The technology in a two-speed / two-stage furnace enables a gas furnace to improve indoor air circulation and overall comfort, while reducing operating noise. It operates at a slower, more consistent level over 90 percent of the time. This means lower temperature swings and less of the cold drafts that are associated with single-speed furnaces.
Variable-speed furnaces feature the best technology and are the quietest furnaces in the industry today. The blower motor ramps up gently, quietly, and economically to provide a nearly continuous flow of warm air in a low-capacity operation, maximizing your comfort. The blower motor uses only an eighth of the power of a standard furnace blower motor. It also increases efficiency in your air conditioning system up to 10 percent.