The Allegiance 16 actually has two compressors. Most of the time this air conditioning unit will operate at low speed, providing quiet, even comfort for your home. This single stage is also extremely efficient, giving you increased energy savings. However, on extremely hot days when more cooling is required, the Allegiance 16 switches to the second stage. With two stages of cooling, your level of comfort is always maintained, regardless of the weather or extremes in temperature.

With SEER ratings up to 17.20!

Every major component in the TCH Over/Under Single Package Air Conditioner is built to a higher standard. Even during the hottest days of summer, American Standard's TCH will keep your home comfortable. The over/under air discharge design of the TCH makes it easy to install. With cooling and air handling in the same unit, the TCH can either be flush mounted beside your house at ground level, or the roof for horizantal airflow.

And as always, American Standard's excellent extended warranties make unplanned repair bills a thing of the past.