Abstract: A portable space heater features a tubular heat shield of generally uniform cross sectional configuration about and in longitudinally offset, concentric, closely spaced relation to a tubular shell defining its combustion chamber to project beyond a nose cone at its outlet end. The projection of the shield beyond the cone is limited to produce, upon a high velocity pressurized flow of air around the inner surface of and the length of the shield, distinctive flow of air within the projected end of the shield and about the nose cone the pattern of which produces an effective heat exchange with the products of combustion at the cone which substantially moderates the cone temperature.