The 581J is available in 3 to 25 ton single packaged rooftops that are ASHRAE 90.1 energy compliant and Energy Star® certified. These gas heating/electric cooling units offer up to 15.6 SEER cooling efficiency and up to 82% AFUE heating performance. Customize them with a full line of factory options or field-installed accessories. Single- and multi-stage cooling and heating models are available with a variety of heating sizes for each unit size.