R22 vs R454B: Legacy HCFC to Modern A2L Upgrade
Updated October 20, 2026
R-22 is the legacy HCFC residential AC refrigerant (production banned 2020); R-454B is the modern A2L HFC/HFO blend replacement (R-32/R-1234yf 68.9/31.1, GWP 465). Different lubricants, different safety classes, R-454B operates at ~60% higher pressures. Full equipment replacement only — no retrofit path.
- GWP (100-yr)
- 465
- Lubricant
- POE
- Glide @ 0°C
- 2.3°F
PT curves, overlaid
Solid line = bubble, dashed = dew where the refrigerant has significant temperature glide.
Pressure comparison at service temperatures
Side-by-side pressure values at common service temperatures, computed from CoolProp 7.2.0. Useful for retrofit feasibility — pressure deltas within ±20% typically allow retrofit-compatible service equipment; larger deltas require component pressure-rating review.
| Temperature | R-22 | R-454B | Δ vs R-22 |
|---|---|---|---|
| −20°F | 10 PSIG | 24 PSIG | +138.1% |
| 0°F | 24 PSIG | 45 PSIG | +88.4% |
| 40°F | 69 PSIG | 112 PSIG | +63.3% |
| 70°F | 121 PSIG | 191 PSIG | +56.9% |
| 95°F | 182 PSIG | 280 PSIG | +54.0% |
| 120°F | 260 PSIG | 396 PSIG | +52.2% |
Pressure delta visualization: positive = R-454B runs higher than R-22; negative = lower. Service equipment pressure rating matters when delta exceeds ±20% on the discharge side. For R-22 (zeotropic blend) bubble pressure is shown; for R-454B same rule applies.
Property differences side by side
- Safety class change: R-22 (A1) → R-454B (A2L). A2L equipment requirements apply: A2L-listed equipment, charge limits set by the refrigerant's LFL and room, and refrigerant detection where the standard requires it (IEC 60335-2-40).
- GWP impact: R-22 = 1,810, R-454B = 465 (−74% vs R-22).
- Lubricant: R-22: MO/AB; R-454B: POE. Retrofit requires oil change (mineral oil to POE).
Properties side by side
| Property | R-22 | R-454B |
|---|---|---|
| Type | HCFC | HFC/HFO blend |
| ASHRAE class | A1 | A2L |
| Composition | Pure | 68.9% R-32 / 31.1% R-1234yf |
| GWP (100-yr) | 1,810 | 465 |
| ODP | 0.055 | 0 |
| Lubricant | MO, AB | POE |
| Boiling point @ 1 atm | −40.8°C | −50.5°C |
| Critical point | 96.2°C / 709 PSIG | Blend (locus, not point) |
| Temp glide | 0.00°F | 2.32°F |
| AIM Act affected | No | No |
Choose R-22 if…
Servicing existing R-22 equipment with original R-22. Reclaimed R-22 remains legal indefinitely under EPA rules. The equipment chassis and lubricant match original specification. Rising refrigerant cost is the trade-off — service supply comes from reclaimed refrigerant and pre-2020 inventory, and is shrinking.
Choose R-454B if…
New residential AC equipment installations 2025+. R-454B is one of the two dominant A2L replacements for R-410A (R-32 is the other). R-454B is marketed by Carrier as Puron Advance and is a leading choice for new US residential AC lines. GWP 465 (below the 40 CFR 84.54(a)(1)/(c)(1) 700-GWP limit for new residential and light-commercial AC and heat pumps) with the lowest among A2L blends in mainstream residential use.
When neither is ideal
For existing R-22 equipment needing significant work but not yet ready for full replacement: R-22 retrofit blends (R-407C, R-422D, R-438A) preserve the existing chassis with a refrigerant + oil change. These are HFC blends facing their own AIM Act phase-down — a bridge, not a long-term answer. Full replacement with new R-454B or R-32 equipment is the durable path.
Retrofit and transition
R-22 to R-454B is NOT a retrofit — it requires full equipment replacement. Four structural blockers identical to the R-22 → R-32 path:
1. Safety class change (A1 → A2L). R-22 equipment is A1-rated. R-454B is A2L (lower flammability). The transition requires A2L-listed equipment, A2L-rated refrigerant detection where the standard requires it, charge limits per IEC 60335-2-40, ignition-source isolation. Retrofit of A1-rated chassis to A2L is not permitted under most codes.
2. Pressure envelope mismatch. R-454B operates at approximately 50-57% higher pressures than R-22 across the operating envelope. R-22-rated components are not pressure-rated for R-454B operation.
3. Lubricant incompatibility. R-22 uses mineral oil (MO); R-454B requires polyolester (POE) oil. The two are chemically incompatible.
4. Compressor sizing. R-454B's higher volumetric capacity means an R-454B-optimized system uses smaller compressor displacement than R-22 equipment for the same capacity.
For existing R-22 equipment, the practical paths:
- Continue on reclaimed R-22 — legal, increasingly expensive, sustainable for systems with no major issues - R-22 retrofit blend — R-407C, R-422D, R-438A, R-427A; preserves equipment chassis, still faces HFC phase-down - Full system replacement — new R-454B equipment (or R-32, depending on OEM preference); below the relevant 40 CFR 84.54 limit, though both remain regulated HFCs under the allowance phase-down
R-454B vs R-32 for new equipment: This is the OEM-preference choice. Both are A2L. R-454B has slightly lower GWP (465 vs R-32's 675). Performance is comparable; OEM preference, equipment availability, and installer training in your market typically determine the choice.
Regulatory and transition context
Both refrigerants sit in an active regulatory transition driven by climate-impact rules. The transitions affect availability, pricing, and new-equipment specification.
- AIM Act (40 CFR Part 84): US HFC production / import phase-down. Cap declines from 90% allocation (2022) to 15% by 2036. Neither refrigerant is directly affected. US EPA restricts new residential and light-commercial air conditioners and heat pumps using a refrigerant of GWP 700 or more, effective January 1, 2025 (40 CFR 84.54(a)(1)). Limits for other equipment types differ.
- EU: Regulation (EU) No 517/2014, replaced by (EU) 2024/573 (applying from March 11, 2024); 2024/573 uses AR4 GWPs for HFCs and AR6 for other fluorinated gases (recital 8).
- Kigali Amendment to Montreal Protocol (2016): international HFC phase-down framework. The Montreal Protocol has 198 parties; 174 have ratified the Kigali Amendment (as of August 10, 2026). The AIM Act and EU F-Gas are regional implementations. Schedules differ by country group.
- ASHRAE 34-2022: safety classification (A1, A2L, A3, B1, B2L). For A2L refrigerants like R-32, R-454B, R-454C, R-455A: equipment must be A2L-certified, charge limits per IEC 60335-2-40 apply.
Why R-22 → R-454B isn't a direct retrofit
R-22 → R-454B is a full equipment-replacement decision, not a service-time swap. The barriers below are structural (equipment certification, oil chemistry, and pressure ratings), so no field checklist can bridge them. The realistic path is to continue servicing existing R-22 equipment through its useful life, then install new R-454B-rated equipment at end-of-life.
- ASHRAE safety class change (A1 → A2L). R-454B requires equipment certified to UL/IEC 60335-2-40 for A2L: listed or ignition-protected equipment, room-volume charge limits, and (on larger systems) integrated leak detection. Field retrofit of A1-only equipment is not permitted; new equipment must ship with the A2L certification from the factory.
- Lubricant families don't overlap. R-22 runs on MO / AB; R-454B requires POE. Mixing families (mineral oil with POE, for example) produces oil-return failure in the evaporator within hours of operation, so a service-time swap requires a full oil change, system flush, and driver replacement — service labor that typically approaches new-equipment cost on residential-scale systems.
- Saturation pressure delta +57% at 70°F. Compressor, TXV, condenser, and service-valve ratings are engineered around R-22's envelope (121 PSIG at 70°F); running R-454B (191 PSIG) at this delta exceeds the design margins on multiple components. Retrofitting means re-rating hardware, not just changing charge.
Lifecycle and operational context
Beyond the per-service-call decision, the R-22 ↔ R-454B choice also involves regulatory and lifecycle factors. The transition direction (which is the predecessor, which is the successor) is driven by climate policy and the AIM Act phase-down, not technical preference alone.
- GWP profile: R-22 = 1,810 GWP; R-454B = 465 GWP. Switching from R-22 to R-454B reduces direct refrigerant climate impact by 74%.
- AIM Act exposure: Neither refrigerant is directly affected by the AIM Act phase-down. Other regional regulations (EU F-Gas, Kigali signatory implementations) may still apply.
- EU (Regulation (EU) No 517/2014, replaced by (EU) 2024/573): R-22 (GWP 1,810) is below every Regulation (EU) No 517/2014 Annex III GWP threshold. R-454B (GWP 465) meets 2 Annex III placing-on-the-market prohibitions; the earliest is Refrigerators and freezers for commercial use (hermetically sealed equipment) (GWP ≥ 150) from January 1, 2022.
- Service supply outlook: Neither refrigerant faces near-term supply constraints from AIM Act phase-down. Pricing follows normal commodity dynamics.
- TEWI / LCCP framing: Total Equivalent Warming Impact accounts for both direct refrigerant emissions (leakage, end-of-life) and indirect emissions from equipment energy consumption. For HVAC equipment with ≤5% annual leak rate, indirect emissions typically dominate TEWI by 80-90% — meaning equipment efficiency matters more than refrigerant GWP for total climate impact. For commercial refrigeration with higher leak rates, the balance can tip toward favoring low-GWP refrigerants.
Regulatory sources: AIM Act (40 CFR Part 84), EU F-Gas Regulation 517/2014 and update 2024/573, Kigali Amendment to the Montreal Protocol (2016). GWP values on the US EPA basis (40 CFR 84 / IPCC AR4).
Service implications — R-22 → R-454B
What a service technician needs to know when transitioning from R-22 to R-454B (or comparing them for new equipment specification). Two scenarios show how the difference affects a service call.
Pressure envelope check for R-22 → R-454B
Scenario · Field tech needs to know: do R-22 service tools handle R-454B, or does the pressure delta require new equipment? PT chart comparison at service temperatures gives the answer.
| Temp | R-22 | R-454B | Δ |
|---|---|---|---|
| 40°F | 69 PSIG | 112 PSIG | +63.3% |
| 70°F | 121 PSIG | 191 PSIG | +56.9% |
| 95°F | 182 PSIG | 280 PSIG | +54.0% |
Service-side implications: lubricant and safety
Scenario · Beyond pressure envelope, the switch from R-22 to R-454B affects lubricant, safety class, and operating procedure.
| Concern | R-22 | R-454B | Action |
|---|---|---|---|
| Lubricant | MO/AB | POE | Oil change required |
| Safety class | A1 | A2L | A2L equipment |
| Glide | 0.0°F | 2.3°F | Minor |
When to use which tool for this comparison
- R-22 full reference — properties, PT chart, lubricant, retrofit options for R-22.
- R-454B full reference — properties, PT chart, lubricant, retrofit options for R-454B.
- PT Comparison Tool — overlay any 2-4 refrigerants' PT curves interactively.
- Retrofit Compatibility Calculator — five-criterion compatibility analysis with verdict.
- Refrigerant Comparison Guide — long-form sourced reference for all common HVAC refrigerant comparisons.
Frequently asked
›Is R-454B a direct replacement for R-22?
No. R-454B is the modern refrigerant for new R-454B-designed equipment — not a retrofit refrigerant for R-22 equipment. The safety class change (A1 to A2L), pressure envelope difference (~60% higher), lubricant change (mineral oil to POE), and capacity differences all require fundamentally different equipment design. The two refrigerants serve the same residential AC application in completely separate equipment generations.
›What's the difference between R-454B and R-32?
Both are A2L refrigerants for residential AC. R-454B is a 68.9/31.1 R-32/R-1234yf blend with GWP 465 and very small glide (~2°F). R-32 is pure (no glide) with GWP 675. Performance is comparable. The R-454B blend's lower GWP comes from the R-1234yf component; the slight glide is the trade-off.
›What's R-454B's GWP compared to R-22?
R-454B GWP 465 vs R-22 GWP 1,810. R-454B is about 74% lower GWP than R-22, and the lowest GWP among the mainstream A2L residential AC choices. R-22 is being phased out for ozone-depletion concerns (ODP 0.055) under the Montreal Protocol; R-454B has zero ODP and clears the 40 CFR 84.54(a)(1)/(c)(1) 700-GWP limit for new residential and light-commercial AC and heat pumps by a wider margin than R-32 does.
›Is R-454B safe to handle?
It's ASHRAE class A2L — lower flammability with low burning velocity. A2L equipment design (A2L-listed equipment, refrigerant detection where the standard requires it, charge limits, ignition-source isolation) mitigates the flammability risk to acceptable levels. The R-1234yf component is itself A2L. R-454B has been deployed extensively in US residential AC since 2024 with strong safety record. For homeowners: A2L equipment is safe in normal operation; the classification matters for technician procedures, not for everyday use.
›Does R-454B have temperature glide?
Yes — about 2°F at typical operating pressures. This is very small (compare R-407C's 11°F or R-454C's 14°F). The small glide is a feature of the carefully-engineered 68.9/31.1 composition — the blend is intentionally near-azeotropic, simplifying service measurement and avoiding the bubble/dew curve complexity that high-glide blends require. For practical purposes R-454B can often be treated like a near-azeotrope for service measurements.
›What lubricant does R-454B use?
Polyolester (POE) oil — same as R-410A and R-32. Mineral oil (R-22's lubricant) and alkylbenzene are not compatible. POE is hygroscopic, so vacuum and filter-drier handling are important during service.
›Should I install R-454B or R-32 equipment?
Equipment availability in your market is the primary driver. Different OEMs have standardized on one or the other, so the brands your local dealers carry often decide it. Performance is comparable between the two (R-454B slightly lower GWP, R-32 higher discharge temperature). For homeowners, the choice between A2L refrigerants is rarely the binding constraint; pick the equipment brand that fits your application and trust the OEM's refrigerant selection.
Related
R-22 PT chart
Full reference: PT chart, properties, retrofit guidance.
R-454B PT chart
Full reference: PT chart, properties, retrofit guidance.
R-22 operating pressures
Suction/discharge ranges by ambient + diagnostic procedure.
R-454B operating pressures
Suction/discharge ranges by ambient + diagnostic procedure.