Refrigerants & Lubricants
Refrigerant properties, classifications, handling, recovery, ammonia systems, oil separators, and charging procedures.
- Classify refrigerant types and their properties
- Describe ammonia and special refrigerant characteristics
- Explain proper oil selection, charging procedures, and recovery requirements
Lesson 1
Refrigerant Types & Properties
Refrigerant Classification
Refrigerants are classified by their chemical composition and assigned an R-number designation. Understanding these classifications is critical for the Red Seal exam.
CFCs (Chlorofluorocarbons)
Banned - highest ozone depletion
R-11, R-12 (Freon)
No longer manufactured
ODP = 1.0 (reference)
HCFCs (Partial chlorine)
Phase-out in progress
R-22 (most common HCFC)
Lower ODP than CFCs
Still found in older systems
HFCs (No chlorine)
Being phased down
R-134a, R-410A, R-404A
Zero ODP
High GWP - subject to global phasedown schedules
HFOs & A2L Blends (Low-GWP)
New equipment standard
R-454B (GWP 466), R-32 (GWP 675), R-1234yf
Zero ODP, low GWP
A2L classification - mildly flammable
Key Properties
| Property | Definition | Significance |
|---|---|---|
| ODP (Ozone Depletion Potential) | Damage to ozone layer | Higher = worse for ozone |
| GWP (Global Warming Potential) | Greenhouse effect | Higher = worse for climate |
| Boiling point | Temperature at atmospheric pressure | Determines application range |
| Flammability | ASHRAE safety classification | A1 = safest, B3 = most hazardous |
| Toxicity | Health effects of exposure | A = low toxicity, B = higher toxicity |
ASHRAE Safety Classifications
Refrigerants are classified by toxicity (A or B) and flammability (1, 2L, 2, or 3):
- A1 - low toxicity, no flame propagation (R-134a, R-410A)
- A2L - low toxicity, mildly flammable (R-32, R-1234yf)
- B1 - higher toxicity, no flame propagation (R-123)
- B2L - higher toxicity, mildly flammable (R-717 ammonia)
R-410A to A2L Transition
R-410A (GWP 2,088) replaced R-22 in most systems but is now itself being phased down under Canada's HFC phasedown schedule (aligned with the Kigali Amendment to the Montreal Protocol). New residential and light commercial equipment is transitioning to lower-GWP A2L refrigerants such as R-454B (GWP 466) and R-32 (GWP 675). These A2L refrigerants are mildly flammable and require updated service procedures and equipment designed for A2L use.
Canada HFC Phasedown
Canada's HFC phasedown is implemented under the Ozone-Depleting Substances and Halocarbon Alternatives Regulations (ODSHAR), aligned with the Kigali Amendment to the Montreal Protocol. The phasedown reduces allowable HFC production and consumption progressively to 85% by the mid-2030s. This directly affects R-410A availability and cost for service work on existing systems.
Key implications for Red Seal candidates:
- R-410A is still used in existing systems and will be serviced for years to come
- New equipment installations now use A2L refrigerants (R-454B, R-32) in place of R-410A
- A2L refrigerants require ASHRAE 34 A2L-compliant installation practices due to mild flammability
- The transition mirrors the earlier R-22 to R-410A shift but with additional safety considerations
CFCs are banned, HCFCs (R-22) are phased out, and HFCs (R-410A, R-404A) are being phased down due to high GWP under Canada's ODSHAR regulations. New equipment uses lower-GWP A2L refrigerants such as R-454B and R-32. Know the ASHRAE safety classification system - A1 is the safest, A2L is mildly flammable (new standard for new equipment).