From inside (document excerpt):
24ACA3 ComforttSeries 13 Air Conditioner with Puronr Refrigerant Product Data INDUSTRY LEADING FEATURES / BENEFITS Efficiency S 13 SEER/11.0 EER (nominal) S Microtube Technologyt refrigeration system S Indoor air quality accessories available Sound S Sound level as low as 74 dBA S Compressor sound blanket Comfort S System supports Thermidistatt or standard thermostat Diagnostics S TechAssistt with 6–step diagnostics at–a–glance Reliability S Puronr refrigerant — environmentally sound, won’t deplete the ozone layer and low lifetime servce cost.
(Single-Phase Only) controls A04030 the environmentally sound refrigerant S Front–seating service valves S 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: Carrier’s Air Conditioners with Puronr refrigerant provide a collection of features unmatched by any other family of equipment. The 24ACA 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. S Solid, Durable sheet metal construction S Steel louver coil guard S Baked–on, complete coverage, powder paint S Color matched ceramic coated screws Applications S Long–line — up to 250 feet total equivalent length, up to 200 feet condenser above evaporator, or up to 80 ft. evaporator above condenser (See Longline Guide for more information.) Low ambient (down to -20_F) with accessory kit S Warranty S Single-Phase: 10 year limited compressor warranty 5 year limited parts warranty Three-Phase: 5 year limited compressor warranty 1 year limited parts warranty MODEL NUMBER NOMENCLATURE 1 N 2 Product Series 24=AC 2 N 4 3 A A Product Family A=RES AC 4 A C Tier 5 A/N A Major Series 6 N 3 SEER 3=13 SEER 7 N 3 8 N 6 9 A/N A Variations A=Standard 10 A/N 0 Open 0=Not Defined 11 A/N 0 Open 0=Not Defined 12 N 3 Voltage 3=208/230 1 5=208/230 3 6=460 3 13 N 0 Minor Series 0, 1, 2. Cooling Capacity C=Comfort A=Puron ISO 9001:2000 24ACA3 the environmentally sound refrigerant REGISTERED As an Energy StarĀ® Partner, Carrier Corporation has determined that this product meets the ENERGY STARĀ® guidelines for energy efficiency. Refer to the combination ratings in Product Data for system combinations that meet Energy Star guidelines.