Abstract: A heat exchange system for heating, ventilation, and air conditioning (HVAC) may comprise a burner box, a hot collector box, and a heat exchanger tube. The heat exchanger tube may be disposed between, and in fluid communication with, the hot collector box and the burner box. The heat exchanger tube may be rigidly connected to at least one of the hot collector box or burner box by a swaged joint.

Abstract: A heat exchanger tube includes a first pass for at least partially combusting a fuel and the first pass having a modified shape including a minor diameter and major diameter that reduces the external pressure drop of an external fluid flowing across the heat exchanger tube. A HVACR system includes a heat exchanger tube with a first heat exchange pass that at least partially combusts a fuel and has a modified shape. A method of making a heat exchanger including configuring a first heat exchange pass such that the major diameter of modified portion of the first heat exchange pass is oriented towards an incoming direction of the process fluid.

Abstract: A heat exchanger tube includes a first pass for at least partially combusting a fuel and the first pass having a modified shape including a minor diameter and major diameter that reduces the external pressure drop of an external fluid flowing across the heat exchanger tube. A HVACR system includes a heat exchanger tube with a first heat exchange pass that at least partially combusts a fuel and has a modified shape.

Abstract: A heating, ventilation, and/or air conditioning (HVAC) system may include a heat exchanger comprising at least one heat exchanger tube. The heat exchanger tube may include multiple passes: a first pass, a second pass having an elliptical portion with ribs disposed in the elliptical portion, a third pass having an elliptical portion with ribs disposed in the elliptical portion, and a fourth pass having an elliptical portion with ribs disposed in the elliptical portion. The first pass and the second pass may be connected in fluid communication by a first bend, the second pass and the third pass may be connected in fluid communication by a second bend, and the third pass and the fourth pass may be connected in fluid communication by a third bend. The heat exchanger tube may be configured to promote heat transfer while also controlling a pressure drop across the heat exchanger tube.

Abstract: A heat exchange system for heating, ventilation, and air conditioning (HVAC) may comprise a burner box, a hot collector box, and a heat exchanger tube. The heat exchanger tube may be disposed between, and in fluid communication with, the hot collector box and the burner box. The heat exchanger tube may be rigidly connected to at least one of the hot collector box or burner box by a swaged joint.