Brazed heat exchanger and method of making the same

Poor brazed joints in a heat exchange caused by improper venting during the brazing process are eliminated through the use of a baffle for disposition in a slot 32 in a tubular header 10, 12 which is formed of a plate-like metal piece having first and second peripheral sections 36, 40 of approximately the same extent. The first section 36 has a size at least as large as the outer dimension of the tubular header 10, 12 while the second section 40 has a size and shape approximately equal to a corresponding interior section of the tubular header 10, 12 and a notch 46 is disposed in the first section 36 and extends inwardly a distance 2t greater than the wall thickness t of the tubular header. The notch 46 provides a vent path during the brazing process which is subsequently filled by the capillary flow of molten braze metal 52 into the bottom 50 of the notch.