HVAC PT Charts

R22 vs R410A: Replacement Decision for Residential AC

Updated October 20, 2026

R-22 is the legacy HCFC (production and import ended 2020); R-410A is the HFC that replaced it from 2010-2024. Different lubricants (MO vs POE), different pressure envelopes (R-410A ~65% higher), different ozone profile (R-22 has ODP, R-410A doesn't). Direct retrofit is not feasible.

R-22 AHRI Guideline N service cylinderIllustration of a refrigerant cylinder painted light green gray (RAL 7044), the color AHRI Guideline N-2017 calls for on all new refrigerant containers from 2020. Label: R22, safety class A1, GWP 1,810. No red band: AHRI Guideline N-2017 reserves it for flammable refrigerants.R22A1GWP 1,810
R-410A AHRI Guideline N service cylinderIllustration of a refrigerant cylinder painted light green gray (RAL 7044), the color AHRI Guideline N-2017 calls for on all new refrigerant containers from 2020. Label: R410A, safety class A1, GWP 2,088. No red band: AHRI Guideline N-2017 reserves it for flammable refrigerants.R410AA1GWP 2,088
R-22 (A1, no flammability band) versus R-410A (A1, no flammability band). Both ship in the AHRI Guideline N light gray-green service cylinder (RAL 7044) industry-uniform since 2020; ASHRAE 34 safety class alone drives the shoulder-band difference.
HCFCA1 Lower toxicity, no flame propagation
GWP (100-yr)
1,810
Lubricant
MO, AB
Glide @ 0°C
0.0°F
HFC blendA1 Lower toxicity, no flame propagation
GWP (100-yr)
2,088
Lubricant
POE
Glide @ 0°C
0.2°F

PT curves, overlaid

Both refrigerants are pure or near-azeotropic — single curve per series.

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.

Saturation pressure (PSIG) at common service temperatures
TemperatureR-22R-410AΔ vs R-22
−20°F10 PSIG26 PSIG+157.9%
0°F24 PSIG48 PSIG+101.5%
40°F69 PSIG119 PSIG+73.3%
70°F121 PSIG202 PSIG+66.1%
95°F182 PSIG296 PSIG+63.0%
120°F260 PSIG419 PSIG+61.3%
Pressure delta: R-410A vs R-22 (% deviation)0%−174%−87%+87%+174%−20°F+157.9%0°F+101.5%40°F+73.3%70°F+66.1%95°F+63.0%120°F+61.3%

Pressure delta visualization: positive = R-410A 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-410A same rule applies.

Property differences side by side

Key differences at a glance
  • GWP impact: R-22 = 1,810, R-410A = 2,088 (+15% vs R-22). GWP delta is modest.
  • Lubricant: R-22: MO/AB; R-410A: POE. Retrofit requires oil change (mineral oil to POE).
  • AIM Act status: R-410A is affected by AIM Act phase-down; the other is not. Drives new-equipment specification decisions in US market.

Properties side by side

PropertyR-22R-410A
TypeHCFCHFC blend
ASHRAE classA1A1
CompositionPure50.0% R-32 / 50.0% R-125
GWP (100-yr)1,8102,088
ODP0.0550
LubricantMO, ABPOE
Boiling point @ 1 atm−40.8°C−51.4°C
Critical point96.2°C / 709 PSIGBlend (locus, not point)
Temp glide0.00°F0.19°F
AIM Act affectedNoYes

Choose R-22 if…

Servicing existing R-22 equipment. Reclaimed R-22 remains legal indefinitely under current EPA rules. New equipment production was banned in 2010; virgin R-22 production and import ended January 1, 2020. Service supply comes from reclaimed material at premium prices.

Choose R-410A if…

Servicing existing R-410A equipment manufactured 2010-2024. R-410A is itself now phased down under the AIM Act for new equipment beginning January 1, 2025, but existing R-410A equipment remains serviceable with reclaimed R-410A. New residential equipment installations now use R-32 or R-454B (A2L).

When neither is ideal

For new residential AC equipment installations from 2025 onward, the choice is R-32 or R-454B (both A2L, GWP 675 and 465 respectively). For R-22 systems needing major work, full system replacement with new R-32 or R-454B equipment is typically more cost-effective than retrofit — and more energy-efficient than R-22-era equipment.

Retrofit and transition

R-22 to R-410A is NOT a simple-swap retrofit. Three blockers, in priority order:

1. Pressure envelope mismatch. R-410A operates at approximately 65% higher pressures than R-22 across the operating envelope. At 95°F outdoor ambient, R-22 saturation is ~181 PSIG vs R-410A ~289 PSIG. R-22-rated components (condenser coil, line set, expansion device, compressor) are not pressure-rated for R-410A operation and would experience accelerated failure.

2. Lubricant incompatibility. R-22 uses mineral oil (MO) or alkylbenzene (AB); R-410A requires polyolester (POE) oil. Mixing mineral oil with R-410A produces chemical decomposition and sludge formation. Even a complete oil flush typically leaves enough residual mineral oil to cause long-term reliability issues.

3. Component sizing. R-410A's higher volumetric capacity means an R-410A system can use a smaller compressor for the same cooling output — but conversely an R-22 compressor running R-410A would be undersized for the system, producing inadequate capacity even before the pressure issues caught up with it.

For systems requiring a refrigerant change from R-22, the practical paths are:

- R-22 retrofit: R-407C, R-422D, R-438A (Chemours Freon MO99), R-427A (Arkema Forane 427A), R-417A. These are mineral-oil-compatible HFC blends that don't require oil change. Capacity is typically 90-95% of original R-22. All face their own AIM Act phase-down restrictions.

- Full system replacement: New R-32 or R-454B equipment. More efficient than R-22-era equipment. Below the relevant 40 CFR 84.54 limit, though R-32 and R-454B are still regulated HFCs under the allowance phase-down; modernizes the safety class (A2L). Typically the most cost-effective long-term path for systems 15+ years old.

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. One or both refrigerants here are AIM Act-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-410A isn't a direct retrofit

R-22 → R-410A is a full equipment-replacement decision, not a service-time swap. The barriers below are structural (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-410A-rated equipment at end-of-life.

Specific barriers for this pair
  • Lubricant families don't overlap. R-22 runs on MO / AB; R-410A 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 +66% at 70°F. Compressor, TXV, condenser, and service-valve ratings are engineered around R-22's envelope (121 PSIG at 70°F); running R-410A (202 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-410A 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.

Lifecycle and regulatory snapshot
  • GWP profile: R-22 = 1,810 GWP; R-410A = 2,088 GWP. Switching from R-22 to R-410A increases direct refrigerant climate impact by 15%.
  • AIM Act exposure: R-410A is AIM Act-affected; R-22 is not — the transition increases regulatory exposure (unusual direction). One or both have a GWP of 700 or more: US EPA restricts new residential and light-commercial AC and heat pumps at that level, 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): R-22 (GWP 1,810) is below every Regulation (EU) No 517/2014 Annex III GWP threshold. R-410A (GWP 2,088) 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: Service supply of AIM Act-affected refrigerants persists during phase-down via reclaimed and allocated production, with prices rising as supply tightens. Plan for refrigerant cost escalation over equipment lifetime.
  • 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-410A

What a service technician needs to know when transitioning from R-22 to R-410A (or comparing them for new equipment specification). Two scenarios show how the difference affects a service call.

1
Service problemR-22 ↔ R-410A

Pressure envelope check for R-22 → R-410A

Scenario · Field tech needs to know: do R-22 service tools handle R-410A, or does the pressure delta require new equipment? PT chart comparison at service temperatures gives the answer.

Comparison
TempR-22R-410AΔ
40°F69 PSIG119 PSIG+73.3%
70°F121 PSIG202 PSIG+66.1%
95°F182 PSIG296 PSIG+63.0%
Action required · Large pressure delta — equipment changes required
Pressure delta exceeds typical retrofit-acceptable margin. Component pressure ratings need engineering review; full equipment replacement is often the right answer rather than retrofit.
Fix
Component pressure ratings must be verified for the higher-pressure refrigerant. R-410A-rated service equipment (800 PSI gauges) handles many newer refrigerants, but R-744 (transcritical) requires 3000+ PSI components.
2
Service problemR-22 ↔ R-410A

Service-side implications: lubricant and safety

Scenario · Beyond pressure envelope, the switch from R-22 to R-410A affects lubricant, safety class, and operating procedure.

Comparison
ConcernR-22R-410AAction
LubricantMO/ABPOEOil change required
Safety classA1A1No change
Glide0.0°F0.2°FMinor
Investigate · Lubricant change required for retrofit
Standard HFC retrofit: drain old oil, flush system, replace with new lubricant family, charge by weight.

When to use which tool for this comparison

Frequently asked

›Why is R-22 so expensive now?

US production and import ended January 1, 2020 under the Montreal Protocol HCFC phase-out. Service supply now comes from reclaimed refrigerant and pre-2020 inventory. The reclaim supply is finite and shrinking as more R-22 equipment retires. Prices have risen sharply.

›Can I just keep my R-22 system running?

Yes, indefinitely under current rules — reclaimed R-22 remains legal to use in existing equipment. However: (1) service costs are high due to refrigerant pricing; (2) major component failures (compressor, condenser) increasingly favor full replacement economics over repair; (3) R-22 equipment is typically 15-25+ years old with diminishing remaining service life; (4) new R-32/R-454B equipment is more efficient, reducing operating costs.

›What pressures do R-22 vs R-410A systems run at?

Very different. At 95°F outdoor ambient on a properly-charged system: R-22 typical operating pressures are ~70 PSIG suction and ~250 PSIG discharge. R-410A is ~135 PSIG suction and ~380 PSIG discharge — about 65% higher across the envelope. Service manifold gauges are rated differently for the two systems (R-22 typically 500 PSI high-side max; R-410A 800 PSI high-side max).

›Is R-410A being phased out too?

Yes — under the AIM Act. R-410A's GWP of 2,088 places it above the 700-GWP threshold for new residential AC equipment beginning January 1, 2025. New equipment uses R-32 (GWP 675) or R-454B (GWP 465). Existing R-410A equipment continues to be serviceable with reclaimed R-410A. The transition timeline is more gradual than R-22's was, but R-410A is on the same trajectory.

›What lubricant does each refrigerant use?

R-22 uses mineral oil (MO) or alkylbenzene (AB). R-410A requires polyolester (POE) oil. The two lubricant classes are chemically incompatible — mixing them produces sludge formation and accelerated component wear. Even after a hypothetical retrofit with oil flushing, residual mineral oil typically remains in the system and causes long-term reliability issues.

›Should I retrofit my R-22 system or replace it?

Depends on age, condition, and economics. Under 10 years with no leaks and intact compressor: continue on reclaimed R-22 (legal, available at premium prices) or consider mineral-oil-compatible HFC retrofit (R-407C, R-422D, R-438A, R-427A). 10-15 years with isolated leak: repair and consider retrofit as a medium-term bridge. Over 15 years, multiple leaks, or compressor concerns: full replacement with new R-32 or R-454B equipment — typically more cost-effective long-term and more efficient.

›Can a homeowner tell which refrigerant their system uses?

Check the data plate on the outdoor unit. It will explicitly state the refrigerant type (R-22, R-410A, R-32, or R-454B). Service cylinders are also color-coded: R-22 light green, R-410A pink, R-32 and R-454B in A2L-marked cylinders. Equipment installed pre-2010 is almost always R-22; equipment installed 2010-2024 is almost always R-410A; equipment installed 2025+ in the US is R-32 or R-454B.

Related

Sources & provenance

  • Saturation pressures from CoolProp 7.2.0 (Bell, Wronski, Quoilin, Lemort 2014, doi:10.1021/ie4033999)
  • Safety classifications per ANSI/ASHRAE Standard 34-2022
  • GWP values on the US EPA basis (40 CFR 84 / IPCC AR4), with IPCC AR4/AR5/AR6 shown where listed
  • Regulatory context: AIM Act (40 CFR Part 84), EU F-Gas Regulation 517/2014 + 2024/573, Kigali Amendment to Montreal Protocol
  • Service-cylinder color convention: AHRI Guideline N-2017 (RAL 7044 industry-uniform since 2020)
  • R-22: CoolProp 7.2.0
  • R-410A: CoolProp 7.2.0 mixture model: R-32/R-125, 50/50% by mass