how do i clean the inside? the top has this brown splattered film that won't come off

Diagnosis

The brown splattered film on the ceiling of your Farberware FMO11AHTBKB is a result of "carbonized lipid buildup." When food splatters during the heating process, the fats and sugars are subjected to repeated microwave energy cycles. Because the top of the cavity is the furthest point from the turntable, it often remains unnoticed until the residue has been "baked" or caramelized into a hard, resin-like lacquer that bonds to the epoxy coating of the interior walls. This film is particularly stubborn because the FMO11AHTBKB uses a specific interior paint designed for heat resistance, and once organic matter carbonizes, it creates a chemical bond with that surface. If you try to scrub this off while dry, you risk scratching the interior coating, which can lead to "arcing" (electrical sparking) in the future. You can confirm this is carbonized grease if the spots are slightly raised and feel tacky or rock-hard to the touch, rather than just being a surface stain.

How to Fix It

To remove this without damaging the interior finish, you must use a controlled steaming process to rehydrate the carbonized proteins.

1. Fill a microwave-safe glass bowl (at least 2 quarts) with 3 cups of distilled water and 3 tablespoons of white distilled vinegar. Adding a slice of lemon can help break down alkaline grease deposits.
2. Place the bowl in the center of the turntable. Ensure the bowl is not touching the side walls.
3. Set the microwave to High power and enter 8 minutes. Start the cycle.
4. Once the timer hits zero, do not open the door immediately. Let the unit sit undisturbed for 10 to 15 minutes. This allows the steam to penetrate the porous layers of the brown film on the ceiling.
5. Open the door and carefully remove the bowl (it will be extremely hot).
6. Using a clean, damp microfiber cloth or a soft sponge, wipe the ceiling first. Use a circular motion, applying moderate pressure. The film should now slide off as a softened sludge.
7. Wipe the side walls and the floor of the cavity, finishing with the turntable area.
8. Dry the interior completely with a lint-free towel to prevent spotting.

If That Didn't Work

• Baking Soda Paste Method: For "islands" of brown residue that remain, mix 2 parts baking soda with 1 part water to create a thick, toothpaste-like consistency. Apply the paste directly to the brown spots on the ceiling. Let it sit for 30 minutes to chemically break the bond, then gently scrub with a soft toothbrush before wiping clean with a damp cloth.
• Isopropyl Alcohol Solution: If the residue is oil-based and resists steam, dampen a cotton ball with 70% isopropyl alcohol. Gently dab the spot—do not scrub aggressively. The alcohol acts as a solvent for the lipids. Immediately wipe the area with water to remove any chemical residue before operating the microwave.
• Commercial Degreaser Application: Apply a small amount of a citrus-based degreaser to a sponge. Apply it only to the affected area on the ceiling. Let it dwell for 5 minutes, then wipe clean. Ensure you rinse the area three times with a wet cloth to ensure no soapy residue remains, as soap can cause pitting in the interior coating when heated.

Heads Up

• Avoid Abrasives: Never use steel wool, scouring pads, or bleach on the interior of the FMO11AHTBKB. These will strip the protective epoxy coating, leading to permanent rust or dangerous electrical arcing.
• Cover Your Food: The best way to prevent this film is to use a microwave-safe plastic or glass splatter cover on every dish. This keeps the grease from reaching the ceiling.
• The 30-Second Rule: If you notice a splatter immediately after cooking, wipe it out while the oven is still warm. Once the unit cools, the grease hardens, making it ten times harder to remove.
• Ventilation Check: Ensure the microwave is not pushed too tightly against a wall; proper airflow prevents the exterior and interior from overheating, which can accelerate the "baking" of food residues.