The Lennox XC21 was introduced this year during the National Dealer Meeting in Nashville, Tenn. According to Lennox, it is approximately 13 times quieter than a standard air conditioner. The unit has a two-stage compressor that runs at low speed 80 percent of the time, providing a more consistent comfort environment. This 20.5-SEER air conditioner operates with chlorine-free R-410A refrigerant. It continuously monitors system performance with the Lennox system operations monitor, the first onboard cooling system diagnostics in the industry, says the company.

The thermidistat control on the Lennox XC21 allows for humidity and temperature to meet simultaneously. According to Kobie Kooling Inc., this yields an approximate 50 percent reduction in utility bills.