How to replace the thermal switch in a wall oven

Shut off the house circuit breakers for the wall oven to completely disconnect electrical power.

Set a sturdy work table or platform just in front of the oven and pad the surface of the table with a towel or cardboard to protect the table. 

Open the oven door and remove the mounting screws that secure the oven to the sides of the oven cabinet. Slide the oven forward in the cabinet. You should have enough slack in the electrical conduit of the power supply; if not disconnect the power supply wiring from the junction box for the wall oven.

With someone's help, carefully lift the oven out of the cabinet and set it on the table in front of the cabinet. 

Starting with the bottom screws, remove the mounting screws that secure the outer back panel to the oven frame. Press on the outer panel as you remove the last of the top screws to prevent the outer panel from falling.

Remove the outer back panel and set it aside.

Disconnect the wires from the thermal switch.

Remove the mounting screws from the thermal switch. Remove the existing thermal switch and set it aside for disposal. 

Position the new thermal switch on the back of the oven and line up the mounting screw holes. Insert the mounting screws and tighten them firmly.

Position the wires on the ends of the thermal switch terminals and push them onto the terminals. Push the female spade connectors all of the way down so that they seat properly.

Position the outer back panel on the oven so that the mounting screw holes line up. Starting at the top of the panel, insert the mounting screws and tighten them firmly.

With someone's help, lift the oven into the cabinet. Reinstall the mounting screws on the sides of the oven cabinet that hold the oven in place.

Reset the house circuit breakers for the oven to restore electrical power.