A method of cooling the bearings of a motor in a motor housing for a furnace assembly is disclosed comprising an aperture in the motor housing whereby air is brought into the motor housing and drawn around the motor via an impeller into the impeller housing thereby eliminating the need of a separately attached fan to cool the motor or motor bearings. The impeller pulls the air from the motor housing into the impeller housing or blower via an inlet port in the impeller housing and apertures in the back plate of the impeller and out an exhaust port situated in the impeller housing.