... room air Cooler produced by Chenguang includes BDF,LZW FD Series,ceiling and floor types to Ammonia and Freon refrigeration system. ... BDFand LZW series with aluminum pipe and fins are chiefly designed forammonia system ... purpose of freon system. Refrigerants: R717(BDF,LZW series), R22,R404a,R507C(FD series)Material: aluminum pipes and fins for ammonia, ...