Improved Energy Efficiency
While rooftop unit models are available in SEER and AFUE ratings, they have plenty of energy efficient properties before purchasing these options. They typically provide heating and cooling for a smaller part of your building, giving you individualized control over the usage. If one space is empty for certain hours, but another is in use, you can adjust the schedule instead of running the full system.
Rooftop units also use outdoor air to control the indoor temperature through ventilation only possible on the roof. This means it uses less refrigerant than a standard HVAC system, requiring less from the motor.