How to Clean a Microwave Exhaust Blower Fan

Where the exhaust blower fan lives

An exhaust blower fan is the part of a vented microwave that pulls cooking air through the vent openings. On an over-the-range microwave, the fan sits behind the vent grille and is often the same fan that draws smoke, steam, and airborne grease away from the cooktop. Over time the fan blades collect a thin grease film, and dust in the kitchen sticks to that film.

The fan is normally a round wheel with angled blades mounted inside a housing. On over-the-range models, the grille may be on the upper front of the body or on the lower front edge, depending on the design. Built-in microwaves can vent from the top, rear, or front, so the blower location varies. If you are not sure where the fan is, the blower location reference explains the common arrangements.

Before removing anything, identify the vent type. A ducted setup pushes air outside through ductwork. A recirculating setup pulls air through a filter and releases it back into the kitchen. The blower cleaning steps are similar either way, but a recirculating model may have a charcoal filter in the air path that needs separate attention. See venting types and over-the-range filters.

Countertop microwaves usually do not have an exhaust blower; they rely on cooling vents around the cabinet. If your model has no vent fan, focus on the intake vents instead: air intake vents.

What you need

Gather everything before you start. You want supplies that remove grease without leaving moisture pooled near electrical parts. A simple kit covers most vent fans.

Step-by-step cleaning

Unplug the microwave before touching any vent part. Work slowly, and stop if a screw will not turn or a clip will not release. Forcing the grille can damage the mounting points.

• Unplug the microwave and wait a moment before removing anything.
• Locate the vent grille. On many over-the-range models it is on the upper front or lower front edge.
• Remove the screws or release the clips that hold the grille. Set the grille aside on a soft surface.
• Look for a grease filter or charcoal filter in the air path. Follow the owner's manual if either filter needs cleaning or replacement before you can reach the fan.
• Use the vacuum brush to draw loose dust away from the area. Do not let the nozzle touch wiring.
• Loosen caked dust with the soft brush, then vacuum again.
• Dampen a microfiber cloth with warm water and a little mild degreaser. Wipe each fan blade from the hub outward, then wipe the housing.
• Wipe the back of the grille as well. For a deeper grille job, see cleaning the vent grille.
• Let every part dry completely before reassembly.
• Replace the grille, restore power, and run the vent fan briefly to confirm airflow.

What not to do

Cleaning a blower fan is a gentle job. The fan wheel is balanced, the motor is not meant to get wet, and the area behind the grille is close to electrical parts. Keep liquids and tools in check.

• Do not spray cleaner directly into the vent opening or onto the motor.
• Do not use abrasive pads, scrapers, or metal brushes on the fan blades.
• Do not force the fan to spin by hand. A bent blade can cause vibration or noise.
• Do not run the microwave with the grille removed.
• Do not open the chassis beyond the grille. The high-voltage section is not part of routine cleaning; see microwave high-voltage parts safety.

How often and when to call for service

Frequency depends on how much grease your cooking puts into the air. If you sear, fry, or broil under the microwave, check the fan more often. If you mostly reheat food, the blower can go longer between cleanings. Let visible grease on the grille or a drop in airflow be your cue. Cleaning the blower is part of a broader microwave maintenance schedule.

If the grille screws are stripped, the filter is damaged, the fan will not turn, or the motor sounds rough, stop and contact the manufacturer's support service or a qualified technician. Appliance makers publish manuals and service options through their owner support pages. GE Appliances, for example, offers appliance manuals and service scheduling on its site.

Once the microwave is back in service, follow normal food safety practices when reheating. The FDA's microwave guidance says to cover food, stir, and rotate for even cooking, and to allow standing time before checking temperature.

If an older microwave can no longer be serviced, do not assume it belongs in the trash. The EPA notes that electronics contain valuable materials and can be recycled; check community electronics recycling options before disposal.

What to pick for your use

Questions

Does every microwave have an exhaust blower fan?

No. This guide applies to over-the-range microwaves and some built-in models with a vent fan. Countertop microwaves generally do not have an exhaust blower; they have cooling vents that can be cleaned separately. Check the owner's manual or look for a vent grille with fan controls.

Can I clean the blower fan without removing the grille?

You can vacuum visible dust through the grille, but a thorough cleaning is much easier with the grille removed. Unplug the microwave first and follow the manual if the grille does not come off readily.

What should I use to cut through grease on the fan blades?

Warm water and a mild dish soap or degreaser on a microfiber cloth handle most kitchen grease. Wipe the blades from the hub outward, then follow with a clean damp cloth. Avoid abrasive pads and any liquid that could run into the motor.

How do I know the blower fan needs cleaning?

Visible grease on the vent grille, reduced airflow from the vent, or a noisier blower are common signs. When you notice buildup, clean the fan and inspect the surrounding filters.

When should I call for service instead of cleaning it myself?

Stop if the grille will not come off, the fan will not turn, you see damaged wiring, or the microwave makes unusual noises after cleaning. Contact the manufacturer or a qualified technician. Do not open the high-voltage chassis.