Will MRCOOL Use R-32 Refrigerant?

MRCOOL Refrigerant Update: Why We’re Transitioning to R-454B – Not R-32

MRCOOL receives frequent questions about refrigerant options, particularly regarding R-32. While R-32 is a valid low-global-warming potential (GWP) refrigerant used by some manufacturers, MRCOOL has chosen to transition from R-410A to R-454B. This decision aligns with federal refrigerant phase-down mandates and internal safety, efficiency, and environmental considerations.

🔍 R-410A vs. R-454B – Key Differences

✅ Why MRCOOL Is Transitioning to R-454B

R-454B offers several technical and environmental advantages over both R-410A and R-32:

• Lower GWP than R-32: R-454B has a GWP of ~466, making it more environmentally responsible than R-32 (~675).

• Milder pressure levels: Closer to R-410A, which simplifies engineering and retrofitting.

• Better compatibility: More direct design and service alignment with existing MRCOOL systems.

• Compliance: Meets the AIM Act requirements and aligns with future EPA regulations.

🚫 Will MRCOOL Units Use R-32?

Although R-32 is an industry-approved refrigerant with low GWP, MRCOOL is not using R-32 in any current or upcoming products. MRCOOL systems are engineered specifically for R-454B and are not compatible with R-32.

⚠️ Important: Safe Refrigerant Handling

Refrigerants are not interchangeable. Attempting to charge or modify a system with the wrong refrigerant can damage the unit, void the warranty, and may create a hazardous condition. Always use the refrigerant type specified on the unit’s nameplate.

🛠️ Safety & Service Considerations for R-454B

R-454B is classified as A2L – mildly flammable, and while safe when properly handled, it requires:

• Use by certified HVAC professionals for refrigerant servicing

• EPA Section 608 certification for anyone handling refrigerant

• Compliance with ASHRAE 15 and UL 60335-2-40

• Proper ventilation during installation and maintenance

• Adherence to updated storage and transport regulations

❗ Important Note for DIY Installations
Certain MRCOOL systems—such as those in the DIY® product line—are pre-charged with refrigerant and designed for installation without requiring refrigerant handling. These systems use sealed Quick Connect® lines that do not require EPA certification for proper installation, unless otherwise prohibited by local codes.

DIY systems are safe for homeowner installation when used as directed and do not require refrigerant recovery, charging, or system evacuation.
However, any attempt to open or modify the refrigerant circuit does classify as refrigerant handling and must only be performed by a licensed technician.

📆 Regulatory Context: Why This Matters

The U.S. Environmental Protection Agency is reducing the production and import of high-GWP HFC refrigerants under the AIM Act, with significant cuts implemented between 2022 and 2036. Manufacturers like MRCOOL are required to adapt their product lines to use next-generation refrigerants that support climate goals and regulatory compliance.

For full refrigerant specifications, installation procedures, and service guidelines, refer to the official MRCOOL documentation or consult a licensed HVAC technician. This article is maintained by MRCOOL employees as a technical reference to support accurate and safe use of our systems.