A Trane furnace uses specially shaped burners and an innovative gas valve to create more heat from less fuel, and a highly efficient fan motor to circulate air. As part of a matched Trane system, a Trane Xl80 Furnace Manual - mail.trempealeau.net Trane XR80 Furnace Overview Trane’s XR80 is a single stage gas furnace with an AFUE of up to 80%.