Energy Savings Opportunity
Rooftop units are commonly used to provide space heating and cooling because they offer many benefits. Rooftop units are relatively inexpensive and can easily be integrated into a standard forced air duct system when placed on the exterior of a building; so they don’t take up valuable internal space. You can save on operating costs by installing a high efficiency rooftop unit in a new building, replacing old, inefficient rooftop units in existing buildings, as well as by maintaining your HVAC system. If you have a failed unit that needs to be replaced, buying an energy efficient model will provide savings over the life of the unit. For example, if you replace an existing 5 ton 9 SEER unit with a high efficiency 5 ton 12 SEER unit, you may pay more up front than for a standard model, but you can save considerably on energy costs over the life of the unit plus save on maintenance costs.

High Efficiency Rooftop Units
The energy efficiency of rooftop units 5.5 tons and smaller is listed in terms of SEER (Seasonal Energy Efficiency Ratio), while the efficiency of units over 5.5 tons is listed in terms of EER (Energy Efficiency Ratio). Currently, ENERGY STAR® and FEMP (Federal Energy Management Program) consider a unit of 5.5 tons or
smaller with a SEER of 12 or higher to be efficient, and consider a unit larger than 5.5 tons with an EER of 11 or higher to be efficient. Smaller units will soon be given an EER in addition to a SEER to ensure that peak day performance
can be judged for these units. Over the years, the average efficiency of rooftop units has increased. In 1981, the average SEER was about 7.8, but by 1995, the average had jumped to about 10.7. In addition, as a unit gets older, its parts become worn and efficiency decreases. Thus, that 1980’s vintage rooftop
unit might really have a SEER of less than 7.0 when wear-and-tear on its parts is taken into account.

Maintenance
Keep your rooftop unit in top condition by changing the filters every spring and fall, and having it serviced at least once a year. Servicing should include greasing the bearings and checking pulleys, belts, refrigerant charge, temperature drop across the coil and amperage for potential problems.