Section 1: Refrigerants, Gases and Oils

General Learning Outcomes

Upon completion, apprentices will be able to:

  • Define key terms (refrigerant, GWP/ODP, recovery/recycling/reclamation) and classify refrigerants per ASHRAE 34 (A1, A2L, etc.).
  • Identify hazards (frostbite, asphyxiation, flammability) and apply safe practices, PPE, and LOTO procedures.
  • Explain Canadian regulations covering ODS/halocarbons, TDG, 2026 phase-downs, and leak rules for systems above 10 kg.
  • Describe refrigerant types — HCFCs, HFCs phasing out, HFOs/A2L, and natural refrigerants such as R-744 — as well as blends and secondary fluids.
  • Outline recovery methods (liquid, push-pull, vapour) and associated tools (scales, manifolds, recovery units).
  • List HVAC gases, their uses, and safety requirements — for example, nitrogen purging and helium leak tests.
  • Select and discuss refrigerant oils (mineral oil, POE, PAG) for compatibility, handling, and storage.
  • Perform conversions, flushing, evacuation, and comply with storage and transport regulations.

Unit Overview

Unit 2: Introduction to Refrigerants & Handling Practices equips apprentices with essential knowledge on the fluids and lubricants used in refrigeration and air conditioning systems. It emphasizes safe practices, applicable regulations, and environmental responsibility — particularly in light of the 2026 HFC phase-downs requiring GWP below 750 for new residential equipment.

The five sections of this unit build progressively:

  • Section 1: Core terminology, hazards, codes, and refrigerant classifications.
  • Section 2: Refrigerant types (CFCs to HFOs) and recovery methods and tools.
  • Section 3: HVAC gases — nitrogen, acetylene, and others.
  • Section 4: Oils and lubricants — POE, PAG, vacuum pump oil, and others.
  • Section 5: Conversions, flushing, storage, and transport requirements.

Key Principles for This Unit

Throughout this unit, keep the following principles in mind:

  • Refrigerant venting to atmosphere is illegal in Canada and must never occur.
  • Always identify the refrigerant type before connecting any equipment or opening any system.
  • Use calibrated tools, approved cylinders, and rated hoses for every recovery, charging, or testing task.
  • Follow WHMIS requirements and consult the SDS for every chemical substance used.
  • Proper oil selection and moisture control are critical to system reliability and compressor life.
  • Transport of Dangerous Goods (TDG) regulations apply to refrigerants and gases — know the requirements before transporting cylinders.
  • Environmental responsibility is not optional — recover, recycle, and reclaim refrigerants to reduce GWP impact.