By Yevhen Kovalchuk · Updated September 19, 2026 · 6 min read
Short answer
R-404A has a GWP near 3,900, so new supermarket and commercial refrigeration is moving to R-448A and R-449A (GWP about 1,300 to 1,400), R-452A, or to CO2 and propane. The blends are A1 refrigerants that can often retrofit existing POE-oil systems, with changes to the filter drier, expansion valve settings and charge. Which one is allowed depends on the sector's GWP limit and your equipment's manufacturer.
R-404A has a global warming potential of about 3,900, which makes it a main target of the HFC phasedown. The common replacements are R-448A and R-449A, with a GWP of roughly 1,300 to 1,400, and R-452A at about 2,100. In new systems, CO2 (R-744) and propane (R-290) are also used. Existing R-404A systems can still run and be serviced; the replacement question is about new equipment and about whether to convert an old system.
Why is R-404A being replaced?
The AIM Act is cutting production and import of HFCs, and R-404A has one of the highest GWPs among them, so it is the first to get scarce and costly. The Technology Transitions rule also limits refrigerants in new supermarket and cold storage systems. See what the AIM Act is and the January 2027 deadlines.
How do the main replacements compare?
| Refrigerant | Approximate GWP (AR4) | Safety class | Notes |
|---|---|---|---|
| R-404A (for reference) | about 3,900 | A1 | The refrigerant being replaced |
| R-448A | about 1,300–1,400 | A1 | Close match for medium and low temperature; temperature glide |
| R-449A | about 1,300–1,400 | A1 | Similar to R-448A; common in retrofits |
| R-452A | about 2,100 | A1 | Used in transport and some retrofits; higher GWP |
| R-407A / R-407F | about 1,700–1,900 | A1 | Good for medium temperature; weaker at low temperature |
| CO2 (R-744) | 1 | A1 | High pressure, transcritical systems in new supermarkets |
| Propane (R-290) | about 3 | A3 | Self-contained cabinets with small charges; flammable |
GWP varies with the assessment report, so check the basis used in the regulation. Suppliers such as Arkema and Linde publish datasheets for each product.
Which one fits the regulatory limit?
For new supermarket systems, summaries of EPA’s May 2026 rule report an interim limit of 1,400 GWP from January 1, 2027, which R-448A and R-449A are at or near; check the GWP basis EPA uses. For cold storage, the reported interim limit is 700, which these blends do not meet. CO2, ammonia and some HFO-based options are used there. See the Technology Transitions rule update and verify the limit for your sector on EPA’s page.
Can you retrofit an R-404A system?
Often, yes. Manufacturers say R-448A, R-449A and R-452A can work with the existing POE oil, and the system’s performance is close to R-404A. Danfoss advises that only A1 refrigerants should replace R-404A in an existing system. Retrofit practice commonly includes:
- Ask the component makers. Compressor, valve and gasket makers state which refrigerants they approve.
- Recover the R-404A and document the amount.
- Replace the filter drier and check seals, as Arkema and Linde recommend.
- Check the expansion valve and adjust or replace for the new refrigerant’s pressures.
- Charge by liquid because the blends have glide, and follow the manufacturer’s charge guidance, which may differ from the R-404A charge.
- Reset controls and alarms; discharge temperatures and pressures differ slightly.
- Check oil and acid after a short run time; see what oil analysis tells you.
- Relabel the equipment and update leak records.
Do not mix refrigerants or top off an R-404A system with a different one. A different charge can also change how the compressor behaves; see how to read a compressor nameplate to confirm the approved refrigerant.
What about CO2 and propane?
- CO2 transcritical systems are common in new supermarkets. They run at very high pressures and need specialized components and trained technicians. They are not a retrofit for an R-404A rack.
- R-290 is used in self-contained cabinets and small units with limited charge sizes because it is flammable. Charge limits are set by product safety standards and codes.
What does a good decision process look like?
- New build: consider CO2 or lower-GWP options that fit the 2032 limits that return in the rule. An HFC blend at 1,400 GWP may be allowed now but could face tighter expectations later.
- Existing system, near end of life: compare cost of retrofit, the refrigerant price trend and the cost of replacement.
- Existing system, healthy: keep running and keep leak records; plan the replacement.
- Cold storage or freezer plant: look at ammonia or CO2 designs; see industrial chillers for process cooling basics.
What should you check before choosing a replacement?
A refrigerant swap touches more than the refrigerant, so a short pre-check saves surprises.
- Compressor and oil compatibility. Some blends behave differently with the existing oil; compressor oil types explains why oil choice matters in a retrofit.
- Component ratings. Confirm that valves, controls and relief devices suit the new refrigerant’s pressures and glide.
- Leak history. Retrofitting a system that leaks only moves the problem; see EPA 608 leak repair rules for the repair expectations that apply to larger systems.
- Whole-plant context. Supermarkets face their own timelines; supermarket refrigeration GWP limits and options is worth reading alongside this article.
- Recovery and handling. Recovered refrigerant has its own rules; see refrigerant reclaim and recycling.
Document the starting condition, the choice and the reasons. If an equipment manufacturer publishes a retrofit guideline for your model, follow it, and confirm current EPA requirements at epa.gov before making a decision.
Frequently asked questions
Is R-448A a drop-in replacement for R-404A?
Not exactly. It is a close match and is often used in retrofits, but it needs a new filter drier, valve checks and the manufacturer’s approval.
Is R-404A banned?
No. Existing systems can run and be serviced. New equipment and refrigerant supply are restricted.
Which is better, R-448A or R-449A?
They are close in performance and GWP. Choice depends on the compressor manufacturer’s approval, availability and local supplier support.
SpecServis follows these changes as we plan to enter the Central Texas market. We are looking for technicians and partners. See our open positions or partnership options.
