Two-stage cooling allows the 4SCU16LS to adapt its output to match demand' so your temperature stays exactly where you set it. Two-stage cooling also helps the 4SCU16LS save energy' because it can run at a lower' more efficient speed most of the time and ramp up cooling output as needed for the hottest days. By adjusting its cooling output' the 4SCU16LS can even give you greater control over humidity' to preserve the quality of your air. It’s the air conditioner built to offer more. Because it’s built for life. Yours.