Apparatus for measuring the temperature of a nozzle having fluid material injected from an injection molding machine through a flow channel in a heated manifold that is coupled to a nozzle that is coupled to the cavity of a mold, the apparatus comprising: a heating device comprising a controllably heatable thermally conductive heating element; the heating element of the heating device being mounted on or around the outer surface of the tube of the nozzle at an end point; a temperature monitor comprising a temperature sensor mounted on or around the nozzle at a selected position along the axis of the bore of the nozzle; and, a thermal insulator disposed along the axis of the nozzle separating the end point of the heating element and the temperature sensor.