Based on the observation of the effects of energy generation on climate change, efforts have been carried out to develop technologies to reduce polluting energy sources. In this context, the rational use and improvement of the efficiency of water heating systems can play an important role, contributing to lower energy consumption. This study evaluated a prototype for water heating for use in agroindustry. The prototype was designed for a possible utilization of mechanical energy in order to change the magnetic flux produced by permanent magnets, generating thermal energy by Foucault currents. This system presented yields of 64.74%, 65.13% and 64.48% for the rotor configurations with six magnets without pole reversal (6ISI), four magnets with reversal (4ICI), and four magnets without reversal (4ISI), respectively. For comparison purposes, a resistive water heating system was also evaluated for the same study conditions, obtaining an efficiency of 89.21%. The proposed inductive system did not present satisfactory results for constructive conditions presented in the study.