R466A confirmed as inert by Japanese refrigeration society

USA: The Japan Society of Refrigerating and Air Conditioning Engineers (JSRAE) has recognised R466A, Honeywell’s lower GWP, non-flammable alternative to R410A, as a “new inert refrigerant.”

The recognition confirms ASHRAE’s previous classification of R466A as an A1 (no flame propagation, lower toxicity) refrigerant.

Branded by Honeywell as Solstice N41, the refrigerant created huge interest when first announced in 2018. Although not a retrofit gas, its non-flammable characteristics and lower GWP of 733 make it, at least, a potential medium-term replacement for R410A in the popular VRF systems. 

“Solstice N41 is a safe and economical solution for original equipment manufacturers in Japan and around the world who are seeking to replace R410A with an energy-efficient solution that is safe for the environment, without sacrificing performance,” said Chris LaPietra, vice president and general manager, Honeywell Stationary Refrigerants. “We specifically developed Solstice N41 to address the many regulatory and safety issues facing the industry, and its recognition by JSRAE will enable further global development as we move towards commercialising this solution.”

The refrigerant was originally going to be available in commercial quantities in the fall of 2019, then early 2020.  A number of OEMs were initially reported to be working with R466A, including Chinese manufacturer Midea and Toshiba Carrier – a company which described the new refrigerant as “promising” after initial performance testing in a VRF air conditioning system. Component manufacturers Sanhua and Parker Hannifin were also known to be carrying out compatibility testing. 

There have, however, been rumours of stability and compatibility concerns related to the refrigerants blend’s key flammability suppressing component CF3I (R13I1). Honeywell has denied any problems, telling the Cooling Post that the stability and shelf-life can be addressed with standard measures practiced in the industry.

As we approach the third anniversary of the initial announcement of the refrigerant, Honeywell maintains that R466A is now in the “advanced stages” of commercialisation. According to Honeywell, it is currently being extensively tested by over 15 OEMs and leading compressor manufacturers, including OEMs in Japan. It is also said to have accumulated more than 100,000 hours of testing in different applications such as commercial AC (VRF and rooftops) and residential AC (unitary ducted equipment in the USA). “In Japan, the JSRAE designation is a key milestone for VRF OEMs to phase down HFCs in these applications,” Honeywell says.