Quick Answer
Soak metal cooker hood or extractor fan filters in hot water with washing up liquid and a spoonful of baking soda for 10 to 15 minutes, then scrub gently with a soft brush and rinse thoroughly. They can also go in the dishwasher on a hot cycle. Clean grease filters every 2 to 4 weeks with heavy cooking use, and replace carbon filters, which cannot be washed, every 3 to 6 months.
Why This Matters Beyond a Tidy Kitchen
Grease is flammable, so a clogged, grease-laden filter is a genuine fire risk, not just a cosmetic issue. A blocked filter also reduces your extractor’s suction power, leaving more steam, smoke, and odour lingering in the kitchen, and the trapped grease and moisture create an ideal breeding ground for bacteria over time.
Two Types of Filter
| Filter Type | Washable? | Replace/Clean Frequency |
|---|---|---|
| Metal mesh or aluminium grease filter | Yes, washable and reusable | Clean every 2 to 4 weeks |
| Carbon/charcoal filter (recirculating hoods) | Usually not, though some can be recharged in an oven | Replace every 3 to 6 months |
Removing the Filters
Always check your specific model’s manual first, since release mechanisms vary, but most metal filters unclip or slide out after releasing a catch or turning a small knob. Turn off and allow the hood to cool fully before removing anything.
The Soak Method
- Fill a sink, large pan, or bucket with very hot or boiling water
- Add a generous squeeze of washing up liquid and a spoonful of baking soda
- Fully submerge the filters, or soak in batches if they do not fit
- Leave to soak for 10 to 15 minutes to loosen grease
- Scrub gently with a soft brush or sponge, taking care with the mesh so it is not bent or damaged
- Rinse thoroughly in clean hot water
- Dry naturally or pat dry with a soft cloth, never applying direct heat to speed drying
Cleaning Metal Filters in the Dishwasher
Metal mesh filters can go in the dishwasher on the hottest available cycle, at least 65°C, which helps break down grease effectively. Place them on the top rack and make sure they are the only item in that cycle, since built-up grease can transfer onto other dishes. Dry thoroughly with a cloth once the cycle finishes.
Dealing With Stubborn, Burnt-On Grease
For filters with heavy, caked-on residue, a dedicated degreaser added to the soak, or a longer soak of 20 to 30 minutes, usually shifts what a quick wash will not. Repeating the soak-and-scrub cycle once or twice on very neglected filters is generally more effective, and safer for the mesh, than scrubbing harder with a stiff brush.
Carbon Filters Need a Different Approach
Carbon or charcoal filters, found in recirculating (non-ducted) cooker hoods, trap odours and airborne particles rather than just grease, and cannot be washed the way metal filters can. Most need replacing once saturated, though some carbon filters are designed to be recharged by heating them in an oven, which releases trapped pollutants and restores their absorbency. Always check your specific filter’s packaging, since not all carbon filters support this.
Cleaning the Cooker Hood Casing
While the filters soak, wipe down the exterior casing with a soft cloth and warm water with a little washing up liquid. For a stainless steel hood, a dedicated stainless steel cleaner or a diluted vinegar solution lifts tougher marks without scratching the finish. Avoid abrasive scourers, which can dull or scratch the metal surface permanently.
Keeping Grease Buildup Under Control Between Cleans
- Wipe the filter surface with a cloth or paper towel after each cooking session, once cooled
- Always switch the extractor fan on when using the hob, particularly when frying
- Deal with grease splashes and stains on the hood casing as soon as they appear, rather than letting them build up
Frequently Asked Questions
How often should I clean my cooker hood filter?
Every 2 to 4 weeks for metal grease filters with regular cooking, though heavy daily use may need weekly attention.
Can I put cooker hood filters in the dishwasher?
Yes, metal mesh filters can go in a dishwasher on a hot cycle of at least 65°C, run separately from other dishes.
How do I know if my filter is carbon or metal?
Metal filters are typically a rigid mesh you can see light through and feel greasy to the touch, while carbon filters are usually a black, cushioned panel that should not be washed.
Can carbon filters be reused?
Some are designed to be recharged by heating in an oven, though most simply need replacing once saturated, so check your specific product’s guidance.
What happens if I never clean the filter?
Grease builds up to the point of becoming a fire risk, extraction performance drops significantly, and trapped grease and moisture can breed bacteria.