· Expert Exhaust Cleaning · Range Hoods · 5 min read
7 Signs Your Commercial Kitchen Canopy Needs Cleaning
From grease dripping off the filters to a fan that roars but pulls nothing, here are the seven warning signs your commercial kitchen canopy is overdue for a professional clean.
Your commercial kitchen canopy needs cleaning when you see grease pooling on the hood or filters, notice weak extraction or lingering smoke, smell a rancid grease odour, or hear the fan straining. Any one of these means grease has built up past the point the system can manage. The safe rule for most Sydney kitchens is a professional canopy clean every 3 to 6 months, sooner for high-volume frying or solid fuel.
What are the 7 signs your kitchen canopy needs cleaning?
The clearest signs your kitchen canopy needs cleaning are visible grease, weak airflow, odour, a labouring fan, sticky surrounding surfaces, filters that stay greasy after washing, and no service record in the last six months. Each one points to grease sitting where it should not.
| # | Sign | What it means | Urgency |
|---|---|---|---|
| 1 | Grease drips or pools on the canopy and filters | Filters are saturated and grease is running back over the cookline | High |
| 2 | Weak extraction, smoke or steam lingering | Clogged filters and duct are choking airflow | High |
| 3 | Rancid or greasy smell in the kitchen | Old grease is oxidising in the plenum instead of being pulled away | Medium |
| 4 | The fan is louder or straining | A grease-loaded impeller is out of balance and overworking | High |
| 5 | Sticky, discoloured walls and surfaces near the hood | Aerosolised grease is escaping the capture zone | Medium |
| 6 | Filters stay greasy after washing, or are warped | Filters are past service life and no longer capturing grease | Medium |
| 7 | No clean or certificate in the last 6 months | You are outside AS 1851 documentation and likely insurer terms | High |
Why does visible grease on the canopy matter most?
Visible grease is the single most important sign because it is fuel sitting directly above open flame. When filters saturate, grease stops draining into the collection tray and instead coats the canopy face and drips back onto the cookline. Grease build-up is the leading cause of commercial kitchen fires, so removing it removes the primary ignition fuel.
Is weak extraction a sign the canopy needs cleaning?
Yes. If smoke hangs in the kitchen or the space feels hotter and steamier than usual, restricted airflow is the reason. Grease narrows the filter slots and duct bore, so the same fan moves far less air. AS/NZS 1668.1 sets the mechanical ventilation design your system was built to, and a grease-loaded canopy no longer meets it.
What does a straining fan tell you?
A louder or vibrating exhaust fan means grease has loaded the impeller and thrown it out of balance. The motor then draws more current, runs hotter and wears its bearings faster, which raises both your energy bill and the risk of a mid-service breakdown. Cleaning the fan and cowl restores balance and airflow in one step.
How often should a commercial kitchen canopy be cleaned?
Most commercial kitchens need a full canopy clean every 3 to 6 months, because that is the window in which grease reaches a hazardous depth under normal cooking. Higher heat and more frying shorten it. The table below matches frequency to cooking type, with filters cleaned in-house between professional visits.
| Cooking type | Filters | Canopy & plenum | Duct & fan |
|---|---|---|---|
| Solid fuel, charcoal, wok, high-volume frying | Weekly to monthly | Monthly | Quarterly |
| Busy restaurant, burgers, fried foods | Monthly | Quarterly | Every 3–6 months |
| Standard café or bistro | Monthly | Every 3–6 months | Every 6 months |
| Light use, reheating, minimal frying | Monthly | Every 6 months | Every 6–12 months |
Charcoal and wok kitchens sit at the top of the table because they produce more airborne grease at higher temperatures, so the duct loads far faster than a café’s. If you run one of these, treat monthly filters and quarterly duct as a baseline, not a target. For a deeper breakdown, see how often to clean commercial rangehood filters in Sydney.
Why does canopy grease build-up matter for fire and compliance?
Grease build-up matters because it is combustible, and a canopy fire travels straight into the duct where it is hard to reach and easy to spread between floors. Removing grease reduces fire risk directly, because grease is the fuel a spark needs. It also keeps you inside your obligations.
Australian Standard AS 1851 covers the routine service of fire protection systems and sets the expectation that kitchen exhaust cleaning is documented, dated and certified. AS/NZS 1668.1 governs how the ventilation was designed to move air. A clean, certified system satisfies both, which matters when an insurer or fire authority asks for records after an incident. The right filter also helps here, so if you are unsure which you have, read baffle versus mesh filters for commercial kitchens.
What does a canopy clean cost in Sydney?
A single-canopy clean in Sydney starts from around $390, a canopy-plus-duct system runs $900 to $2,500, and a multi-storey riser starts at $3,000 and up. Price is driven by canopy count, duct length, roof access and whether compliant access panels already exist.
| Scope | Typical price (AUD) |
|---|---|
| Single canopy, filters and plenum | from ~$390 |
| Canopy plus duct and fan | $900–$2,500 |
| Multi-storey riser and roof plant | $3,000+ |
A cheap wipe-down changes almost nothing about your grease load, because it never opens the plenum or reaches the duct. A full clean strips the canopy, soaks the filters in a heated tank, brushes the duct back to metal and certifies the result, which is what actually lowers your fire risk and satisfies AS 1851. Our range hood filter & vent cleaning covers each of these steps.
Book before the next sign appears
If your canopy shows even one of these seven signs, do not wait for the second. Get a same-day quote or call us on 0468 070 392, and we will confirm scope, price and a certificate before we leave the site.
