What you're doing when you remove a microwave and install a range hood

You're taking out an appliance that sits above your stove and vents upward or recirculates air, then putting in a different appliance that does the same job but works differently. A microwave oven heats food; a range hood removes steam, smoke, and cooking odors from your kitchen. If your microwave is mounted above the stove (called an over-the-range microwave), the space and the ductwork or electrical connections may already be partly ready for a range hood, but you'll still need to remove the old unit, patch or modify the wall, and install the new one.

This is a project you can do yourself if you're comfortable with basic tools and following electrical safety steps, or you can hire an appliance installer or electrician. The hardest part is usually disconnecting the old microwave safely and making sure the new hood vents properly—either to the outside or through a recirculating filter system.

Key Takeaways

  • Turn off power at the breaker before you touch any wiring on the old microwave to avoid electrical shock.
  • An over-the-range microwave and a range hood use the same mounting space, but you may need to patch drywall or modify ductwork depending on how the microwave was vented.
  • Range hoods need either a duct to the outside (preferred) or a recirculating filter system that cleans and returns air to the kitchen.
  • The mounting bracket, electrical outlet, and duct opening must all align with the new hood's specifications before you install it.
  • If you're unsure about electrical work or ductwork, hire a licensed electrician or HVAC technician rather than risk a fire or poor ventilation.

Turn off the power and disconnect the old microwave

Locate the circuit breaker that controls the microwave. It's usually labeled in the breaker panel in your basement, garage, or utility closet. Switch it to the OFF position. Test the microwave by pressing buttons to confirm it has no power. This step prevents electrocution when you touch the wiring.

Open the microwave door and look underneath or inside the cabinet above it for mounting bolts or screws. Remove them. Carefully pull the microwave toward you and slightly downward—it may be heavy, so have someone help. Once it's loose, you'll see the electrical cord plugged into an outlet or hardwired into a junction box. If it's plugged in, unplug it. If it's hardwired (connected with wire nuts or a terminal block), use a screwdriver to loosen the terminal connections and separate the wires. Take a photo of the wire connections before you disconnect them, in case you need to reference the colors later.

Once the microwave is free, set it aside. You now have an empty space above your stove.

Assess the existing ductwork and electrical setup

Look at the wall or cabinet behind where the microwave was. If there's a metal duct running upward, the microwave was vented to the outside (or to an attic, which is less ideal). If there's no duct and the space is open, the microwave was recirculating—pulling air through a filter and pushing it back into the kitchen. You'll need to know which one you have because it affects how you install the new hood.

Check whether the electrical outlet or hardwired connection is still accessible and functional. If the microwave was hardwired, you can either keep it hardwired for the new hood (if the hood accepts hardwiring) or install a standard outlet in that location. If an outlet is already there, the new hood may plug into it directly.

Measure the width of the space and the height from the stovetop to the bottom of the cabinet or wall. Range hoods come in standard widths (usually 24, 30, 36, or 42 inches). The hood you choose must fit the space and align with your stove's width. Most hoods should be 20 to 24 inches above the cooking surface.

Remove the old ductwork or patch the wall

If the microwave was vented outside, you'll see a duct running upward. You have two choices: keep the duct in place for the new hood, or remove it and patch the wall or cabinet.

To keep the duct, measure its diameter (usually 3.25 or 4 inches) and make sure the new hood's duct collar matches. If the diameters don't match, you'll need a reducer fitting or an adapter. If you're removing the duct, disconnect it from the microwave opening and from wherever it exits the house (usually the roof or a wall). Patch the hole in the wall or roof with caulk, flashing, or drywall, depending on the location. If the duct ran through a cabinet, you may need to patch the cabinet interior with wood or metal.

If the microwave was recirculating (no duct), the wall behind it is likely solid. You don't need to do anything unless the new hood requires a duct to the outside, in which case you'll need to cut a hole and run new ductwork—this is a job for an HVAC technician.

Install the mounting bracket and prepare the electrical connection

Most range hoods come with a mounting bracket that attaches to the wall studs or cabinet frame above the stove. Hold the bracket in place at the correct height (usually 20 to 24 inches above the cooking surface) and mark the screw holes with a pencil. Use a level to make sure the bracket is straight. Drill pilot holes and screw the bracket into the studs or cabinet frame using the fasteners provided. Do not use drywall anchors alone—the hood is heavy and needs to be anchored to solid wood.

If the new hood is hardwired, you'll need to run electrical wire from the breaker panel to a junction box near the hood's location. This requires turning off the main breaker and running new wire through the walls—a job for a licensed electrician. If the hood plugs in, make sure the outlet is positioned so the cord reaches without stretching, and that it's not in a location where it could get wet or damaged.

Connect the ductwork to the new hood

Slide the hood's duct collar (the metal fitting on the back or top of the hood) into the existing duct opening, or connect it to new ductwork if you're running a duct for the first time. Use metal duct tape or hose clamps to find the connection—do not use standard cloth duct tape, which can catch fire. Make sure the duct is as straight as possible and slopes slightly downward toward the outside to prevent condensation from running back into the hood.

If you're using a recirculating hood (one with a charcoal filter that returns air to the kitchen), you don't need ductwork. The hood straightforward sits on the bracket, and you install the filter inside according to the manufacturer's instructions.

find the hood and test the power

Lift the hood onto the mounting bracket and align the screw holes. Tighten the screws firmly but do not overtighten, which can crack the hood's housing. Install any trim ring or decorative frame that came with the hood to hide the gap between the hood and the wall or cabinet.

Turn the breaker back on. If the hood is hardwired, it should power on when ready. If it plugs in, plug it in now. Turn on the hood's fan and listen for unusual noises. Check that air is being pulled into the hood (hold a piece of paper near the vent opening—it should be drawn toward the hood). If the hood is vented outside, go outside and feel for air coming out of the duct opening. If you feel nothing, the duct may be blocked or disconnected.

When to call a professional

Call a licensed electrician if you need to run new electrical wire from the breaker panel, if you're unsure about the existing wiring, or if the hood requires hardwiring and you've never done it before. Electrical mistakes can cause fires or shock.

Call an HVAC technician if you need to cut a new duct opening through an exterior wall or roof, if you're running ductwork for the first time, or if the existing duct is damaged or blocked. Poor ductwork can cause the hood to work poorly or allow moisture and pests into your home.

Call an appliance installer if you want someone else to handle the entire job. Many appliance stores offer installation services for a fee, and some include it with purchase.

Frequently Asked Questions

Can I install a range hood if there's no existing duct?

Yes, but you have two options. You can install a recirculating hood with a charcoal filter, which requires no ductwork and plugs into an outlet. Or you can have an HVAC technician cut a hole through the wall or roof and run new ductwork to the outside. Venting to the outside is more effective at removing moisture and odors.

Do I need to hire someone to remove the microwave?

No, you can do it yourself if you turn off the power at the breaker first and take care not to drop it. The hardest part is usually disconnecting the wiring safely. If you're uncomfortable with electrical work, hire an electrician just for the disconnection and reconnection.

What size range hood do I need?

The hood should be at least as wide as your stove, and ideally 1 to 3 inches wider on each side. Standard widths are 24, 30, 36, and 42 inches. Check your stove's width and the space above it before you buy. The hood's height above the stove should be 20 to 24 inches for best performance.

Can I use the same electrical outlet for the range hood that the microwave used?

If the microwave was plugged into an outlet, yes—most range hoods can plug into a standard outlet. If the microwave was hardwired, you can either have an electrician install an outlet in that location, or have them hardwire the new hood the same way. Check the hood's manual to see which option it supports.

How often do I need to replace the filter in a recirculating range hood?

Charcoal filters in recirculating hoods typically last three to six months, depending on how much you cook. Check the filter monthly and replace it when it looks dark or clogged. Some hoods have washable metal filters that last longer—check your hood's manual for the specific type and replacement schedule.