Basic model of federally regulated packaged terminal air conditioner (PTAC) or packaged terminal heat pump (PTHP)

means all units manufactured by one manufacturer within a single equipment class, having the same primary energy source (e.g., electric or gas), and which have the same or comparable compressors, same or comparable heat exchangers, and same or comparable air moving systems that have a cooling capacity within 300 Btu/h of one another.