An electrical cartridge type heater (100) includes an outer metallic jacket (110) an electrical heating element (120, 121) arranged in an interior space (140) of the outer metallic jacket (110) and a device for monitoring the temperature (130), which is galvanically separated from the electrical heating element (120, 121) and is arranged in the interior space (140) of the outer metallic jacket (110). The device for monitoring the temperature (130) includes a wire or a tube, in addition to the electrical heating element (120, 121), made of a material that changes resistance with temperature change with a value of the temperature coefficient of the electrical resistance greater than 800 ppm/K, and especially preferably greater than 4,000 ppm/K between 20° C. and 105° C. The wire or the tube is directly embedded into an electrically non-conducting filler filling a remaining interior space (140) of the outer metallic jacket (110).