--- title: "Cleaning the grease filters and changing the charcoal filter" description: "The mesh filters under a microwave hood combination, the charcoal pad behind its top grille, how often each needs attention and the cleaner that darkens the…" url: "https://microwaverepair.center/guides/cleaning-the-grease-and-charcoal-filters/" date_modified: "2026-09-26" --- Maintenance and prevention # Cleaning the grease filters and changing the charcoal filter A microwave grease filter is the metal mesh under a hood combination that traps grease from the pans below. GE Appliances advises cleaning it about once a month by soaking it in hot water and detergent, without ammonia. A charcoal filter, used only when the air is recirculated, cannot be cleaned and is replaced when dirty, usually every 6 to 12 months. By [MicrowaveRepair.center technical team](https://microwaverepair.center/authors/technical-team/) Published September 26, 2026 ## At a glance. Only the microwave hood combination has these filters, and they are the one part of it that asks for a monthly chore. The metal mesh underneath is washed and reused; the charcoal pad behind the top grille, if there is one, is thrown away and replaced. Read the whole guide ### Metal grease filters About once a month, or sooner Hot water and detergent; no ammonia, which darkens the metal. ### Charcoal filter Replaced, never washed Usually after 6 to 12 months, depending on use. ### Who has a charcoal filter Recirculating installations only A unit ducted outside does not use one. ### Built-in, drawer and countertop models No filters They have no fan for the cooking surface. In this guide 1. Two filters with two different jobs 2. How often each one needs attention 3. Washing the metal mesh without darkening it 4. Fitting a new charcoal filter 5. Step by step 6. Questions ## Two filters with two different jobs Under the front edge of a hood combination sit one or two flat metal mesh panels, each of them a microwave grease filter. They catch the grease carried up in steam and smoke from the pans below, and a GE Appliances owner's manual adds a second reason for them: they keep flames from the cooking surface from reaching the inside of the unit, which is why they must always be in place when the fan runs. The charcoal filter is a different part. It is a pad of activated carbon behind the grille across the top front of the microwave, and it exists only when the air is blown back into the kitchen rather than out of the house. GE states plainly that it cannot be cleaned and must be replaced. ### Ducted to the outside If the unit sends air up a duct through the cabinet or out through the back wall, there is no charcoal filter to change. The metal grease filters still need their monthly wash, since grease reaches the duct if they are clogged or missing. ### Recirculating into the room If the air comes back out of the grille above the door, the unit is recirculating. It then carries both kinds of filter, and it is the charcoal pad that does the work on odors. Source: [GE Appliances — Over the Range Microwave Oven Owner's Manual (LVM1335)](https://www.geappliances.com/content/older-pdfs/79-40007.PDF) — Grease filters must always be in place and are cleaned once a month or as needed by soaking in hot water and detergent without ammonia; the charcoal filter cannot be cleaned and is replaced when dirty, usually after 6 to 12 months; disconnect power before removing the grille ## How often each one needs attention The GE manual for one of its over-the-range models asks for the grease filters to be cleaned once a month, or as needed, and for the charcoal filter to be replaced when it is noticeably dirty or discolored, usually after 6 to 12 months depending on how much the fan is used. A household that fries often will land at the short end of both. GE's support pages add practical signs that the charcoal pad is spent. A fresh pad looks dull and porous; one that looks shiny all over is loaded with grease. An old smell coming out of the grille, different from whatever is in the pans, means the pad has stopped trapping and started giving back. - Grease filter due: a tacky film on the mesh, drips forming at its edge, or a month since the last wash. - Charcoal filter due: a shiny surface, stale odors from the grille, or the 6- to 12-month mark passed. - Write the date on a strip of tape inside the cabinet above, so the next change is not a guess. Source: [GE Appliances — Over the Range Microwave Oven Owner's Manual (LVM1335)](https://www.geappliances.com/content/older-pdfs/79-40007.PDF) — Grease filters must always be in place and are cleaned once a month or as needed by soaking in hot water and detergent without ammonia; the charcoal filter cannot be cleaned and is replaced when dirty, usually after 6 to 12 months; disconnect power before removing the grille; [GE Appliances — Over-the-Range Microwave charcoal filter replacement](https://products.geappliances.com/appliance/gea-support-search-content?contentId=17457) — Charcoal filters are model specific; a shiny surface or odors unlike the food being cooked mean replacement; the filter sits loosely, is held by the running fan and may not cover the whole opening Close on a hand sliding a charcoal filter into the top vent of a microwave hood combination. ## Washing the metal mesh without darkening it Slide each filter toward the back by its tab, tip it down and lift it out. GE's instruction is to soak it and then swish it around in hot water with detergent, using light brushing for grease that has worked into the mesh. Ammonia and cleaners that contain it are to be avoided because they darken the metal. Rinse the filter, shake the water out and let it dry fully before it goes back, so water is not blown into the fan housing on the next use. While the filters are out, wipe the underside of the unit around the openings, where grease settles and the work light sits. ### When a filter is bent or torn A filter with a split in its mesh or a frame that no longer seats flat lets grease straight past it. Replace it with the part listed for the model rather than running without one; the manual treats the filters as required, not optional. Source: [GE Appliances — Over the Range Microwave Oven Owner's Manual (LVM1335)](https://www.geappliances.com/content/older-pdfs/79-40007.PDF) — Grease filters must always be in place and are cleaned once a month or as needed by soaking in hot water and detergent without ammonia; the charcoal filter cannot be cleaned and is replaced when dirty, usually after 6 to 12 months; disconnect power before removing the grille ## Fitting a new charcoal filter Charcoal filters are model specific, and GE lists the right part number in the owner's manual and the product specifications. Buy by that number rather than by the look of the old pad, since similar pads differ by a fraction of an inch. Many designs hide the pad behind a grille held by screws. The same GE manual asks owners to disconnect power at the breaker or pull the plug before taking the grille off. The new pad often sits loosely at an angle and may look smaller than its compartment; GE notes that the fan holds it in place once it runs and that a pad not covering the whole opening is normal. Have everything ready before the grille comes off, so the fan and light are without power for as short a time as possible and no screw ends up lost on the cooking surface below. - The replacement pad, bought by the part number in the manual. - A screwdriver that fits the grille screws, if your design uses them. - A small tray or cup to hold the screws. - A strip of tape and a pen to note the date of the change. Source: [GE Appliances — Over the Range Microwave Oven Owner's Manual (LVM1335)](https://www.geappliances.com/content/older-pdfs/79-40007.PDF) — Grease filters must always be in place and are cleaned once a month or as needed by soaking in hot water and detergent without ammonia; the charcoal filter cannot be cleaned and is replaced when dirty, usually after 6 to 12 months; disconnect power before removing the grille; [GE Appliances — Over-the-Range Microwave charcoal filter replacement](https://products.geappliances.com/appliance/gea-support-search-content?contentId=17457) — Charcoal filters are model specific; a shiny surface or odors unlike the food being cooked mean replacement; the filter sits loosely, is held by the running fan and may not cover the whole opening ## Where to stop Filters and the grille are the owner's side. A fan that stays silent, hums without turning or smells hot, a light socket that sparks, or any wish to look past the grille into the fan housing is for a technician: that housing sits beside the high-voltage section, and the capacitor there stays charged, and dangerous, after the power is off. Written by [MicrowaveRepair.center technical team](https://microwaverepair.center/authors/technical-team/). Technicians who repair home microwaves, writing from what each service call showed and from the makers' own manuals. Sources: [GE Appliances — Over the Range Microwave Oven Owner's Manual (LVM1335)](https://www.geappliances.com/content/older-pdfs/79-40007.PDF) · [GE Appliances — Over-the-Range Microwave charcoal filter replacement](https://products.geappliances.com/appliance/gea-support-search-content?contentId=17457) ## Step by step. Four steps, in the order worth doing them. 01 ### Turn off the fan and light Let the unit cool after cooking, and cut power at the breaker before removing any screwed grille. 02 ### Soak the grease filters Soak the mesh in hot water with detergent, swish it, brush lightly, and skip ammonia products. 03 ### Rinse and dry Rinse, shake out the water and let each filter dry fully before sliding it back into its frame. 04 ### Check or change the charcoal pad On a recirculating unit, replace a shiny or smelly pad with the part number from the manual, then restore power. For the heart of your home. ## Questions owners ask. ### Can the metal filters go through a dish cycle? Check the owner's manual for your model first. The GE manual quoted here describes hand washing in hot water and detergent, and warns against ammonia. ### Is it safe to run the fan without the grease filters? No. The filters are what stops grease and flames from the pans below reaching the inside of the unit, so they belong in place whenever the fan runs. ### How do I know whether my unit recirculates? Turn the fan on high and feel the grille above the door. Air blowing out there means it recirculates and needs a charcoal filter; no air there usually means it is ducted. ### Will a new charcoal filter fix a weak fan? It removes one cause of weak airflow. If the fan still sounds labored with clean filters, the motor or its speed control needs a diagnosis. ## The problems behind it. Each has a page of its own: what it usually means and the causes in the order worth checking. [All 17 problems](https://microwaverepair.center/problems/) Problem ### Microwave Vent Fan Not Pulling Steam 6 causes, cheapest first Problem ### Microwave Light Out Inside or Underneath 6 causes, cheapest first Stop using it ### Burning Smell From a Microwave 6 causes, cheapest first ## When it needs a technician. The repairs on the right are where this guide ends when the checks do not settle it. ### Microwave vent fan and filter repair Bringing back the exhaust fan of a microwave hood combination, from grease filters closed with residue and a spent charcoal filter to a blower motor, a speed relay or the heat switch that starts it. ### Microwave light and fuse repair Restoring a dark cavity lamp, a dead cooktop light under a hood combination or a microwave that went dead with a blown fuse, after finding what blew it. ## More in maintenance and prevention. The small routines that keep a microwave off our schedule, from soaking the grease filters and changing the charcoal one to wiping splatter off the waveguide cover and treating the door gently. [The whole section](https://microwaverepair.center/guides/maintenance-and-prevention/) Habits that keep it heating for years ### Keeping the cavity and the waveguide cover clean What the small panel on the cavity wall protects, why a spatter left on it can smoke or spark, how to clean around the turntable shaft and when the cover has to be replaced. Habits that keep it heating for years ### A yearly microwave check: door, heating, fan and mounting Twenty minutes once a year: how the door closes, a heating baseline in a mug, the fan and light, the mounting bolts or drawer guides, the cord, and a recall lookup by model number. Guides ### All 18 guides Six sections, by what you are trying to find out. --- **[Read on the site: Cleaning the grease filters and changing the charcoal filter](https://microwaverepair.center/guides/cleaning-the-grease-and-charcoal-filters/)** **[Book a visit with MicrowaveRepair.center](https://microwaverepair.center/schedule/)**