Refrigerants & Environmental Regulations
Refrigerant types, ODP, GWP, azeotropic and zeotropic blends, temperature glide, and charging methods.
- Classify refrigerants by type - CFC, HCFC, HFC, and natural
- Explain ODP and GWP values and their regulatory significance
- Compare azeotropic and zeotropic blends including temperature glide
- Describe proper charging methods for different refrigerant types
Lección 1
CFC, HCFC, HFC & Natural Refrigerants
Refrigerant Classification
Refrigerants are classified by their chemical composition and environmental impact. The Red Seal exam expects you to know which refrigerants fall into each category and their regulatory status in Canada.
CFC (Chlorofluorocarbons)
Examples: R-11, R-12, R-502
ODP: High (contains chlorine)
Status: Production banned since 1996
Numbering: 400/500 series blends
HCFC (Hydrochlorofluorocarbons)
Examples: R-22, R-123, R-141b
ODP: Low (reduced chlorine)
Status: Production banned since 2020
Note: Transitional refrigerants
HFC (Hydrofluorocarbons)
Examples: R-134a, R-404A, R-410A
ODP: Zero (no chlorine)
Status: Currently in use, GWP regulated
Note: Phase-down under Kigali Amendment
Natural Refrigerants
Natural refrigerants are substances that occur in nature. They have zero ODP and very low GWP. The most common natural refrigerants are:
- R-717 (Ammonia) - Used in industrial refrigeration, highly efficient but toxic and flammable
- R-744 (CO2) - Used in transcritical systems and cascade systems, very high operating pressures
- R-290 (Propane) - Used in small commercial units, flammable (A3 safety classification)
- R-600a (Isobutane) - Used in domestic refrigerators, flammable
Safety Classification
Ammonia (R-717) is classified as B2L - toxic and mildly flammable. Propane (R-290) is A3 - non-toxic but highly flammable. The exam tests safety classifications and their implications for system design.
CFCs (R-12) are banned and have high ODP. HCFCs (R-22) are banned and have low ODP. HFCs (R-134a, R-410A) have zero ODP but high GWP. Natural refrigerants (ammonia, CO2, propane) have zero ODP and very low GWP.