Carrier manufactures 13 different models of split system air conditioner units as of 2015. Carrier offers three different air conditioner product lines: the Infinity, Performance and Comfort Series.
The Carrier Infinity Series contains the high-end models, which are more efficient and more expensive than the other two lines. These models have seasonal energy efficiency ratings, or SEER, that range between 16 and 21, while also providing the highest level of comfort of all Carrier air conditioners. These models are also the quietest units Carrier produces, averaging between 56 and 67 decibels.
The Carrier Performance Series is the company's middle of the line product range, containing five models that range in efficiency from 13 up to 17 SEER. The Comfort Series contains three models that range in efficiency from 13.2 to 16.5 SEER, which still places them above the minimum allowable efficiency rating stipulated by the U.S. Department of Energy.
Many of the Carrier air conditioners are federal Energy Star rated, including the Infinity 21, which was named as a Best Buy by Consumer Digest. This model comes with a 10-year limited parts warranty and features Carrier's trademark non-ozone depleting Puron refrigerant. The Infinity 21 uses a two-stage compression system, which increases energy efficiency by allowing the unit to run in low-stage for the majority of the time.