What replaces R-507A?

R-448A and R-449A are the EPA SNAP-approved replacements for R-507A in commercial refrigeration. Both reduce GWP by approximately 65% and require the same retrofit process as R-404A conversions: oil flush to POE, drier replacement, TXV verification.

HFC Blend

Phasing Down

R-507A

Also known as: R507A, R-507, HFC-507A, AZ-50, Genetron AZ-50

Azeotropic HFC blend for low-temperature commercial refrigeration. GWP of 3,985 is the highest of any common refrigerant — subject to accelerated phasedown pressure.

3,985

GWP

Safety

ODP

Compliance Notice

R-507A has a GWP of 3,985 — exceeding R-404A's 3,922 as the highest-GWP refrigerant in common commercial use. It faces the most severe supply constraints under AIM Act phasedown. Transitioning to R-448A or R-449A is highly recommended for cost management.

EPA / Regulatory Status

R-507A is subject to AIM Act HFC phasedown as one of the highest-GWP refrigerants in commercial use. EPA SNAP has listed lower-GWP alternatives as acceptable. R-507A remains legal for servicing existing equipment.

Cost & Availability Trend

⚡ Volatile

R-507A is facing the sharpest price increases of any common commercial refrigerant due to its extremely high GWP consuming disproportionate AIM Act production allowances. Alternatives R-448A and R-449A typically cost less per pound and deliver substantial long-term cost savings.

Retrofit Notes

Same retrofit process as R-404A to R-448A/R-449A. Pay particular attention to the change in temperature glide — R-507A is a near-azeotrope with minimal glide while R-448A and R-449A have greater glide. Verify evaporator performance during commissioning.

Regulatory Timeline

1994

R-507A introduced as azeotropic low-temperature alternative to CFC-502

2000

R-507A widely adopted for low-temperature commercial refrigeration replacing R-22 and CFC-502

2020

AIM Act phasedown — R-507A highest-GWP refrigerant in common service use

What R-507A Is and Where It Is Used

R-507A is an azeotropic blend of R-125 (50%) and R-143a (50%), developed as a low-temperature replacement for CFC-502 and R-22 in commercial refrigeration. Its azeotropic nature means it behaves like a single-component refrigerant — no fractionation, no temperature glide — which simplifies charging and leak recovery compared to zeotropic blends.

R-507A is used primarily in low-temperature applications: blast freezers, ice cream cases, frozen food display cases, and cold storage warehouses requiring evaporating temperatures below -10°F. Its low boiling point and good low-temperature efficiency made it a preferred specification for applications where R-404A was too warm.

Despite its technical suitability, R-507A's GWP of 3,985 makes it the highest climate-impact refrigerant in common service use. This positions it at the front of AIM Act phasedown attention, and contractors and facility managers should be actively planning transitions for R-507A systems.