How do I repair steam flat irons

Yes, when the iron gets too hot the thermal fuse will blow to protect the heating element. They can be replaced with the same value. No soldering here, only use appropiate wireclamps for high temperature purposes. Thermal fuses can fail due to a failing thermostat (the rotary knob you set the temerature with), so you probably have to solve the cause of the problem as well.

Measure the thermal fuse with a multimeter, they should measure 0 ohms. Open means defective. Thermal fuses are usually mounted near the heating element. If thermal paste is used, make sure there’s enough left when you mount a new one for optimal thermal protection.