Study guide
9.4 The R-22 Phaseout, Retrofits, and the Move to Lower-GWP A2Ls
EPA 608 Technician Certification Exam
Track your progress as you read
Finished sections get a check mark.
1 Introduction to EPA 608 Certification
1.1 What EPA 608 Is and Who Needs It 1.2 Exam Format, Scoring, and Administration 1.3 How to Study for EPA 608
2 Regulations and the Clean Air Act
2.1 Clean Air Act Overview 2.2 Penalties and Enforcement 2.3 Montreal Protocol and International Agreements 2.4 AIM Act and HFC Phasedown Schedule 2.5 SNAP Program and Refrigerant Transitions
3 Refrigerants and Ozone Science
3.1 The Science of Ozone Depletion (ODP and GWP) 3.2 Refrigerant Classification, ASHRAE Numbering, and Safety Groups 3.3 Common Refrigerants: Properties, Applications, and Phaseout Status 3.4 Refrigerant Blends: Glide, Fractionation, and Liquid Charging
4 The Refrigeration Cycle
4.1 The Basic Refrigeration Cycle 4.2 System Components in Detail 4.3 Heat Transfer and Pressure-Temperature Relationships
5 Refrigerant Safety and Handling
5.1 Refrigerant Hazards and Health Effects 5.2 Safe Handling Practices, PPE, and Cylinders 5.3 A2L (Mildly Flammable) Refrigerant Safety
6 Recovery, Recycling, and Reclaiming
6.1 The Three Rs: Recover, Recycle, Reclaim 6.2 Recovery Equipment Requirements 6.3 Required Levels of Evacuation 6.4 Refrigerant Sales Restrictions and Recordkeeping
7 Leak Detection and Repair
7.1 Leak Detection Methods 7.2 Leak Repair Requirements and Trigger Rates 7.3 Leak-Rate Calculation, Recordkeeping, and Reporting
8 Type I — Small Appliances
8.1 What Counts as a Small Appliance 8.2 Type I Recovery Requirements 8.3 Type I Procedures, Access Valves, and the Open-Book Exam
9 Type II — High-Pressure Appliances
9.1 What Type II Covers: High-Pressure System Overview 9.2 Type II Recovery Methods and Required Evacuation Levels 9.3 Leak Detection, the Repair Triggers, and Recordkeeping 9.4 The R-22 Phaseout, Retrofits, and the Move to Lower-GWP A2Ls
10 Type III — Low-Pressure Appliances
10.1 Low-Pressure System Fundamentals 10.2 Purge Units and Air Management 10.3 Type III Recovery and Procedures 10.4 Type III Leak Testing
11 10. Disposal, Shipping, and Compliance
11.1 Equipment Disposal Requirements 11.2 Refrigerant Shipping and Transport 11.3 Compliance Checklist and Best Practices
12 Final Review and Exam Strategy
12.1 High-Yield Core Section Review 12.2 Type I vs Type II vs Type III: Side-by-Side Review 12.3 How the Exam Works and Exam-Day Strategy
9.4 The R-22 Phaseout, Retrofits, and the Move to Lower-GWP A2Ls
Key Takeaways Explain This Topic AI
R-22 (HCFC-22) U.S. production and import ended January 1, 2020; existing systems are serviced with recovered, recycled, reclaimed, or previously produced R-22
Reclaimed R-22 must be reprocessed to AHRI 700 purity by a certified reclaimer; recovered (same-owner) R-22 may be reused without reprocessing
R-407C is the most common R-22 retrofit but is NOT a true drop-in: it requires changing mineral oil to POE, liquid charging (zeotropic, ~9 degrees F glide), and TXV/filter-drier service
New residential and light commercial AC and heat-pump systems installed since January 1, 2025 must use refrigerant with a GWP below 700 (unless all specified components were made or imported earlier), pushing the industry toward A2L refrigerants R-454B (GWP 466) and R-32 (GWP 675)
Always relabel an appliance after a refrigerant change, and never mix refrigerants or top off a blend that has leaked
Last updated: October 2026
Why R-22 Is Disappearing
R-22 (HCFC-22, chlorodifluoromethane) was the dominant air-conditioning refrigerant for decades, but as an HCFC it contains chlorine and depletes the ozone layer (ODP 0.055), so the Montreal Protocol and the Clean Air Act scheduled it out of production. Type II technicians still service millions of legacy R-22 systems, so understanding the phaseout timeline and the retrofit path is essential exam and field knowledge.
R-22 Phaseout Timeline
- Date Milestone
- January 1, 2004 U.S. HCFC production and consumption cut 35% from baseline
January 1, 2010 No production or import of R-22 except for use in equipment manufactured before January 1, 2010
- January 1, 2020 All new production and import of R-22 ended
- January 1, 2030 Complete HCFC phaseout (all HCFCs) under the Montreal Protocol
- What "No New Production" Means for Service
Since January 1, 2020, the only legal sources of R-22 are:
Reclaimed R-22 — recovered refrigerant that a certified reclaimer has reprocessed to AHRI Standard 700 purity (the same purity as virgin refrigerant). Reclaimed R-22 may be resold and used in any owner's equipment.
Recycled R-22 — refrigerant recovered and cleaned on-site (oil separation, single-pass filtration) for reuse in the same owner's equipment, without reprocessing to AHRI 700.
Existing stockpiles legally produced or imported before the 2020 ban.
With no new supply entering the market, R-22 prices have climbed sharply, which is the practical reason owners increasingly choose to retrofit or replace rather than keep recharging an aging R-22 system.
Retrofit Options
Option What It Involves When It Makes Sense
Retrofit to an HFC blend Change refrigerant (commonly R-407C or R-422D), change oil, adjust components System is otherwise sound and worth keeping
Full system replacement Install new equipment using R-454B or R-32 System is old/inefficient; best long-term value and efficiency
Continue on reclaimed R-22 Keep recharging from reclaimed supply Short remaining service life; cost of reclaimed R-22 still acceptable
R-407C: The Most Common R-22 Retrofit
R-407C (a zeotropic blend of R-32/R-125/R-134a) is the standard retrofit for R-22 because its operating pressures are similar to R-22 — but it is not a true "drop-in." Several changes are mandatory:
Oil change from mineral oil to POE. R-407C is not miscible with mineral oil. The original mineral-oil charge must be removed — often requiring two or three oil changes to get residual mineral oil below ~5%.
Liquid charging only. R-407C is zeotropic with about 9 degrees F of temperature glide ; charging it as vapor would change the blend's composition (fractionation). Charge as liquid, and never top off after a leak — recover and recharge with fresh refrigerant.
Component service. Replace the filter-drier with one rated for HFC/POE, and check/adjust the TXV because R-407C's pressure-temperature behavior differs from R-22.
Relabel the equipment to clearly show the new refrigerant and oil type.
Worked Example: A property manager wants a 60-lb R-22 rooftop unit converted to R-407C. The technician (1) recovers all R-22 to the required evacuation level, (2) drains the mineral oil and refills with POE, runs the system, then drains again to flush residual mineral oil below ~5%, (3) installs a new HFC-rated filter-drier, (4) evacuates the system to a deep vacuum (about 500 microns) to remove moisture — important because POE is hygroscopic, (5) liquid-charges R-407C to the manufacturer's weight, (6) verifies superheat and subcooling, and (7) applies a new label. Skipping the oil change or vapor-charging the blend would cause compressor and performance failures.
The Move to Lower-GWP A2Ls
The R-22 story is now repeating one step further down the GWP ladder. Under the AIM Act's Technology Transitions rule, new residential and light commercial AC and heat-pump systems installed on or after January 1, 2025 must use refrigerant with a GWP below 700 (systems whose specified components were all made or imported before that date may still be installed). That cap removes R-410A (GWP 2,088) — itself the HFC that replaced R-22 — from new systems, in favor of mildly flammable A2L refrigerants:
- Refrigerant Class GWP Replacing
- R-454B A2L 466 R-410A in new AC/heat pumps
- R-32 A2L 675 R-410A in new AC/heat pumps
- R-454C / R-455A A2L ~148 / ~146 R-404A, R-22 in refrigeration
Three practical points for Type II technicians: (1) existing certifications remain valid — no new federal certification is required to service A2Ls; (2) A2L equipment adds safety requirements (charge limits, leak-detection sensors, and spark-source precautions per UL 60335-2-40), and recovery equipment must be rated and listed for A2L service; and (3) existing R-22 and R-410A systems are not outlawed — they may be serviced and recharged for their remaining life, which is why mastery of recovery, leak repair, and retrofit procedures stays essential for years to come.
For the Exam: R-22 production/import ended January 1, 2020 — legacy systems run on recovered, reclaimed, or previously produced R-22. R-407C is not a true drop-in (oil change to POE, liquid charge, TXV/drier service, relabel). New residential and light commercial AC systems have faced a 700 GWP cap since January 1, 2025 , driving the shift to A2L R-454B and R-32.