Incorporates at least one thermal switch (5) in series with the heating resistor (4) of the module located on the frame (1) of said resistors (4) that cuts off current to the resistor (4) when the heater power control circuit fails. The thermal switch (5) can be between the heating resistor (4) and the earth connection of the support (6), or between the heating resistor (4) and the power supply (3) of the module. The module allows a closed-loop control using as variable the temperature of one of the resistors (4), whose resistivity can change with the temperature. Similarly, the electronic control circuit can also be integrated in the heater frame (1), allowing a closed-loop control of the dissipated power using as control variable the temperature of the frame (1).