The Infinity® 98 furnace delivers precision comfort with Greenspeed™ intelligence. This is the most advanced Carrier® furnace ever made. Its unique design innovations achieve unprecedented efficiency and quiet. Greenspeed intelligence is created by pairing adaptable-speed technology with our Infinity control’s intelligence. The unique, modulating gas valve of this unit, when managed by Infinity control, allows it to literally adapt its output to the needs of the home. With tiny, 1% adjustments between 40 and 100% capacity, it gives the home only the amount of heating necessary.