Commercial Kitchen
How to Clean a Commercial Range Hood Filter (and How Often)
Baffle vs Mesh, Soak Times, and the Fire Risk of Skipping It
Commercial baffle filters should be cleaned weekly to fortnightly depending on cooking volume, not monthly. They need to be soaked in a proper degreaser, rinsed and dried before refitting, and the canopy interior and duct need separate scheduled attention. Grease build up in filters and ducting is a leading cause of commercial kitchen fires, so the cleaning interval is a fire safety and insurance question, not a housekeeping one. Call 07 3888 7534 for a canopy assessment.
How often should a commercial range hood filter be cleaned?
Weekly to fortnightly for most venues, and more often for high volume fryers and chargrill operations. Monthly is too infrequent for a commercial kitchen, and it is the single most common compliance failure we see when a canopy has been in service for a year or two.
The interval should be set by grease loading, not by the calendar. A cafe doing breakfast and lunch will load its filters far more slowly than a pub with a continuous fryer. The practical test is visual and tactile: if the baffles are uniformly coated, if grease is bridging the gaps between vanes, or if the filter feels tacky rather than slick, it is due.
| Item | Interval | Who does it |
|---|---|---|
| Baffle filters | Weekly to fortnightly | Kitchen staff |
| Canopy interior and plenum | Monthly | Kitchen staff |
| Accessible ductwork | Monthly | Kitchen staff or contractor |
| Full duct system | 6 to 12 months, per insurer and fire risk assessment | Specialist contractor |
Our commercial range hood and exhaust canopy guide covers how the system is meant to be sized and specified in the first place.
What type of filter does your canopy have?
The cleaning method depends on this, and getting it wrong damages the filter.
Baffle filters
The standard in commercial kitchens. Stainless steel with interlocking vanes that force the air to change direction, throwing grease out by inertia. Durable, they do not clog like mesh, and they are designed to be cleaned and reused indefinitely.
Mesh filters
Lighter and cheaper, common in domestic canopies and lighter commercial units. They trap grease in the mesh itself, so they load up faster and are harder to clean thoroughly. They also degrade: the mesh distorts and the frame separates.
Charcoal or carbon filters
For recirculating canopies that do not vent outside. They cannot be cleaned, only replaced. Not acceptable for a commercial cooking operation in most jurisdictions, which is why a proper exhaust canopy is essential.
How do you clean a baffle filter properly?
In six steps, and the soak is the part people shortcut.
- 1
Remove the filters
Fan off, canopy cool. Note which way around they fit, because baffles are directional and refitting them backwards destroys their grease separation efficiency.
- 2
Scrape off loose grease
Into a waste container. Do not put heavy grease down a sink drain, it will set and block it.
- 3
Soak in a degreaser
Caustic based at the correct dilution and temperature, or an enzyme degreaser for a gentler cycle. 20 to 40 minutes for a well maintained filter, considerably longer for a neglected one.
- 4
Brush the vanes
Soft brush, working along the vane direction. Never steel wool or a carbon steel brush, which leaves free iron on the surface and causes rust spotting. See our guide to tea staining and stainless corrosion.
- 5
Rinse thoroughly
Clean hot water. Residual caustic left on the filter will attack the stainless and can contaminate food contact surfaces when the canopy runs.
- 6
Dry completely before refitting
Wet filters encourage corrosion in the plenum and can drip into the cooking area. While they are out, wipe down the plenum and the grease trough.
Can you put range hood filters in a dishwasher?
Small domestic mesh filters, generally yes. Commercial baffle filters, generally no.
A commercial baffle will not fit, will not be cleaned properly by a domestic cycle, and the detergent and rinse chemistry is designed for crockery rather than heavy grease. More importantly, running commercial kitchen grease through a dishwasher is a quick route to a blocked drain and a failed pump.
The soak tank is the right method, and most commercial kitchens should have one.
How do you know when a filter needs replacing?
Baffles are durable but not permanent. Replace them when the vanes are bent or deformed, when the frame no longer seats properly in the hood and allows air to bypass, when welds or rivets have failed, or when corrosion has pitted the surface so deeply that it can no longer be cleaned effectively.
Air bypass is the one that gets missed. A filter that does not seal properly lets grease laden air straight past it into the plenum and the duct, which is both a fire risk and a reason extraction performance drops. If the extraction feels weak despite clean filters, check the seating before assuming the fan is at fault.
What happens if you don’t clean them?
Three things, in order of seriousness.
Fire
Grease accumulated in filters, the plenum and the duct is fuel. Duct and plenum fires are among the most destructive events a commercial kitchen can experience, and they start in exactly the material that cleaning removes.
Loss of extraction
A loaded filter restricts airflow, so smoke, heat and grease stay in the kitchen. Staff end up working in a haze and the kitchen fails to remove heat, which affects both comfort and food safety.
Compliance and insurance
Cleaning records are routinely requested at health inspections and by insurers after an incident. An absence of records is difficult to argue with.
Grease build up in filters and ducting is a leading cause of commercial kitchen fires.
The cleaning interval is a fire safety and insurance question, not a housekeeping one. If grease is dripping from the filter into the plenum, it was due some time ago.
Does a dirty filter affect compliance and insurance?
It can affect both. Exhaust canopy systems are specified and installed to AS 1668.2, and food premises generally must be designed and constructed to AS 4674, which together establish an expectation of a cleanable, maintained ventilation system. A canopy that cannot extract because its filters are blocked is not performing as specified.
On the insurance side, most commercial policies include a condition requiring reasonable maintenance. After a grease fire, the first documents an assessor will ask for are the cleaning and maintenance records. Keeping a simple log, with dates, who did it and what was done, costs almost nothing and answers the question immediately.
If your canopy is old enough that the filters no longer seat, or the plenum has corrosion you cannot clean back, replacing the filters or the canopy is cheaper than the alternative. We fabricate stainless canopies to AS 1668.2 and supply replacement baffle sets to suit.
Frequently Asked Questions
How often should commercial kitchen hood filters be cleaned?
Weekly to fortnightly for most venues, more often for high volume frying and chargrilling. Monthly is not sufficient in a commercial kitchen.
What is the difference between baffle and mesh range hood filters?
Baffle filters use interlocking stainless vanes to separate grease by inertia and are the commercial standard. Mesh filters trap grease in the mesh and are suited to lighter domestic use.
Can baffle filters go in a dishwasher?
No. They will not fit, will not clean properly on a domestic cycle, and the grease will damage the machine and the drain. Soak them in a degreaser instead.
What is the best degreaser for range hood filters?
A caustic based degreaser at the manufacturer’s dilution and temperature, or an enzyme degreaser for a gentler cycle. Rinse thoroughly afterwards so no caustic remains on the stainless.
How do I stop my stainless filters rusting after cleaning?
Rinse off all chemical residue, dry fully before refitting, and never use steel wool or carbon steel brushes, which leave free iron on the surface.
How often should the exhaust duct be cleaned?
Accessible ductwork typically monthly and the full system on a specialist cycle set by your insurer and fire risk assessment, commonly every six to twelve months.
Do I need to keep cleaning records for health inspections?
Yes. Cleaning and maintenance records are routinely requested at inspection and by insurers after an incident. A simple dated log is sufficient.
Get Your Canopy Assessed
We fabricate stainless canopies to AS 1668.2 and supply replacement baffle sets to suit existing hoods. If the filters no longer seat or the plenum has corrosion you cannot clean back, we will tell you whether to replace the filters or the canopy. Call 07 3888 7534 or request a quote online.
Canopy Assessment and Replacement Filters
Book an assessment and we will check filter seating, plenum condition and whether the canopy still performs to specification.