Dispositivo riscaldante istantaneo per solidi, liquidi, gas e vapori

A heating device, comprising: a heater (2) made of a material the electrical resistance of which is variable according to a temperature; a power source (1, 10) connected to the heater (2) by means of electrical connections (8, 9) for sending an electric current which flows through the heater (2); a control module (4) that is arranged for adjusting the current supplied by the power source (1); measuring connections (6, 7) placed at the ends of the heater (2) and connected to the control module (4), which control module (4) is predisposed for measuring the resistance of the heater (2) by calculating a ratio between the voltage present at the ends of the heater (2) and the current crossing the heater (2), which are detected by way of the measuring connections (6, 7).