From inside (document excerpt):
24APA7 Performancet Series 17 2 Stage Air Conditioner with Puronr Refrigerant 2 to 5 Tons Product Data INDUSTRY LEADING FEATURES / BENEFITS Efficiency S 17 SEER / 11.5 — 13.0 EER S Microtube Technologyt refrigeration system S Indoor air quality accessories available Sound S Sound level as low as 72 dBA Comfort S System supports Infinityt Control or standard 2–stage thermostat controls Reliability S Puronr refrigerant — environmentally sound, won’t deplete the ozone layer and low lifetime service cost.
the environmentally sound refrigerant Carrier’s Air Conditioners with Puronr refrigerant provide a collection of features unmatched by any other family of equipment. The 24APA7 has been designed utilizing Carrier’s Puron refrigerant. The environmentally sound refrigerant allows you to make a responsible decision in the protection of the earth’s ozone layer. As an Energy Starr Partner, Carrier Corporation has determined that this product meets the Energy Starr guidelines for energy efficiency. Refer to the combination ratings in the Product Data for system combinations that meet Energy Starr guidelines. NOTE: Ratings contained in this document are subject to change at any time. Always refer to the AHRI directory (www.ahridirectory.org) for the most up- -date ratings -toinformation. S Front–seating service valves S 2–stage scroll compressor S Internal pressure relief valve S Internal thermal overload S Low pressure switch S High pressure switch S Filter drier S Balanced refrigeration system for maximum reliability Durability WeatherArmort protection package: S Solid, Durable sheet metal construction S Steel louver coil guard S Baked–on, complete outer coverage, powder paint Applications S Long–line — up to 250 feet (76.2 m)