How to Clean a Greasy Kitchen Exhaust Fan

Your Kitchen Exhaust Fan Is a Fire Hazard

If you cook regularly in your Jacksonville home, your kitchen exhaust fan has been silently accumulating grease with every meal. The National Fire Protection Association reports that cooking equipment is the leading cause of home fires, and greasy exhaust hoods are a significant contributor.

A buildup of just 1/8 inch of grease in the exhaust system creates a serious fire risk. In Jacksonville's heat, where we cook with the AC running and windows closed, the grease has nowhere to go but into the hood and ductwork.

Cleaning your exhaust fan isn't just about appearance — it's about safety and air quality. Here's how to do it thoroughly and correctly.

What You'll Need

• Degreaser (Simple Green, Krud Kutter, or a commercial kitchen degreaser)
• Hot water
• Bucket
• Stiff-bristle brush
• Old toothbrush
• Microfiber cloths
• Screwdriver (for removing the filter and cover)
• Trash bag
• Rubber gloves

Step 1: Remove and Clean the Filter

The filter is the most contaminated part of the exhaust system:

Metal Mesh Filters

• Remove the filter by sliding or unclipping it from the hood
• Fill a large pot or your sink with boiling water and 1/4 cup baking soda
• Submerge the filter and let it soak for 15-30 minutes
• Scrub with a stiff brush to remove loosened grease
• For stubborn grease, make a paste of baking soda and dish soap, apply, let sit 15 minutes, scrub
• Rinse thoroughly with hot water and dry before reinstalling

Charcoal Filters

• Charcoal filters cannot be cleaned — they must be replaced
• Replace every 3-6 months if you cook regularly
• These are common in ductless range hoods found in many Jacksonville apartments

Step 2: Clean the Hood Interior

Once the filter is removed, you can access the hood interior:

• Spray degreaser generously inside the hood housing
• Let it sit for 10-15 minutes to break down the grease
• Scrub with a brush — an old toothbrush works well for tight spaces around the fan motor
• Wipe clean with a damp cloth, rinsing frequently
• Pay special attention to the area around the light fixture — grease builds up there and creates a fire risk

Step 3: Clean the Fan Blades

The fan blades are often the most neglected part of the exhaust system:

• If you can access the fan blades, spray with degreaser and let sit 10 minutes
• Wipe each blade carefully with a cloth — greasy fan blades reduce airflow by up to 50%
• Be careful not to bend the blades or disturb the motor wiring
• If you can't easily access the blades, consider having a professional clean the system

Step 4: Clean the Hood Exterior

The visible part of the hood needs attention too:

• Spray degreaser on a cloth (not directly on the hood) and wipe all exterior surfaces
• For stainless steel hoods, wipe in the direction of the grain
• Use an old toothbrush to clean along the bottom edge where grease drips accumulate
• Polish with a dry microfiber cloth
• For copper or brass hoods (common in St. Augustine historic homes), use a metal-appropriate cleaner

Step 5: Clean the Ductwork (If Accessible)

If your hood vents outside, the duct between the hood and the exterior cap collects grease:

• Remove the exterior vent cap and clean it — insects and birds often nest in these
• If you can reach into the duct, wipe with a degreaser-soaked cloth on an extension pole
• For longer duct runs, professional duct cleaning may be necessary
• This is especially important in Jacksonville where humidity can cause grease inside ducts to become rancid

Maintenance Schedule

• Weekly: Wipe the hood exterior after heavy cooking
• Monthly: Remove and clean the filter
• Quarterly: Deep clean the entire hood system including the interior and fan
• Annually: Inspect and clean accessible ductwork

Preventing Grease Buildup

• Always turn the exhaust fan on BEFORE you start cooking — not after
• Leave it running for 10-15 minutes after you finish cooking
• Use the highest fan speed when cooking greasy foods
• Clean splatters and drips from the hood immediately — fresh grease wipes off easily
• Consider upgrading to a higher-CFM fan if yours doesn't seem to keep up

Professional Exhaust Fan Cleaning

At Clean Fix Jax, our kitchen deep cleaning service includes exhaust fan and hood degreasing. We remove and clean filters, scrub the hood interior and exterior, and clean accessible ductwork.

Kitchen deep cleaning starts at $100. We serve Jacksonville and surrounding areas. Contact us for a free estimate or check our FAQ for more about our services.