Refrigerant R32: Friend or Foe?

by

Summary

With rising concerns over the environmental impact of refrigerants, R32 has emerged globally as the dominant choice in the transition to lower-GWP (Global Warming Potential) solutions. Despite initial industry resistance, it offers improved energy efficiency, reduced environmental impact, and greater affordability compared to legacy refrigerants like R410A. 

Lay people may not be aware that R410A is 50% comprised of R32. 

This article explores: 

  • concerns over flammability, system compatibility, and long-term viability.
  • lower GWP, improved efficiency, and better recyclability, and 
  • why we should embrace R32, with a pragmatic approach to future-ready refrigerant selection. 

Setting the Stage

Australia is a population that has held the title of world’s greatest uptake per capita of air conditioning. With the global drive towards Net Zero, engineers are navigating a significant transition with the rise of A2L-classified refrigerants, particularly R32.  

With a Global Warming Potential (GWP) of 675, R32 offers a marked improvement over traditional refrigerants like R410A (GWP 2088) and is increasingly being adopted in residential and light commercial applications. It has limitations though. 

What many readers may not realise is that R410A is a blend consisting of 50% R32 and 50% R125—meaning R32 has already been in use for decades. It is already in use in “small-charge scenarios” such as car air-conditioning, and refrigerators within Australia. 

Despite concerns over mild flammability, its higher energy efficiency, lower GWP, and recyclability advantages make it a compelling choice for HVAC professionals. Yet large scenarios need to be avoided or carefully planned. 

Understanding A2L Refrigerants: What Makes R32 Different?

Refrigerants are classified by flammability (A or B) and toxicity (1, 2, or 3) under AS/NZS 5149.1:2016. Traditional refrigerants like R410A and R134a are A1-classified, meaning non-flammable and non-toxic. In contrast, R32 is A2L, meaning low toxicity with mild flammability. 

Comparing key properties of R32 to R410A:

Property R32 R410A
GWP 675 2088
Ozone Depletion Potential 0 0
Efficiency Higher Standard
Flammability Rating A2L (Mildly Flammable) A1 (Non-Flammable)
Composition Single Component Blend (R32/R125)

One major engineering advantage of R32 is that it is a single-component refrigerant, making it easier to recover and recycle compared to refrigerant blends like R410A, which suffer from fractionation (where the components separate over time).

Industry Concerns – Flammability & Safety Regulations

The main concern with R32 is its A2L classification, which indicates mild flammability. While R32 can ignite under specific conditions, its burning velocity is significantly lower than hydrocarbons like propane (R290). Whilst it is actually very difficult to ignite, work must be undertaken in a well ventilated environment.

Figure 1 Don’t be tempted to ignore flammability even though some crazy YouTube guys could not light R32 with a burner.

Our legal obligations demand we treat the mild flammability risks of R32 properly – all work should be undertaken in a well-ventilated area, all pipework should be capable of inspection, no unit should be located within 300mm of a power point or ignition source.

Mitigating flammability risks:

  • Leak Detection Systems – Ensuring compliance with AS/NZS 5149.3 for risk assessment.
  • Proper Ventilation – Mandated for enclosed machine rooms and commercial spaces.
  • Charge Size Limits – AS/NZS standards specify limits for safe refrigerant quantities in different applications.

In the infographic below, we compare the refrigerants that are available now with their density and GWP. The density is a valuable parameter as it reflects the refrigerants impact on unit cost-effectiveness. Thus the dense refrigerants that permit cost effective unit production and have low GWP are also unfortunately tending to be more flammable.

Figure 2 Source: Danfoss

System Compatibility & Equipment Considerations

Since R410A is already 50% R32, most existing system components (compressors, condensers, expansion valves) can be adapted with minor modifications. However, differences in pressure and oil compatibility must be considered:

  • R32 operates at higher discharge temperatures, necessitating oil formulations that prevent compressor overheating.
  • Some older systems may require specific electronic expansion valves to optimise performance.

Long-Term Viability: Is R32 a Stopgap Solution?

Unfortunately, R32 also has a “phase-down” schedule. While R32 is not the final refrigerant solution, it serves as a transitional step toward ultra-low GWP refrigerants. Future options like R1234yf (GWP < 1) and natural refrigerants (CO₂, ammonia)are promising, but adoption barriers such as cost, toxicity, and infrastructure limitations mean R32 will remain dominant for at least the next decade.

One key disadvantage is that only 1 VRF manufacturer has a solution that addresses the large charge problem with R32. Hence, VRF systems will be more costly until more manufacturers respond to this challenge.

Sustainability Advantages of R32

Lower GWP & Environmental Benefits

  • R32 has a 67% lower GWP than R410A, aligning with global climate goals.
  • Ozone-friendly: Unlike older refrigerants (e.g., R22), R32 has an ODP of 0.
  • Less refrigerant charge required – 30% less R32 is needed to achieve the same cooling capacity as R410A, further reducing emissions.

Figure 3 Source: Daikin

Energy Efficiency Gains

  • R32 is up to 10% more efficient than R410A, leading to lower power consumption and improved seasonal energy efficiency ratios (SEER).
  • Systems using R32 can achieve better performance at high ambient temperatures, making it well-suited for Australia’s climate.

Recyclability & Serviceability

Unlike blended refrigerants that require complex separation processes , R32 is a pure refrigerant , making it:

  • Easier to recover and reuse from decommissioned equipment.
  • More cost-effective for HVAC service providers who no longer need to dispose of mixed refrigerant blends.
  • The process for R32 has a much easier pathway to reclaim and reuse refrigerant within new equipment. The process is presented below:

Figure 4 Source: “Life-Cycle Assessment of Refrigerants for Air Conditioners”. Yoshihito Yasaka , Selim Karkour , Koichi Shobatake , Norihiro Itsubo and Fumiaki Yakushiji

Why We Should Embrace R32: A Pragmatic Transition Approach

Australia’s refrigerant transition must balance environmental goals, economic feasibility, and engineering practicality. While long-term refrigerant solutions will continue evolving, R32 offers the most viable path forward today.

  • Regulatory Alignment: Australia’s phasing down of high-GWP refrigerants under the HFC Phase Down Program (2018–2036) requires viable, immediate alternatives—R32 fits this need.
  • Industry Acceptance: Leading manufacturers (Daikin, Mitsubishi, Fujitsu) have already transitioned their split system air conditioners to R32, with commercial adoption expanding. Some VRF models are only just now coming to market.
  • Minimal Retrofit Costs: Many R410A systems can be easily adapted to R32, allowing for gradual adoption without massive infrastructure investments.
  • Improved recycled rate. The energy and cost to recover R32 is less than half of that to destroy R32 and less than 15% of that required to create R32. By comparison, the reclamation or production of R410A is 3x to 4x higher in energy and economy than R32 reclamation due to the difficulty of blending component refrigerants in R410A. The complexity of the blend is where the cost and energy is being spent.

Recommendations for Engineers & Building Owners

  • Consider R32 for all new HVAC projects where possible.
  • For Large Volumes, incorporate leak detection and proper ventilation to meet charge limitations.
  • Have designers stay informed on AS/NZS refrigerant regulations to ensure compliance in design and installation.

Conclusion

The transition to A2L refrigerants, particularly R32, is an essential step in reducing the environmental impact of HVAC systems. While concerns over flammability and compatibility persist, engineering solutions exist to mitigate risks effectively.

It is not our intention to sell anything here, however SEED has developed charge modelling software that can assist with large charge systems of R32 if you do get into trouble.

A typical image is presented below:

We encourage members to be “alert but not alarmed” with R32 proposals.