RS-44 (R-424A) is one of several new refrigerants from ComStar International for retrofit applications.

COLLEGE POINT, N.Y. - Three new HFC refrigerants that work with mineral oil and, according to published reports, have A-1 safety ratings, are entering the U.S. market from ComStar International Inc. The safety rating documentation clarifies information published in the Jan. 15 issue of The NEWS. The refrigerants are RS-44 (ASHRAE designation of R-424A), RS-24 (R-426A), and RS-52 (R-428A).

According to the company, R-424A “is a nonflammable blend of R-125, R-134a, n-butane, isobutene, and isopentane, which has zero ozone depletion potential [ODP] and is also compatible with both traditional and synthetic lubricants. [The refrigerant] is suitable for use as a replacement for R-22 in new and existing commercial and industrial air conditioning and refrigeration systems as well as appliances.”

R-426A “is a nonflammable blend of R-134a, R-125, butane, and isobutene,” with the same zero ODP and for use with both mineral oils and synthetic lubricants. The refrigerant “can be used in all the main applications where R-12 is present, including hermetic and semihermetic compressor systems, cold stores, refrigerated transport, and dairy chillers.”

R-428A was described as suitable for use in applications where R-22, -502, -402A, and other refrigerants “are commonly found, including supermarket display cases, ice machines, cold storage, transportation of foodstuffs, freezer cabinets, freeze dryers, and environmental test chambers.”

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Publication date:03/12/2007