A double wall oven has two ovens stacked on top of each other that mount inside a cabinet. They are a great way to utilise space if you have limited room in your kitchen. If you need to remove the oven for maintenance or for replacement, you can basically follow the installation process in reverse. Removing the oven should take less time than installing it.
Open the cabinet door directly above the oven. You will locate an electrical junction box or electrical plug. You will also locate the vent stack coming out of the top or side of the oven.
Turn off the power to the oven at the breaker panel if you have a junction box. Open the cover on the junction box with a screwdriver and disconnect the wires. Place wire nuts on the wires coming out of the wall, and tape the wire nuts with electrical tape to prevent a short. If you have an electrical plug, do not turn off the power. Simply unplug the appliance.
Disconnect the vent stack. In most cases, you will locate bolts that secure the vent stack to the top of the oven. Use a socket set to remove the bolts, and then pull the stack from the oven.
Inspect the floor of the cabinet for mounting screws that hold the top of the oven in place. Remove the screws with a screwdriver. At this point, have an assistant hold the front of the oven to keep it from tilting forward.
Remove the oven doors from the oven. In most cases, tilt the doors out and lift up on them to remove them from their hinges.
Remove the screws that mount through the inner edge of the oven and go into the oven's mounting brackets.
Pull the oven out of the wall. This usually takes two people, due to the weight of the oven.