Abstract: A header box for a heat exchanger assembly and the method of manufacture. The header box has a first header component and a second header component. The first header component has a first corner portion with a first wall and a second wall extending therefrom. The second header component has a second corner portion with a third wall and a fourth wall extending therefrom. Free ends of the first wall and the third wall cooperate to form a first seam which is welded to maintain the first wall in position relative to the second wall. The free ends of the second wall and the fourth wall cooperate to form a second seam which is welded to maintain the third wall in position relative to the fourth wall. The header box, with the first corner portion and the second corner portion, will withstand the stress concentrations associated with a flow of fluid in the header box.

Abstract: A sonde comprising a first sensor and a second sensor adjacent the first sensor, the first sensor including an optical window and a wiper element, the wiper element rotating on a shaft extending from the first sensor so as to clean debris from the window, a brush extending from the wiper element beyond the perimeter of the first sensor such that the brush contacts the adjacent second sensor and removes debris which accumulates on the second sensor.

Abstract: A sonde comprising a first sensor and a second sensor adjacent the first sensor, the first sensor including an optical window and a wiper element, the wiper element rotating on a shaft extending from the first sensor so as to clean debris from the window, a brush extending from the wiper element beyond the perimeter of the first sensor such that the brush contacts the adjacent second sensor and removes debris which accumulates on the second sensor.