COLLEGE POINT, N.Y. - Four HFC refrigerants that can work with mineral oil and have long been available in Europe are now coming to the U.S. market through ComStar, a distribution company.

It has announced it is distributing RS-24 (R-426A), RS-44 (R-424A), RS-45 (no American Society of Heating, Air-Conditioning, and Refrigerating Engineers (ASHRAE) designation as yet), and RS-52 (R-428A). Refrigerant Solutions Ltd. (RSL) of Cheshire produces the refrigerants in England. They are a blend of various HFC refrigerants as well as a small percentage of pentane, butane, and/or isobutene.

According to ASHRAE officials, the refrigerants have yet to be assigned a safety rating.

All four refrigerants are designated HFC alternatives to CFC and HCFC refrigerants. CFCs have not been allowed in new equipment for a number of years, and HCFCs are currently being phased out for use in new equipment. A great deal of equipment, however, is currently running with phased-out refrigerants or those about to be phased out. ComStar and RSL said its RS refrigerants have OEM and retrofit applications. In the retrofit category, they are promoted as a means to keep older equipment running as contractors face shortages of CFCs and HCFCs.

RS-24 was said to be an alternative to R-12; RS-44 was said to be an alternative to R-22; RS-45 as an R-22 replacement; and RS-52 as a replacement for R-22 and R-502 in low-temperature applications.

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Publication date:01/15/2007