Among many evolving global environmental regulations, there is a consistent call for organizations and facilities to shift to refrigerants with a GWP below 750.
This change affects facility equipment choices, maintenance protocols, and long-term environmental compliance and missions reduction planning.
At Vertiv, we support operators, consultants, and practitioners by providing the technical expertise and hardware solutions to help you navigate these increasingly complex requirements. Whether you manage a single data center or oversee a global portfolio, use these resources to:
- Identify the refrigerants fit for your infrastructure’s needs and specific cooling architecture.
- Maintain compliance with shifting local, regional, and international standards.
- Select the solution that balances energy efficiency with new safety classifications.

Optimized power usage
Switching to low-GWP refrigerants features a redesigned thermal chain engineered for peak efficiency. By reducing cooling-related power draw, these units directly support lower power usage effectiveness (PUE) and reduced site carbon emissions.1
Enhanced operational resilience
Next-generation low-GWP systems integrate advanced sensing and control technologies as a standard. This modernization provides detailed insight into system health and refrigerant circuits, allowing for more proactive management of your cooling infrastructure.
Lower direct emission profile
Switching to low-GWP refrigerants offer a 68% or greater2 reduction in global warming potential compared to legacy high-GWP R-410A. This significantly lowers the potential climate impact of cooling inventory and supports Scope 1 carbonization targets.
Designed for long-term investment security
Transitioning to low-GWP refrigerants keeps your facility in sync with the latest industry standards for parts and service. By using the new market-standard fluids, you avoid the complications of maintaining legacy equipment and benefit from a resilient, modern supply chain for the life of your asset.
1 Study done on Vertiv™ CoolPhase and Vertiv™ CooLoop units shows greater efficiency than previous high-GWP solutions on the market
Are low-GWP refrigerants flammable?
Some low-GWP refrigerants, like R454B and R32, are classified as A2L refrigerants, meaning they have “low flammability”. Breaking the classification down:
- The first letter indicates the level of toxicity for a given refrigerant. For an A2L refrigerant, A indicates the refrigerant with lower toxicity.
- The number indicates how flammable the refrigerant is, with 1 being non-flammable and 3 being highly flammable. 2 specifies that the refrigerant is flammable.
- Finally, the second letter, when present, indicates the level of flammability within the numeric class. L signifies that, while the refrigerant is flammable, it has a low burning velocity.

The reality of “lower flammability”
It is helpful to think of A2L refrigerants not as "explosive," but as “stubborn." Unlike the highly flammable gases used in blowtorches or grills, A2Ls are difficult to ignite and even harder to keep burning.
| Property | A2L (e.g., R-454C) | A3 (e.g., Propane R-290) | Impact on your facility |
|---|---|---|---|
| Lower flammability limit (LFL) | High: 292g/m3 | Low: 38g/m3 | A2Ls require approximately 8x the concentration of propane to become flammable. |
| Minimum ignition energy | High: 300–1000+ mJ | Extremely low: 0.25 mJ | A2Ls are resistant to common static and low-energy electrical sparks. |
| Burning velocity | Slow: 1.6 cm/s | Fast: 46 cm/s | If ignited, A2L flames spread slower than a person walks. A3 flames spread rapidly. |
Source: U.S. Environmental Protection Agency - GreenChill Advanced Refrigeration Partnership presentation,2022.
Even though the “flammable” label is a shift, we've designed our equipment to help manage these risks. Our updated product design focuses on minimizing and mitigating ignition risks, and our patent-pending A2L leak mitigation controls package is built to send alerts well before refrigerant concentration levels become a concern. When you combine these features with proper ventilation and safety protocols, using A2L refrigerants becomes a predictable part of your daily operations rather than a safety or compliance hurdle.
Global mandates driving the shift
Refrigerant options
Evaluating available compounds - Vertiv and its partners are continuously developing systems optimized for low-GWP refrigerants. Commonly used refrigerants are listed in the table below. The selection depends on regional regulations, system compatibility, flammability classification, and operating density. For example, A2L refrigerants like R-454B are widely accepted in North America, while A1 refrigerants such as R-513A are preferred in the EU due to stricter flammability constraints.
*GWP Values based on AR4 by IPCC
| Refrigerants | Chemical compound | Classification | GWP value* |
|---|---|---|---|
| R410A | HFC Blend | A1 | 2088 |
| R407C | HFC Blend | A1 | 1774 |
| R134a | HFC | A1 | 1430 |
| R32 | HFC | A2L | 675 |
| R513A | HFC/HFO Blend | A1 | 631 |
| R454B | HFC/HFO Blend | A2L | 466 |
| R515A | HFC/HFO Blend | B1 | 7 |
| R1234ze | HFO | A2L | 7 |
| R1234yf | HFO | A2L | 4 |
| R290 | HC | A3 | 4 |
| R744 (Carbon Dioxide) | Natural Refrigerant | A1 | 1 |
Source: Vertiv
Choose your right-sized solutions
Enable exceptional scale, velocity, and quality for every project regardless of size and complexity.
| Product name | Vertiv™ CoolPhase Perimeter | Vertiv™ CoolPhase Row | Vertiv™ CoolPhase Wall | Vertiv™ CoolPhase Ceiling | ||
|---|---|---|---|---|---|---|
| Solution type | CRAC + free cooling economization |
CRAC | Compact CRAC |
In-row | Wall-mounted split | Ceiling-mounted |
| Capacity range | 50-265 kW | 35-105 kW | 11-29 kW | 30-40 kW | 3.5-11 kW | 3.5-28 kW |
| Refrigerant | R-454B | R-454B | R-454B | R-32 | R-32 | R-32 |
| Product name | Vertiv™ CoolPhase Condenser | Vertiv™ EconoPhase | Vertiv™ CoolPhase Condensing Unit |
Vertiv™ Liebert® AFC | Vertiv™ CoolLoop Trim Cooler |
|
|---|---|---|---|---|---|---|
| Solution type | Microchannel condenser | V-shaped microchannel condenser | Pumped refrigerant economization unit | Microchannel condensing unit | Free cooling chiller | Free cooling chiller |
| Capacity range | 28-220 kW | 330-440 kW | 50-250 kW | 3.5-40 kW | 900-1800 kW | 850-3000 kW |
| Refrigerant | R-454B | R-454B | R-454B | R-32 | R1234ze | R1234ze |
Resources
Contact a Vertiv representative
Need help choosing the right refrigerant or cooling solution for your system? Our team can guide you toward the safest, most efficient option available.











