pressure drop, pipe material, system length, and connected demand.

A practical sizing process includes:

• List all connected appliances
• Determine each appliance input rating
• Calculate the demand carried by each pipe section
• Determine the required developed length
• Select the correct fuel, pressure, and material table
• Choose a pipe size with sufficient capacity

Candidates should avoid mixing natural gas, propane, low-pressure, and elevated-pressure sizing tables.

Gas Valves and Regulators

Valves and regulators control gas flow and protect appliances from improper pressure.

Candidates should review:

• Building shutoff valves
• Appliance shutoff valves
• Line pressure regulators
• Appliance regulators
• Regulator capacity
• Regulator venting
• Overpressure protection
• Valve accessibility
• Appliance connectors
• Sediment traps

Boilers and Hydronic Systems

Boilers and hydronic systems use heated water or another fluid to transfer energy through piping and terminal equipment.

Study subjects may include:

• Boiler location and clearances
• Safety and relief valves
• Expansion tanks
• Low-water cutoffs
• Pressure controls
• Hydronic piping materials
• Circulating pumps
• Air removal
• System fill and makeup water
• Testing
• Combustion air
• Chimneys and vents

Refrigeration Systems

Refrigeration requirements address equipment, piping, machinery rooms, refrigerant quantities, ventilation, safety controls, and system testing.

Candidates should review:

• Refrigerant classifications
• System classification
• Refrigerant quantity limitations
• Refrigeration piping
• Pressure testing
• Machinery rooms
• Mechanical ventilation
• Refrigerant detection
• Pressure-relief devices
• Emergency controls
• Equipment access
• System identification

Mechanical and Fuel-Gas Testing

Mechanical systems and gas piping may require inspection and testing before concealment or operation.

Study areas may include:

• Gas piping pressure tests
• Approved test media
• Gauge selection
• Leak detection
• Refrigeration pressure tests
• Duct leakage testing
• System balancing
• Equipment startup
• Combustion testing
• Inspection documentation
• Repair and retesting

Electrical Requirements for Mechanical Work

Mechanical equipment commonly requires electrical power, disconnecting means, controls, grounding, and service receptacles.

Journeyman mechanical candidates may need to recognize requirements involving:

• Equipment disconnects
• Service receptacles
• Equipment grounding
• Overcurrent protection
• Motor controllers
• Low-voltage controls
• Emergency shutoff switches
• Working clearances
• Wiring protection near equipment

Electrical work must be performed within the scope allowed by the applicable trade licenses and local regulations.

Mechanical Calculations

G31-N preparation may include basic calculations and table interpretation.

Common calculation subjects may include:

• Ventilation airflow
• Exhaust airflow
• Combustion-air openings
• Duct dimensions and areas
• Gas appliance demand
• Gas pipe sizing
• Hydronic system capacity
• Refrigerant quantity limits
• Equipment clearance measurements
• Unit conversions

Candidates should identify the units requested and write each calculation step clearly.

Code-Book Navigation

An open-book examination still requires fast and accurate reference navigation.

A practical lookup method includes:

• Read the complete question
• Identify whether it concerns mechanical equipment or fuel gas
• Select the International Mechanical Code or International Fuel Gas Code
• Use the index or table of contents
• Locate the complete section, table, or figure
• Review definitions, exceptions, and footnotes
• Confirm that the requirement applies to the stated system
• Record difficult subjects for additional practice

Recommended Study Plan

• Review exam rules and reference-book organization
• Study general mechanical requirements
• Review equipment access and clearances
• Study ventilation and exhaust systems
• Review duct construction and fire dampers
• Practice combustion-air calculations
• Study chimneys and venting
• Practice gas pipe-sizing questions
• Review boilers and hydronic systems
• Study refrigeration systems
• Review testing and safety requirements
• Complete timed code-navigation exercises
• Review every missed practice question

Which G31-N Package Should You Choose?

• Choose the Books & Courses Rental Package for temporary access to both references and structured online preparation.
• Choose the Highlighted & Tabbed Book Package for professionally organized books designed to support faster navigation.
• Choose Online Exam Prep when you already own the correct references and want guided study.
• Choose the Exam Book Package for independent preparation and permanent book ownership.

FAQ

Q. What is the ICC Journeyman Mechanical - G31-N exam?

A. It is an ICC Contractor and Trades examination used by participating jurisdictions to evaluate journeyman-level mechanical, HVAC, ventilation, duct, fuel-gas, refrigeration, and safety knowledge.

Q. How much does the Books & Courses Rental Package cost?

A. The sale price is $790.00, reduced from the regular price of $1,090.00.

Q. How much does the Highlighted & Tabbed Book Package cost?

A. The sale price is $495.00, reduced from the regular price of $695.00.

Q. How much does Online Exam Prep cost?

A. The sale price is $295.00, reduced from the regular price of $395.00.

Q. How much does the Exam Book Package cost?

A. The sale price is $345.00, reduced from the regular price of $445.00.

Q. What books are included in the G31-N Exam Book Package?

A. The current package includes the 2018 International Mechanical Code and 2018 International Fuel Gas Code.

Q. How many questions are on the G31-N examination?

A. The examination currently includes 50 multiple-choice questions.

Q. How much time is allowed?

A. Candidates currently have three hours to complete the examination.

Q. Is the G31-N examination open book?

A. Yes. Candidates may use approved references subject to current ICC testing rules.

Q. What score is required to pass?

A. Most ICC Contractor and Trades examinations require 70 percent correct, but candidates should confirm the applicable requirement before testing.

Q. What subjects should I study?

A. Study mechanical equipment, ventilation, exhaust, duct systems, combustion air, chimneys, vents, gas piping, boilers, hydronic systems, refrigeration, testing, and safety.

Q. Should I practice gas pipe-sizing calculations?

A. Yes. Candidates should practice identifying appliance demand, developed length, fuel type, system pressure, and the correct sizing table.

Q. Should I study both mechanical and fuel-gas codes?

A. Yes. The examination uses both the International Mechanical Code and International Fuel Gas Code.

Q. Does passing G31-N automatically issue a mechanical license?

A. No. The applicable licensing authority controls experience, applications, supervision, insurance, fees, registration, and final approval.

Q. Where can I purchase the G31-N packages?

A. The available options can be found in the ICC Journeyman Mechanical - G31-N exam prep collection.

Conclusion

The ICC Journeyman Mechanical - G31-N examination requires candidates to combine practical mechanical trade experience with efficient navigation of the International Mechanical Code and International Fuel Gas Code.

Important preparation subjects include mechanical equipment, ventilation, exhaust systems, duct construction, combustion air, chimneys, vents, fuel-gas piping, boilers, hydronic systems, refrigeration, testing, and safety.

1 Exam Prep offers a Books & Courses Rental Package, Highlighted & Tabbed Book Package, Online Exam Prep, and Exam Book Package for different preparation needs and budgets.

Shop ICC Journeyman Mechanical - G31-N Exam Prep

Key Takeaways

• G31-N is the ICC National Standard Journeyman Mechanical examination path.
• The Books & Courses Rental Package sale price is $790.00.
• The Highlighted & Tabbed Book Package sale price is $495.00.
• The Online Exam Prep sale price is $295.00.
• The Exam Book Package sale price is $345.00.
• The exam currently includes 50 questions and a three-hour limit.
• The examination is open book under current testing rules.
• The references are the 2018 International Mechanical Code and 2018 International Fuel Gas Code.
• Major subjects include equipment, ventilation, exhaust, ducts, combustion air, venting, fuel gas, boilers, and refrigeration.
• Passing G31-N does not automatically issue a mechanical license.
• Candidates should verify current exam and jurisdictional requirements before registering.