How to Hook Up Oven Exhaust Fans

Install the ductwork for the exhaust fan, if it is not already present. Measure the vent on top of the ventilation hood. Use this as a measurement for cutting holes in any intervening walls with a jigsaw.

Make a hole in the outside of the house or building for the exhaust fan vent cap. In most cases, this hole also needs to be the size of the ductwork. Use a reciprocating saw on wooden structures. On stone structures, use a stone cutting bit to drill holes in the perimeter of the hole. Knock out the center of the hole with a chisel. Sand or file down any rough edges with a file.

Apply weatherproof silicone caulk to the underside of the vent cap. Secure the vent to the outside wall of the structure with screws.

Attach one end of a flexible duct to the inside of the external vent. Secure it with a clamp. Run the other end to the exhaust fan location.

Mount the oven vent hood on the wall first by holding up the hood on the wall and marking holes for the screws. Drill holes in the wall on the marks with the appropriate drill bit for your wall surface and insert the anchors. Replace the hood and secure it with screws.

Connect the end of the duct to the top of the hood with a clamp.

Connect the other end of the ductwork to the top of the vent hood.

Turn off the electrical power to the oven and any other circuits, such as the kitchen lighting, where you may need to connect the exhaust fan wiring. Remove the cover of the electrical panel on the inside of the hood. Use a wire stripper to remove about half an inch from the end of a three wire (black, white, ground) cable. At the exhaust fan wiring panel, connect the black wire to the terminal marked "live," the white wire to the terminal marked "neutral" and the ground wire to the green grounding screw. Run the three wire electrical cable from the panel box to the nearest circuit junction. At the junction box, repeat the process of tying in the white and black wires into the wiring circuit and the green wire to the grounding screw.

Restore the power for the oven or electrical circuits. Turn on the exhaust fan and ensure that it works correctly.