Package units are designed as a complete outdoor unit with both heating and cooling capability. Package unit range from 14 SEER to 16 SEER cooling and 8.0 – 8.5 HSPF rating. The HSPF rating (Heating Seasonal Performance Factor) is the ratio of heat energy delivered to electrical energy supplied. The higher the HSPF rating the higher the heating efficiency rating. The higher the SEER rating the higher the cooling efficiency rating.