Enjoy Cozy, Quiet, Efficient Heat for Years to Come with a Gas-Fired Boiler.

Gas-fired water boilers deliver comfortable, even heat very little noise. What’s better is their high-level energy efficiency. At Twin Air LLC in Manassas, many of the Lennox® gas-fired water boilers we sell are ENERGY STAR® qualified.

Learn about the features of our high-efficiency boilers.

GWM-IE Boiler

This gas-modulating condensing water boiler is ENERGY STAR® qualified and 40% more efficient than conventional boilers. Not surprisingly, it carries a 95% AFUE rating.* To boost fuel savings, it is equipped with an electronic ignition control that turns on the burner to coordinate with your household demand to ensure it uses only the energy it needs to keep your family warm.

  • Strong, self-cleaning, stainless steel heat exchanger turns waste energy into usable heat
  • Sealed combustion minimizes noise
  • Modulating capability perfectly meets your comfort needs by allowing the burner to fire at as low as 20% of its capacity
  • Stainless steel mesh burner fights corrosion and oxidation
  • CPVC flue condensate collector is corrosion-resistant and removes the use of metal in the venting area.
  • 15-year limited warranty on heat exchanger, 10-year limited warranty on remaining covered components
GWM-IE Boiler
Efficiency Rating (AFUE): up to 95
Energy Star badge

GWB9-IH Boiler

The GWB9-IH boiler effortlessly integrates with a traditional radiator system and is ENERGY STAR qualified with an AFUE rating of 90%.* Its cast-aluminum heat exchanger transfers heat quickly—as much as three times faster than a traditional cast-iron exchanger.

  • Enduring, heavy-gauge steel cabinet with baked-on paint finish
  • Compact design for installation flexibility
  • Sealed combustion reduces noise
  • Electronic ignition oversees water temperature and ignites the burner only when necessary
  • Burns natural gas or can convert to LP gas
  • 15-year limited warranty on heat exchanger, 10-year limited warranty on remaining covered components
GWB9-IH Boiler
Efficiency Rating (AFUE): up to 90
Energy Star badge

GWB8-IE Boiler

Significantly more efficient than an older boiler, the GWB8 boiler has an 84.4% efficiency rating*—it also works with older radiator systems.

  • Electronic ignition monitors water temperature and turns on the burner only when needed
  • Thick fiberglass insulation greatly reduces off-cycle heat and energy loss
  • Cast-iron heat exchanger and titanium burners designed for years of reliability
  • Available in six different sizes for ultimate installation flexibility
  • Burns natural gas or can convert to LP gas
  • 20-year limited warranty on heat exchanger, 1-year limited warranty on remaining covered parts
GWB8-IE Boiler
Efficiency Rating (AFUE): up to 84.4

GWB8-E Boiler

Built with a long-lasting cast-iron heat exchanger and durable stainless steel burners, this standard-efficiency boiler can perform year after year.

  • Electronic ignition monitors water temperature and turns on the burner only when needed
  • Thick fiberglass insulation greatly reduces off-cycle heat and energy loss
  • Works with older radiator systems
  • Offered in nine different sizes for installation anywhere in your home
  • Burns natural gas or convertible to LP gas
  • 20-year limited warranty on heat exchanger, 1-year limited warranty on remaining covered parts
GWB8-E Boiler
Efficiency Rating (AFUE): up to 83.9

Reach us at 703-754-1062 or schedule an appointment online so our team at Twin Air LLC in Manassas can help you find the right boiler for you, or fix your boiler so it is running as it should.