Kitchen Chimney Not Sucking Smoke? Common Causes
A chimney that's struggling to clear smoke and odour is rarely a sign it needs replacing — in most cases it's a maintenance issue that's built up gradually, and it's one of the more overlooked kitchen appliances until it stops working properly.
Clogged Grease Filters
The mesh or baffle filters trap grease particles before air is pulled through the motor. Once caked in grease, they choke airflow badly, and this is by far the most common reason for weak suction. Filters typically need washing every 2–4 weeks with regular cooking, more often for heavy frying/tadka use.
Blocked or Kinked Exhaust Ducting
If the filters are clean but suction is still weak, check the ducting running from the chimney to outside — a sharp bend, a bird's nest, or accumulated grease inside the pipe itself can restrict airflow just as much as a dirty filter.
Motor Running but Weak Suction
If you can hear the motor running at what sounds like normal speed but there's little pull, the issue is almost always upstream — filters or ducting — rather than the motor itself losing power.
Unusually Loud or Rattling Motor
A motor that's become noticeably louder, or has developed a rattle or grinding sound, often points to worn motor bearings — this typically needs a technician rather than a filter clean, and is worth addressing before the motor fails completely.
Chimney Not Turning On at All
Check the power connection and control panel first — loose connections are common given the heat and grease exposure near the hob. If power is confirmed and it still won't start, it's likely a control board or motor fault.
Oil Collector Overflowing
Many chimneys have a small oil/grease collection cup — if this hasn't been emptied in a while, it can overflow onto the hob or affect suction indirectly. A simple, easy-to-miss maintenance item.
Try This First
Quick Checks You Can Do Yourself
Safe to check before booking a technician — if none of these fix it, at least you'll know what to tell us on the call.
Remove and soak filters in hot water with dish soap — visible grease build-up is the most common cause of weak suction.
Look for any visible kink, disconnection or blockage in the pipe running from the chimney to outside.
If your chimney has one, check whether it's full and needs emptying.
Note whether it sounds normal, weak, or unusually loud/rattling — this helps narrow down filter/duct vs. motor issues.
FAQ
Common Questions
How often should chimney filters really be cleaned?
Every 2–4 weeks for regular daily cooking, and more frequently if you fry often or use a lot of oil/spices — mesh filters especially clog fast under heavy use.
Is a loud chimney motor dangerous?
Not immediately dangerous, but a new rattle or grinding sound usually means worn bearings that will eventually fail — worth getting checked before it stops working entirely.
Can I clean the ducting myself?
The visible/reachable sections, yes, but ducting that runs through a wall or a long path is best checked by a technician, since it often needs partial disassembly.
Does filter type (mesh vs. baffle vs. auto-clean) change how often it needs service?
Auto-clean chimneys need far less manual filter washing, but the ducting, motor and oil collector still need periodic checks regardless of filter type.
Still Not Fixed?