A temperature sensor for a radiant heater has a first tubular expansion element which is connected to its housing and contains a second rod-like expansion element, the two expansion elements having different coefficients of thermal expansion. The temperature sensor has two switching springs for different switching points. In order to adjust a second switching spring, which is fastened to a second switching spring base, the second switching spring base can be moved in the longitudinal direction of the rod and is then permanently fixed by bending or welding.