R-452A PT Chart and Refrigerant Profile

Where you will find R-452A

R-452A (Chemours Opteon XP44, Arkema Forane 452A) is mostly a transport refrigerant: truck and trailer units and refrigerated containers, plus retail remote condensing units and other DX commercial refrigeration (Arkema). It was introduced as a lower-GWP alternative to R-404A and R-507A, both for new units and for retrofits.

Check the unit’s data plate and any retrofit tag. Transport units are often converted in the field, so the compressor label may still read R-404A. At a 40°F evaporating dew point, this site’s computed chart gives R-452A 78.5 psig against 85.4 psig for R-404A; on the liquid side at 100°F, 246.9 psig bubble against 236.8 psig. A transport tech who sees those offsets on an “R-404A” unit should look for a retrofit tag before adding refrigerant.

Charging R-452A

R-452A is a zeotropic blend with about 7.5°F of glide at 40°F evaporating and 6.6°F at 100°F condensing (computed). Chemours says to remove liquid only from the charging cylinder. Vapor drawn off a zeotropic cylinder has a different composition from the liquid, which shifts the blend in both the cylinder and the system.

At 40°F the bubble pressure is 91.4 psig and the dew pressure 78.5 psig. Use the dew column with suction pressure for superheat and the bubble column with liquid-line pressure for subcooling; the glide calculator shows the spread at your reading, and the PT chart guide explains the two columns.

For a retrofit from R-404A or R-507A, Chemours suggests starting at about 85% of the original charge by weight (XP44 retrofit guidelines). Transport units are charged to the unit manufacturer’s procedure; on TXV and EEV commercial systems, finish to the manufacturer’s subcooling target with the subcooling calculator. The CEC-based target superheat method is for comfort air conditioners, not refrigeration.

After a leak repair, Arkema states that R-452A can be topped off rather than requiring a full recovery and recharge. Repair the leak first, and charge the top-off as liquid.

This chart was spot-checked against Chemours’ XP44 pressure-temperature data: within 0.7 psi at 40°F and below, and within 1.7 psi (0.7%) at 100°F, as listed in the validation section below.

Oil and compatibility

R-452A uses POE. Chemours states that the existing POE is suitable when converting R-404A or R-507A systems, and Copeland’s approved-lubricant bulletin (AE 93-11) lists POE-32 for its pre-approved R-452A applications. Check the compressor or transport-unit manufacturer’s approval before converting.

Whether R-452A tolerates residual mineral oil or alkylbenzene was not confirmed in the sources reviewed for this page, so treat R-22 conversions as a question for the refrigerant and compressor makers. See the oil types guide.

Safety, handling and recovery

R-452A is safety class A1: lower toxicity, no flame propagation. Standard tools and a recovery machine certified to Appendix B3 (AHRI 740) apply.

Under Section 608 it is a high-pressure appliance refrigerant (40 CFR 82.152), so Type II or Universal certification is required, and sales are restricted to certified technicians. Recover to 0 in Hg on systems under 200 lb and to 10 in Hg on 200 lb or more (equipment made after November 15, 1993, 40 CFR 82.156).

The HFC Emissions Reduction and Reclamation rule (89 FR 82682) applies leak repair requirements from January 1, 2026 to appliances with 15 lb or more of HFC. EPA has proposed exempting transport refrigeration units from those leak repair rules (91 FR 30532, May 26 2026), but as of this page’s review date that proposal was not final.

No legacy color for R-452A was verified. New containers since January 1, 2020 are light green-gray (RAL 7044) under AHRI Guideline N-2017, with the refrigerant identified on the label. See cylinder colors.

Status and replacements

Servicing existing R-452A units is legal. Its HFC content is subject to the AIM Act allowance phasedown in 40 CFR 84.7: 60% of baseline in 2024–2028 and 30% in 2029–2033.

For new equipment, R-452A’s GWP of 2,140 is above the limits set by the May 2026 final rule (91 FR 31284): 1,400 for new remote condensing units from July 27, 2026 and new supermarket systems from January 1, 2027, and 700 for new cold storage from July 27, 2026, with lower 150/300 limits from January 1, 2032. It is also above the 700 limit for new intermodal containers with a box temperature of -35°C or higher from July 27, 2026. R-452A is not one of the refrigerants named as restricted for new road and marine transport units in 40 CFR 84.54; check the current rule text for the unit type you are specifying.

From January 1, 2029, servicing refrigerated transport, supermarket systems and automatic commercial ice makers must use reclaimed refrigerant (40 CFR 84.112(e)), which covers most R-452A work.

Among lower-GWP blends, R-454C lists transport refrigeration among its uses; it is A2L, so it needs A2L-rated tools and equipment designed for it. See the R-404A replacement comparison for how R-452A sits against R-448A and R-449A.

Common questions

What oil does R-452A use?

POE. Existing POE can stay when converting from R-404A or R-507A (Chemours); Copeland lists POE-32 for its approved R-452A applications.

Is R-452A a drop-in for R-404A?

It is a retrofit, not a top-off of the old gas. Recover the R-404A, keep the POE, charge R-452A as liquid starting at about 85% of the original charge, and follow the Chemours retrofit guideline and the unit maker’s approval.