A rooftop home comfort system (known as a "packaged unit") has a furnace/air handler (which heats and circulates the indoor air) and an air conditioning unit, all packaged into one rooftop unit. Packaged units are easy to install and an economical choice for replacing an existing packaged system, or new home. Packaged units can be changed out in as little as a single day.

The Seasonal Energy Efficiency Ratio (SEER) is a measure of the cooling efficiency of your air conditioner. The higher the SEER number, the more efficient the system (similar to gas mileage in a car). The heating ability is measured with an Annual Fuel Utilization Efficiency (AFUE) percentage. Basically an 80% AFUE packaged unit will utilize 80% of the heat generated, to warm the indoor air.