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The race is on to replace high GWP refrigerants by low and medium GWP alternates.
Pressure on High GWP Refrigerants
There is growing pressure to limit and phase-out high GWP refrigerants in some countries as well as globally with talk of including HFCs within a phase-down plan under the highly successful Montreal Protocol.
High GWP commercial refrigeration refrigerants R404A and R507 with GWPs of around 3300 are being phased out in both Europe and the US over the next few years. The emergence of low/medium GWP alternatives is putting pressure to move to these new refrigerants. Even R134a with a GWP of 1430 is being replaced in European vehicle air conditioning systems by R1234yf (GWP of 4). R410A with a GWP of 2088 continues on, but for how long?
R-410A Concerns
Refrigerant manufacturers and HVAC OEMs have concluded that R410A will not survive.
R410A use began in the mid 1990's in Europe. It has grown in popularity globally in products from mini-splits to large screw chillers and most equipment in between. It is not used in centrifugal chillers. R410A is the dominant refrigerant in air conditioning systems today.
Replacing it in some, or all, of its applications is the target for today's HVAC industry.
Industry Taking Action
Refrigerant manufacturers, Chemours, Daikin, Honeywell, Arkema, Mexichem and others have come out with their own (proprietary) designs of alternatives to replace R410A. A second look is also being given to some previously discarded alternatives such as R-32 which was rejected as a replacement for R-22 in the 1990's due to non-compliance with flammability regulations in effect at the time. R-32 was eventually combined with (non-flammable) R-125 in a 50/50 mixture that was named R-410A and has well served the industry for two decades.
Since the introduction of R410A a new safety classification of "mild" flammability, A2L,has been developed which allows them to be treated with different regulations. Most of the currently proposed alternatives are A2L, including R32. This new classification has allowed the introduction of R32 and other mildly flammable blends in small charge applications such as window air conditioners and mini-splits.
Battle Lines Being Drawn
The competitive lines are being drawn with one camp promoting R32 as the preferred alternative. Daikin, a manufacturer of R32 as well as an OEM, promotes, manufactures and sells R32 units leading the way with most Japanese OEMs also manufacturing and promoting R-32 units. Daikin offers R32 units in Europe as well as a number of developing countries. In an effort to gain new R-32 supporters Daikin recently offered free access to 93 separate patents pertaining to the use or application of R32 to companies worldwide. Further efforts by Daikin include providing technical assistance and training to emerging economies such as Thailand to adopt R32 for their markets with funding from the Montreal Protocol.
The other camp is led by Chemours (formerly DuPont) promoting DR55, a blend of 67% R32, 7% R125 and 26% R1234yf, which it will market as Opteon XL55. Trane partnered with Chemours in recently displaying an air cooled chiller in Japan using DR55 and said they were also investigating its use in unitary and residential equipment. Chemours goes further, describing DR55 as being suitable for residential, light commercial and commercial window units, portables, mini-splits, ducted splits, PTACs, commercial packaged, multi-splits and DX chillers.
"With a GWP of only 676 DR55 is said to be the most optimized low GWP replacement for R410A, achieving a 5% energy efficiency improvement. It is also said to offer excellent performance in high ambient conditions and has a low temperature glide of just -1K." "XL55 (DR55) delivers improved energy efficiency, 67% GWP reduction as compared to R410A, ultra-low flammability properties, excellent performance at high ambient temperatures, and easy conversion from existing R410A designs due to very close physical properties,".
Although DR55 has the same A2L "mildly flammable" classification as R32, Chemours maintains that some global OEMs have indicated that the lower flammability properties of XL55 are compelling and are likely to be an important consideration in product selection, especially for larger charge size equipment.
Refrigerant Blends
Other refrigerant manufacturers including Honeywell, Arkema and Asahi Glass are touting the advantages oftheir unique formulations, which in some cases, contain new HFO molecules. Each component and composition is carefully optimized to create advantage in a (range of) applications. Quantifying (or monetizing) the differences and advantages/disadvantages compared to other alternatives in each application will challenge building owners, manufacturers, lawyers and the service industry for years. (Follow the links below for more details on this complex issue).
Mildly Flammable Refrigerant Use
Clearly there is, and will continue to be, a major movement into the use of mildly flammable A2L refrigerants in our industry. Revisions in safety standards that are currently being implemented are expected to allow charges of up to 60 kg.
Refrigerant Blending and Optimizing
It is unclear at this time how many winners and losers there will be, or how many different replacements there will be to R410A. What will the industry do with this newfound ability "to tradeoff some efficiency for a little less high ambient performance and a little flammability increase"? How will we value a GWP reduction from 300 to 100?
We can continue to wonder just how far we may go with the technology of customized blending of refrigerants. Anyone in the HVACR industry will need to consider this a core technology for their business.
Read more now from one of the UK's leading information sources, oCooling Post.
Is DR-55 Best Option to Replace R410A?
Daikin Gives Free Access to R32 Patents
Daikin Leads Thailand's Switch to R32
What Future for R410A?
Trane Debuts R410A Replacement
Editor's Note: CR4 would like to thank GEA Consulting's President, Larry Butz,, for contributing this blog entry, originally appearing at http://www.gea-consulting.com/hvac-blog
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