The "S" Series A/C unit features a multi-step capacity compressor with green refrigerant R410A, and is ideal for new construction, modular applications, school modernization, and telecommunication structures. The units are available in 3 to 5 ton with EER ratings up to 11.7 and integrated part load value efficiency up to 15.2 Btu/W. Additional features include an ECM indoor blower motor, dual-pressure controls, compressor control module, and step-capacity scroll compressor. Ventilation packages are available, ranging from economizers to an ERV with a capacity of 450 cfm.