Published March 31, 2026 Uncategorized
Your extractor fan works hard every time you cook — pulling grease, steam and cooking fumes up and out of your kitchen. The problem is that most of what it pulls in doesn’t disappear. It builds up. And over time, a dirty extractor fan stops being a minor inconvenience and starts being a genuine problem.
Here’s how to tell when yours needs attention.
The filters are visibly clogged
The most obvious sign is the filters themselves. Pull them out and have a look. If they’re matted with grey, sticky residue, they need cleaning. A lot of the grease from cooking turns into fine particles as it heats up — almost like a vapour — and floats around the kitchen. Your extractor sucks it up, and the filters catch it. Over time they become blocked, which means the extractor can no longer do its job properly.
You can put most metal filters through the dishwasher, and that will deal with light build-up. Bear in mind that aluminium filters can dull down depending on the dishwasher tablets you use, but they’ll still function. For heavy build-up, a dishwasher often won’t cut it — the grease is simply too thick and baked on. That’s when a proper dip tank makes the difference.
The outside and underside are coated in grease
People tend to focus on the filters, but the build-up doesn’t stop there. Grease gets onto the external surfaces of the extractor, onto the underside, and into the interior housing. When you touch it and your hand comes away sticky or grey, it’s overdue a clean.
A proper professional clean covers all of it — filters, the inside of the extractor, the underside, the light covers, and the external surfaces. Not just a quick wipe of the filters and leaving everything else.
Fat is dripping from the filters
This is the point where it moves from inconvenience to hazard. When the build-up is heavy enough, melted fat can start to drip through or from the filters onto the hob below.
On an induction hob, this is unpleasant but not immediately dangerous. On a gas hob, it’s a different matter entirely. Fat dripping onto a lit gas burner is one of the most common causes of kitchen fires. The fat hits the flame and ignites — the result can be a sudden ball of flame. This is not a theoretical risk. It happens.
If fat is dripping from your extractor, get it cleaned as a matter of urgency.
It’s not extracting properly
If you’ve noticed that your kitchen fills with steam or cooking smells more than it used to, even with the extractor running, the filters are likely so blocked that air can barely pass through them. The extractor is running but not doing anything useful.
The fan motor
This is the one to take seriously as a long-term warning. Grease doesn’t just coat the filters and the visible surfaces — over time it gets drawn further into the unit and can reach the motor. Once grease gets into the motor, it can’t be cleaned out. An electrician will tell you the same thing — at that point, the motor needs replacing.
The good news is that regular cleaning prevents this entirely. The extractor does its job, the filters get cleaned before the build-up becomes extreme, and the motor never gets near that level of contamination.
How often should an extractor fan be cleaned?
For most households, once a year as part of an oven clean makes sense. If you cook frequently, use the hob for a lot of high-heat or high-fat cooking, or have a gas hob, more regular attention to the filters is worthwhile.
If your extractor fan is overdue a clean and you’re in Norfolk, we can deal with it as part of an oven clean or as a standalone job. Give us a call on 07545 915652 or see our prices page for details.