WIRED FOR SAFETY: WHAT YOU NEED TO KNOW ABOUT A2L REFRIGERANTS AND ELECTRICAL COMPONENTS IN FOODSERVICE DESIGN

As the HVACR world shifts toward greener, low-GWP refrigerants, A2Ls have stepped into the spotlight—but not without a few sparks. While they promise eco-friendly performance, these mildly flammable refrigerants come with a unique set of safety challenges, especially when it comes to electrical components. Whether you’re designing, specifying, or installing A2L systems, understanding how to safely pair these refrigerants with the right electrical setups is crucial. Here’s what you need to know to stay compliant—and stay safe.

 

However, the “lower flammability” classification of A2L refrigerants introduces unique considerations, particularly concerning electrical components. Specifying engineers and contractors must be well-versed in safety requirements and risk mitigation strategies related to applications, equipment, and component designs. ​

Understanding Protected vs. Unprotected Systems

A2L system safety compliance varies based on the system’s design:​

1. Protected Systems: These systems ensure that no part of the cooling mechanism is within the food storage compartment. Safety measures are implemented to prevent refrigerant leaks from posing fire or explosion hazards, typically by enclosing the refrigerant system to prevent leaked gas from reaching the storage area. ​

2. Unprotected Systems: In these systems, components of the cooling mechanism are located inside the food storage compartment. A refrigerant leak could create explosive conditions near electrical components, necessitating additional safety measures. This might involve special certifications for individual components or an overarching system-level certification. ​

Achieving Compliance: Component-Level vs. System-Level Certification

For unprotected systems, compliance with A2L safety standards can be achieved through:​

1. Component-Level Certification: Individual electrical components are certified to meet safety standards. For instance, Copeland is qualifying its electrical components for individual certification. ​

2. System-Level Certification: The entire system, including its electrical enclosure, undergoes certification to ensure it meets safety standards. ​

Only one certification approach is necessary to achieve compliance.​

Key Electrical Components and Safety Measures

When integrating A2L refrigerants, attention must be given to specific electrical components, including:

1. Relays/contactors and devices used for switching electrical currents on/off​

2. Controllers​

3. Variable-frequency drives (VFDs)​

4. Electrical enclosures housing the system​

These components must adhere to stringent enclosure tolerances to prevent flame propagation. For example, the maximum size of openings in a device’s enclosure must be limited to prevent internal sparks or flames from escaping. This ensures that even if a device sparks internally, the flame will not propagate outside the component. ​

Certification Exceptions

Certain relays and switching devices may be deemed inherently compliant and exempt from testing if they meet specific criteria:

1. Capable of 100,000 cycles, as specified in Clause 24.​

2. The switched electrical load (Lₑ) in kVA is less than or equal to:​

   • Lₑ = 5 × (6.7/Sᵤ)⁴ when breaking all phases (~66 kVA)​

   • Lₑ = 2.5 × (6.7/Sᵤ)⁴ when breaking two legs of a three-phase load, or when breaking one or two legs of a single-phase load​

Where Sᵤ represents the burning velocity in cm/s.

Flame-Arrest Enclosures

For system-level certification, enclosures must withstand internal ignition of leaked A2L refrigerant vapor without transmitting flame externally. A qualifying enclosure ensures that even if internal ignition occurs, flames will not escape or ignite the external environment. ​

Conclusion

The adoption of A2L refrigerants necessitates meticulous attention to electrical component design and certification. By understanding the distinctions between protected and unprotected systems, and by ensuring compliance through appropriate certification pathways, engineers and contractors can effectively mitigate risks associated with A2L refrigerants. Staying informed and adhering to established safety standards will be pivotal in navigating this transition successfully.​

---

At the PES Design Group our mission is: “Designing functionally innovative, attractive and profitable c-store and food service facilities on time and on budget”.  Our promise to you is, that whatever your project may be, we will approach it as unique.  We will use our years of experience to design innovation and uniqueness into your project helping you to set yourself apart from the rest. We will also use innovation to solve challenging issues such as space, time and budget constraints.

About the Consultant

 

Jim Richards (Jr) is President of and Food Service Consultant with PES Design Group. During his 30+ years of experience in the Food Service Design Industry, Jim has encountered countless design challenges that he has successfully overcome through experience, innovation and a wealth of knowledge about efficient kitchen design and foodservice equipment.

Call us today for a FREE consultation about your project! 800.850.6638