From inside (document excerpt):
24ANB7 Infinityt 17 2 Stage Air Conditioner with Puronr Refrigerant 2 to 5 Nominal Tons Product Data INDUSTRY LEADING FEATURES / BENEFITS Efficiency S 14 — 18 SEER / 11.5 — 13.7 EER S Microtube Technologyt refrigeration system S Indoor air quality accessories available Sound S Sound level as low as 69 dBA S Quiet mount split post compressor grommets S Forward–swept condenser fan blade S Compressor sound hood S Laminated steel compressor mounting plate S 8 pole PSC ball bearing outdoor condenser fan motor 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.
Carrier’s Air Conditioners with Puronr refrigerant provide a collection of features unmatched by any other family of equipment. The 24ANB7 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. This product has been designed and manufactured to meet Energy Starr criteria for energy efficiency when matched with appropriate coil components. 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 Crankcase Heater standard S Balanced refrigeration system for maximum reliability Controls and Diagnostics S Infinityt control (Dedicated A,B,C,D only) S Utility Interface Connection S Up to 18 point diagnostic capability Durability WeatherArmort protection package: S Solid, Durable sheet metal construction S Steel louver coil guard S Baked