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During this cleaning process you will be working close to the electrical components of your exhaust fan. To minimize the risk of injury, fully unplug the exhaust unit before proceeding. In the event of faulty wiring or a broken switch, simply turning the fan off does not cut out electricity from every part of the appliance. Grease filters are rectangular, and made of metal mesh. They are located on the underside of the hood or microwave exhaust fan. If you have trouble finding your grease filter, consult the owner’s manual, or visit the manufacture’s website and find information for your specific make and model. Modern microwave systems sometimes have a small charcoal filter on top of the unit which filters out odors. This filter should be replaced every 6-12 months, depending on use. Unhook any levers or tabs that are holding the filter in place and gently pull the dirty filter out. Most filters will come out with little effort, but heavy grease build up may cause some filters to stick. Sliding a butter knife around the edge of the filter is an easy way to loosen up a stubborn filter. This will be the pan you are soaking and cleaning the filter in. The pan should be deep enough to fully submerge the filter in the cleaning solution. The average sheet pan is perfect for most grease filters.

Summary:
Turn off and unplug the exhaust fan. Locate the grease filter. Remove the grease filter. Place the grease filter in a pan or container.