摘要 |
<p>A heat transfer composition comprises up to about 30 % by weight carbon dioxide (R-744), from about 30 % to about 80 % by weight difluoromethane (R-32), and 1,3,3,3-tetrafluoropropene (R-1234ze), preferably R-1234ze(E). The composition preferably has a low GWP and may further comprise a lubricant, a stabiliser or a flame retardant. The composition may be a refrigerant, a blowing agent, a foam or a sprayable composition. The composition may be used in a heat transfer device e.g. automotive air conditioning systems, chiller refrigeration systems. Also shown are methods of cooling, heating, extraction and cleaning using the composition.</p> |