R-407C
R-407C was built to replace R-22: similar pressures, POE oil, and a straightforward changeout. In commercial refrigeration it appears mostly in medium-temperature equipment, and manufacturer selection tables often rate it alongside R-407A[1].
Its GWP of 1,774 puts it over the 1,400 interim limit from the May 2026 rule, so new installs in the GWP-limited subsectors cannot use it (91 FR 31284)[2]. Existing systems stay legal to run and service.
R-407C quick facts
| Type | HFC blend: 23% R-32, 25% R-125, 52% R-134a |
| ASHRAE safety class | A1 (no flame propagation) |
| GWP (AIM Act exchange values) | 1,774 (computed per 40 CFR 84.64) |
| Temperature glide | About 8 to 10 °F. Bubble for charging, dew for superheat |
| Lubricant | POE |
| Common use | R-22 replacement in AC and medium-temperature refrigeration |
Regulatory status
| Running and servicing existing equipment | Allowed[2] |
| Buying bulk cylinders | Section 608-certified buyers only[3] |
| New remote condensing units | Not allowed since Jul 27, 2026 (over the 1,400 interim limit)[2] |
| New supermarket systems | Not allowed from Jan 1, 2027[2] |
| New cold storage systems | Not allowed since Jul 27, 2026[2] |
Rules
Federal
R-407C's GWP of 1,774 is over the interim limits for every restricted refrigeration subsector, so the interim dates end new R-407C installs there (91 FR 31284)[2]. The rule restricts new systems. It does not ban running or servicing existing equipment[2].
| Subsector | Limit | Date | R-407C outcome |
|---|---|---|---|
| Remote condensing units (retail food) | GWP 1,400 interim | Jul 27, 2026[2] | GWP 150/300 on Jan 1, 2032 |
| Supermarket systems | GWP 1,400 interim | Jan 1, 2027[2] | GWP 150/300 on Jan 1, 2032 |
| Cold storage warehouses | GWP 700 interim | Jul 27, 2026[2] | GWP 150/300 on Jan 1, 2032 |
Five consolidated petitions challenge the May 2026 rule in the D.C. Circuit (lead case HARDI v. EPA, No. 26-1168)[2]. The dates above are current law while the litigation runs.
State
Each row below is checked against the state's own regulation text:
| State | Rule | Effective |
|---|---|---|
| Washington | Retail food refrigeration over 50 lb charge (new): GWP over 150 prohibited, which covers R-407C | Jan 1, 2025 |
Vermont (10 V.S.A. § 586), Maryland, and Rhode Island restrict listed substances in supermarket and condensing-unit subsectors. Their legacy lists target R-404A-class blends rather than R-407C. California's SB 1206 bulk-sale threshold reaches GWP 1,500 in 2030, which does not cover R-407C, and 750 in 2033, which does. Verify with your local authority having jurisdiction before an install decision.
Buying R-407C
Bulk R-407C can only be sold to Section 608-certified technicians and related buyers under 40 CFR 82.154[3].
Replacements
For new equipment in the restricted subsectors, R-448A and R-449A carry the interim window through 2031, and CO2, R-290, R-454C, and R-455A carry the 2032 limits[2]. Existing R-407C systems keep running. The AIM Act phasedown (40 CFR 84.7) will push service prices up over time[7].
R-407C PT chart
Saturation pressures for R-407C from -40 °F upward, computed from reference equations of state[6]. R-407C has one of the larger glides in common use, about 8 to 10 °F, so the bubble and dew columns differ by roughly 13 psi at box temperatures. Charging and subcooling use bubble, and superheat uses dew.
| Temp (°F) | Liquid / bubble (psig) | Vapor / dew (psig) |
|---|---|---|
| -40 | 2.7 | -2.3 |
| -35 | 5.1 | -0.4 |
| -30 | 7.7 | 1.6 |
| -25 | 10.6 | 3.9 |
| -20 | 13.7 | 6.5 |
| -15 | 17.2 | 9.3 |
| -10 | 20.9 | 12.3 |
| -5 | 25.0 | 15.7 |
| 0 | 29.5 | 19.4 |
| 5 | 34.3 | 23.5 |
| 10 | 39.5 | 27.9 |
| 15 | 45.2 | 32.7 |
| 20 | 51.2 | 37.9 |
| 25 | 57.7 | 43.5 |
| 30 | 64.7 | 49.6 |
| 35 | 72.2 | 56.1 |
| 40 | 80.2 | 63.2 |
| 45 | 88.8 | 70.7 |
| 50 | 97.9 | 78.8 |
| 55 | 107.6 | 87.5 |
| 60 | 117.9 | 96.8 |
| 65 | 128.9 | 106.7 |
| 70 | 140.5 | 117.3 |
| 75 | 152.8 | 128.5 |
| 80 | 165.8 | 140.5 |
| 85 | 179.6 | 153.2 |
| 90 | 194.1 | 166.7 |
| 95 | 209.4 | 181.0 |
| 100 | 225.5 | 196.1 |
| 105 | 242.4 | 212.1 |
| 110 | 260.3 | 229.0 |
| 115 | 279.0 | 246.9 |
| 120 | 298.6 | 265.8 |
| 125 | 319.2 | 285.7 |
| 130 | 340.7 | 306.6 |
Use the vapor (dew) column to check superheat at the suction line. Use the liquid (bubble) column to check subcooling at the liquid line and for charging. R-407C glide is about 8 to 10 °F. Using the wrong column misstates superheat by several degrees. R-407C values are computed, not transcribed; see Sources.
Equipment rated for R-407C
Walk-in unit cooler models whose maker publishes R-407C ratings, usually in a shared column with R-407A. Each page shows the full specifications with the page each value comes from.
939 models in the database carry R-407C ratings. A sample:
Questions
- Is R-407C being phased out?
New installs in the GWP-limited refrigeration subsectors ended with the interim limits (July 27, 2026 for remote condensing units, January 1, 2027 for supermarkets, per 91 FR 31284). Existing systems stay legal to run and service, and R-407C remains common in AC applications not covered by those limits.
- Can R-407C replace R-22?
That is what it was designed for. The changeout needs POE oil and attention to the glide when setting superheat. Check the equipment manufacturer's retrofit guidance for TXV and charge adjustments.
- Why do my gauges disagree with the box temperature on R-407C?
Glide. R-407C evaporates across a temperature range of roughly 8 to 10 degrees F, so a single saturation temperature does not exist at a given pressure. Use the dew column for superheat and the bubble column for subcooling.
References
- ^1.40 CFR part 84, Appendix A: GWP exchange values (eCFR)
- ^2.91 FR 31284 (May 26, 2026): Technology Transitions reconsideration final rule
- ^3.40 CFR 82.154: refrigerant sales restriction and venting exemptions (eCFR)
- ^4.88 FR 73098 (Oct 24, 2023): Technology Transitions final rule
- ^5.Chapter 173-443 WAC: Washington HFC regulation
- ^6.CoolProp 8.0 mixture models (Bell et al. 2014, doi:10.1021/ie4033999)
- ^7.40 CFR 84.7: HFC phasedown schedule (eCFR)
Updated