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Grease Filter Cleaning and Replacement in London
Quick answer: Grease filters should be washed weekly, or daily in busy frying, wok and grill kitchens, and replaced when they are bent, damaged, corroded or no longer sit tightly in the canopy. A professional filter service deep-cleans the filters, checks the fit and housing, and replaces any that are past repair, usually as part of a full canopy and duct clean.
Duct Clean London cleans and replaces commercial kitchen grease filters for restaurants, takeaways, hotels and schools across North West, West and Central London. This guide explains when to clean, when to replace and what a professional service includes.
Why grease filters matter
Filters are the first barrier between the cooking line and the ductwork. A clean, well-fitted filter catches grease in the canopy, where it can be cleaned easily. A dirty, damaged or missing filter lets grease into the duct, where it builds up out of sight and becomes a fire risk. Good filter care is the cheapest way to slow down grease build-up between TR19 cleans.
Types of grease filter
| Type | How it works | Clean or replace? |
|---|---|---|
| Baffle filter (stainless steel) | Forces air to change direction so grease drops out | Wash and reuse. The standard choice for most UK commercial kitchens. |
| Mesh filter | Layers of metal mesh trap grease | Washable, but clogs quickly and is less effective. Many kitchens upgrade to baffles. |
| Cartridge or cyclone filter | High-efficiency separation built into the canopy | Clean to the manufacturer’s instructions. |
| Carbon filter (odour control) | Absorbs odour, not grease | Replace, do not wash. |
How often to clean grease filters
- Daily: heavy frying, chargrill, wok or high-volume kitchens
- 2–3 times a week: moderate use
- Weekly: light use, cafés and preparation kitchens
For a step-by-step method your team can use, see how to clean kitchen baffle grease filters.
When to replace a grease filter
- The frame is bent and leaves gaps when fitted
- The baffles are dented, split or corroded
- Grease has baked on and will not shift with soaking
- The filter is the wrong size for the housing
- Filters are missing, so the canopy has open gaps
Never run a canopy with filters missing. Fit a correctly sized replacement or a blanking plate.
What a professional filter service includes
- Remove every filter and note its position and condition
- Deep-clean in a hot soak or degreasing solution to remove baked-on deposits
- Clean the filter housing, channels and plenum behind the filters
- Check the fit, and replace damaged or ill-fitting filters with correctly sized ones
- Photograph before and after and record replacements in your report
We usually combine this with canopy cleaning, duct cleaning and extraction fan cleaning, because clean filters in front of a greasy duct do not reduce the fire risk.
Filters are not a TR19 clean
Washing filters is important, but it does not clean the plenum, ductwork, fan or discharge. TR19 Grease covers the whole extract route. Use our kitchen extraction cleaning checklist to split jobs between your team and a specialist.
Frequently asked questions
How often should commercial kitchen grease filters be cleaned?
Daily in heavy frying, grill or wok kitchens, two to three times a week in moderate kitchens, and at least weekly in light-use kitchens.
When should grease filters be replaced?
When they are bent, split, corroded, the wrong size, or no longer sit tightly in the canopy, or when baked-on grease cannot be removed.
Can carbon filters be washed?
No. Carbon filters control odour and are designed to be replaced, not washed.
Does cleaning grease filters count as TR19 cleaning?
No. TR19 Grease covers the canopy, plenum, ductwork, fan and discharge. Filters are only the first part of the system.
Do you supply replacement grease filters in London?
Yes. Duct Clean London can measure, supply and fit correctly sized replacement baffle filters as part of a canopy or extraction clean.
Book a measured clean in London
Duct Clean London cleans canopies, filters, ductwork and extract fans across North West, West and Central London (Zones 1–4), with grease readings and photographs in every report. Call 07843 141416 or send a booking enquiry with your postcode and a few photos of your system.
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