The contribution of this research is to determine the change in the heat flow by the axial torsion in a tube of square cross section. The tube studied is part of a prototype heat exchanger designed and built by the research group in "Engineering and simulation of energy processes" of the Universidad Veracruzana, Coatzacoalcos region, Veracruz. The experimental prototype was designed and constructed with PVC pipe and the test section with aluminum tubes. The heat transfer of equipment was from 5 to 60 kJ with volumetric flows from 3 to 20 l/min and water as a working fluid. The tube without axial torsion (0°) is compared with three other tubes with 180°, 360° and 540° torsion. The experimental results reported in this study show the preliminary experimental tests where four levels of water flow are configured, using flow and temperature measurement instruments. The preliminary experimental results reveal an increase in the heat transfer in the equipment as the degree of axial torsion in the square section tubes is increased.