Start with the filters you actually have
Most commercial kitchens run one of three filter types. Baffle (cage) filters, the metal zig-zag panels common under commercial hoods, are the workhorse: they trap grease by changing the direction of the air, and the grease drops into a trough. Mesh or charcoal filters, often fitted to recirculating hoods, collect grease in a fine wire mat and usually cannot be cleaned properly; they are replaced. Disposable mats, common in smaller cafés and coffee bars, are swapped out on a short cycle.
This matters for the routine, because baffle filters can be washed and reused, mesh filters generally must be replaced on schedule, and disposable mats simply get swapped. If you do not know which type you have, check the hood documentation or the filter frame itself before you plan anything else. A replacement interval written for mesh filters will not fit a baffle setup, and vice versa.
Set the interval from your cooking, not from a calendar default
Grease load is a function of what you fry, how much of it, and how many hours the hood runs. A wok line or a deep-fry station puts far more oil into the airstream than a salad or sandwich prep line, so the same hood in two different kitchens can need attention at very different rates.
Use this as a starting point and then adjust from what you see:
- Heavy frying, wok or char-grill work: check weekly, clean every one to two weeks.
- Mixed hot line with moderate frying: check weekly, clean every two to four weeks.
- Baking, griddling or low-fry cooking: check every two weeks, clean monthly.
- Recirculating hoods with mesh or charcoal filters: replace filters on the manufacturer's interval, typically monthly under regular use.
Do a simple touch test during each check. Run a finger across one baffle panel. A thin, oily film that wipes off means you are still within range. A tacky, sticky layer that resists the finger means grease has started to polymerise, and at that point cleaning takes real work rather than a quick soak. Catching filters at the film stage is the whole reason for a fixed check interval.
The cleaning cycle, step by step
For baffle filters, a repeatable cycle looks like this:
- Pull the hood and turn the extraction off at the switch, not just at the controls.
- Take the filters out one at a time, noting which slot each one came from so they go back the same way.
- Wipe the loose grease off each panel into a waste bin, not into the sink drain.
- Wash with hot water and a degreasing detergent. Hot water does most of the work here; cold water just moves grease around.
- For panels where the grease has hardened, soak them first, then re-wash and scrub the edges and the folds where buildup hides.
- Rinse, drain, and let the panels dry before refitting.
- While the filters are out, wipe the inside face of the hood lip, the grease trough and the filter rails. Those are the spots most people skip.
- Refit the filters in their original orientation and turn the extraction back on.
The grease trough and the drip points are worth naming separately because they are the part of the system that fails first when ignored. A clean filter above a full trough still leaks, and the overflow shows up as grease on the cooking line and, eventually, on the floor below the hood.
Where hot steam changes the job
Soaking and scrubbing works on light buildup, but on a busy frying line the grease hardens faster than the soak can soften it, and the panels spend a long time in a sink of detergent. Hot steam handles the hardened layer differently. Superheated vapour softens polymerised grease on contact, so the panels release the buildup without an overnight soak, and the same tool covers the hood interior, the trough, the rails and the panel faces in one pass.
That is the reason kitchens with a heavy hot line move to a commercial kitchen steam cleaning machine for this part of the routine. The fixed Fixed Steam Cleaning Machine PowerDe HW02 runs on a standard 220 V supply, delivers steam at 160 °C and 0.8 MPa with a 6 kW heater and an 80-litre stainless tank, and switches between dry and wet steam. Dry steam is the right mode for cutting hardened grease on filter panels and hood surfaces; wet steam covers the rinse pass afterwards.
The practical difference is time and consistency. A hood that used to need a soak, a scrub and a rinse can be cleared in a single pass, and the job can be done while the kitchen is shut down rather than taking up part of the next prep shift. Because the same equipment also handles the central kitchen degreasing work around the hood — the panels, the trough, the hood face, the stovetop surrounds and the floor edge under the line — one machine covers the whole exhaust-cleaning task instead of a bucket, a sink and a pile of brushes. If you are evaluating equipment for this duty, review the PowerDe steam cleaning machine range and the customized steam cleaning equipment service to match the machine to your hood layout and shift pattern.
Duct and fan: the part filters do not cover
Filters protect the duct; they do not eliminate buildup in it. Grease that gets past the filters coats the duct walls and the fan blades, and no cleaning routine for the filters reaches that. Plan for a separate, professional exhaust-duct and fan cleaning on a longer cycle, and keep the records for it. Where and how often depends on your local fire code and your insurer, so check both and write the required frequency into your routine rather than guessing it.
Write it down and assign it
The difference between a kitchen that keeps its filters and one that does not is usually the record, not the effort. Put the routine on a printed schedule sheet fixed inside the hood area, with a line for the date, the filter condition found, what was done, and who did it. Review it monthly. Three months of entries tells you whether your interval is right or whether the line is loading more grease than you assumed, and it gives you the documentation that inspection day requires.
Once the interval, the cycle and the record are in place, filter cleaning stops being a crisis job. It becomes a short, boring task on the schedule — which is exactly what a maintenance routine should be.
