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TSSA G2 Gas Trade Training Units

Advanced Gas Trade Training Units for TSSA G2 (Gas Technician 2 - Intermediate) certification. Comprehensive CSA B149.1-25 and B149.2-25 applications for independent gas technician work in Ontario.

⚠️ G2 Prerequisites Required

Before pursuing G2 certification, you must have:

📋 G2 Certification Requirements

10

Unit 10: Gas Meters and Regulators

Advanced gas measurement, metering, and pressure regulation systems - essential for complex installations and commercial work.

  • Meters and Measurement
  • Pressure Regulators - First and Second Stage
  • Regulator Applications and Installation
  • Regulator Venting and Safety Systems

CSA Code: B149.1-25 Section 5 (Gas Supply and Metering)

11

Unit 11: Pool Heaters and Boilers

Swimming pool heating systems, advanced boiler installations, and water heating applications for commercial settings.

  • Pool Heater Types and Installation
  • Pool Heater Safety and Controls
  • Boiler Classifications and Applications
  • Boiler Installation and Piping
  • Boiler Controls and Safety Devices

CSA Code: B149.1-25 Section 6 (Water Heating Equipment)

12

Unit 12: Forced Air Furnaces

Advanced forced air heating systems, furnace installation, airflow calculations, and ducting requirements per code.

  • Forced Air Heating Systems Components
  • Furnace Types and Efficiency Ratings
  • Installation and Clearance Requirements
  • Airflow and Temperature Rise Calculations
  • Ductwork Design and Installation

CSA Code: B149.1-25 Section 6 (Furnace Installation)

13

Unit 13: Controls

Advanced control systems, thermostats, safety interlocks, and troubleshooting for gas appliances and systems.

  • Gas Valves and Control Components
  • Thermostats and Temperature Controls
  • Limit Controls and Safety Devices
  • Advanced Control Circuits and Troubleshooting

CSA Code: B149.1-25 Section 3 (Control Systems)

14

Unit 14: Building as a System

Understanding building science, stack effect, depressurization, and building-appliance interactions for safe installations.

  • Key Components - Building Envelope and Heat Transfer
  • Gas Technician/Fitter Use of Building as a System
  • Assessment Tools for the Building as a System
  • Indoor Air Quality - Ventilation and Pollutant Control

CSA Code: B149.1-25 Section 7 (Venting in Building Context)

15

Unit 15: Storage Water Heaters

Advanced water heater sizing, installation, safety systems, and maintenance for residential and commercial applications.

  • Water Heater Types and Components
  • Sizing and Capacity Calculations
  • Installation Requirements and Clearances
  • Temperature and Pressure Relief Devices
  • Maintenance and Troubleshooting

CSA Code: B149.1-25 Section 6 (Water Heating Equipment)

16

Unit 16: Water Heaters - Direct Vent/Power Vent & Tankless

Advanced direct vent, power vent, and tankless water heater technologies, installations, and troubleshooting techniques.

  • Direct Vent Water Heaters - Design and Installation
  • Power Vent Systems and Components
  • Tankless Water Heaters - Operation and Sizing
  • Condensing Technology and Efficiency
  • Advanced Troubleshooting and Diagnostics

CSA Code: B149.1-25 Section 6, 7 (Vented Water Heating)

17

Unit 17: Ranges, Ovens & Cooktops

Gas cooking appliances, installation requirements, gas pressure adjustments, and safety systems for commercial settings.

  • Gas Ranges and Ovens - Types and Components
  • Cooktops and Built-In Units
  • Installation and Clearance Requirements
  • Pressure Adjustment and Conversion
  • Commercial Cooking Equipment

CSA Code: B149.1-25 Section 6 (Cooking Appliances)

18

Unit 18: Dryers, Conversions & Miscellaneous Appliances

Gas dryer installations, fuel conversions, and various specialty gas appliances for residential and commercial use.

  • Gas Dryers - Installation and Venting
  • Fuel Conversions - Natural Gas to Propane
  • Conversion Procedures and Adjustments
  • Miscellaneous Gas Appliances

CSA Code: B149.1-25 Section 6 (Dryers and Appliances)

19

Unit 19: Basic Hydronic Systems

Hydronic heating fundamentals, boiler systems, piping configurations, and water-based heating distribution systems.

  • Hydronic System Components and Operation
  • Boiler Types and Applications
  • Piping Configurations and Design
  • Circulators and System Controls
  • Expansion Tanks and Air Elimination

CSA Code: B149.1-25 Section 6 (Hydronic Equipment)

20

Unit 20: Basic Radiant Heating Systems

Radiant heating design, installation, controls, and applications for residential and commercial comfort heating.

  • Radiant Heating Principles and Benefits
  • Radiant System Types - Floor, Wall, Ceiling
  • Design and Layout Considerations
  • Controls and Zone Management
  • Installation Requirements and Best Practices

CSA Code: B149.1-25 Section 6 (Radiant Heating)

21

Unit 21: Space Heaters and Fireplaces

Gas fireplaces, space heaters, unit heaters, and decorative appliances - installation, venting, and safety requirements.

  • Gas Fireplaces - Types and Installation
  • Vented and Vent-Free Space Heaters
  • Unit Heaters - Suspended and Floor Models
  • Decorative Gas Appliances
  • Clearances and Safety Requirements

CSA Code: B149.1-25 Section 6 (Space Heating)

22

Unit 22: Venting Systems

Advanced venting design, vent sizing calculations, Category I-IV appliances, and combustion air requirements - heavily tested.

  • Venting Systems - Types and Materials
  • Vent Installation and Assembly
  • Vent Design for Category I Appliances
  • Size Venting Systems for Category I Appliances
  • Vent Inspection and Troubleshooting
  • Air Requirements - Combustion and Ventilation

CSA Code: B149.1-25 Section 7 (Venting and Combustion Air)

23

Unit 23: Indoor Air Quality (Forced Air Add-Ons)

Air filters, humidifiers, cooling coils, and IAQ equipment integration with forced air gas heating systems.

  • Air Filters and Cleaners - Types and MERV Ratings
  • Humidifiers - Installation and Water Supply
  • Cooling Coils - Integration with Gas Systems

CSA Code: B149.1-25 Section 7 (Ventilation and Air Quality)

24

Unit 24: Heat Loss/Heat Gain & Air Handling Units

Load calculations, heat loss/gain methods, appliance sizing, and air handling unit operations - final G2 unit.

  • Heat Loss/Heat Gain - Calculation Methods
  • Air Handling Units - Components and Operation

CSA Code: B149.1-25 Section 9 (Appliance Sizing)

💡 Building on G3 Foundation

G2 training builds directly on Gas Trade Units 1-9 from G3 certification. Make sure you have strong understanding of:

Review G3 Units →

📚 Recommended G2 Study Path

  1. Start with Unit 10: Gas Meters and Regulators - Foundation of advanced gas supply systems.
  2. Progress to Unit 22: Venting Systems - Most heavily tested unit, critical for all installations.
  3. Study Unit 14: Building as a System - Understanding building science prevents common problems.
  4. Complete Unit 12: Forced Air Furnaces - Core residential installation knowledge.
  5. Learn Unit 13: Controls - Essential for troubleshooting and advanced work.
  6. Study Units 15-16: Water Heaters - Common service and installation work.
  7. Complete Units 19-20: Hydronic and Radiant - Specialized heating systems.
  8. Finish Units 17-18, 21, 23-24 - Round out your knowledge with specialty appliances and calculations.
  9. Take Practice Exams Regularly - Test knowledge with chapter reviews and unit exams.
  10. Review CSA B149.1-25 Throughout - Use Code Compass for specific code sections.
  11. Complete TSSA-Accredited Program - Required formal training for exam eligibility.

🚀 Ready for Advanced G2 Training?

Start with Unit 10 → Study Full CSA B149.1-25 Code → Launch AI Tutor (G2 Mode) →

📚 Additional G2 Study Resources

⚠️ Independent Educational Content

Advanced CSA-Compliant Study Materials: This content is provided by LARK Labs as independent educational resources for TSSA G2 intermediate certification. Materials are based on CSA B149.1-25, CSA B149.2-25, and advanced Gas Trade Training curriculum. We are not affiliated with CSA Group or TSSA.

Supplementary Training: These advanced materials complement official TSSA-accredited G2 training programs but do not replace certified instruction. G2 certification requires completion of an approved training program, valid G3 certification, and documented field experience.

Code References: All code references are to CSA B149.1-25 (17th Edition, 2025) and CSA B149.2-25 (7th Edition, 2025). Always consult official published codes for authoritative information on complex installations.

Created by: Mike Kapin | 20 years field experience + 10 years teaching HVAC and Gas Trade programs at Fanshawe College