Multi-Stage Air Conditioner
Money Savings
5-Year Savings in dollars
10-Year Savings in dollars
15-Year Savings in dollars
Energy Saving Per Year Based on US National Average
  • Up To 21 SEER Energy Efficiency*
  • Quantum Coil*
  • Two-Stage Compressor*
  • Sound Rating as low as 69 dB
  • Energy Star Certified*
  • Home Humidity Higher Removal Rate
  • iComfort®-Enabled
  • 10-Year Limited Warranty on Compressor and Covered Components*
Seasonal Energy Efficiency Ratio (SEER)

This rating determines an air conditioner’s efficiency. The higher the SEER rating, the more energy-efficient it is.

Quantum™ Coil

Lennox exclusive coil is made from a proprietary aluminum alloy for improved resistance to corrosion, resulting in improved performance and energy savings.

ENERGY STAR® Certified

HVAC equipment with the ENERGY STAR label meets or exceeds federal guidelines for energy-efficient performance.

10-Year Limited Warranty on Compressor and Covered Components

Covered components may be eligible to receive a 10-year warranty. Online equipment registration at is required within 60 days of installation (except in California and Quebec) or Lennox’ base warranty will apply. Applies to residential applications only. See actual warranty certificate for details.

Benefits and Features

  • SilentComfort™ technology for peace, quiet and comfort
  • Reinforced with a PermaGuard™ cabinet for long-lasting protection against rust
    and corrosion
  • SmartHinge™ coil protection for easy coil cleaning
  • iComfort®-enabled for easy control at your fingertips

Comfort and Efficiency Come Together Perfectly

The XC21’s multi-stage operation allows it to fine-tune your cooling, humidity levels and energy use by matching output to demand.

Cooling That Goes Beyond Temperature Control

Humidity levels can drastically affect how the air in your home feels. It can make the air feel up to 8 degrees warmer than the actual temperature. By working with the Humiditrol® whole-home dehumidification system, the XC21 can preserve your comfort in every way.

Industry-Leading Efficiency

With efficiencies of up to 21.00 SEER, the XC21 can lower your energy bills by hundreds of dollars a year, while still keeping your home cool and quiet.

Up to 20% Quieter Than a Standard Air Conditioner

The XC21 uses SilentComfort™ technology to reduce operating noise, making it the quietest multi-stage air conditioner you can buy. Even when installed outside a bedroom window, it lets you rest peacefully.