Extractor Fan Runtime: How Long Should It Run and Why It Matters

When you turn on your extractor fan, a mechanical device designed to remove steam, smoke, grease, and odors from kitchens and bathrooms. Also known as range hood or exhaust fan, it’s not just a convenience—it’s a critical part of your home’s air quality system. Most people think if it’s running, it’s doing its job. But extractor fan runtime matters more than you think. Run it too short, and moisture and grease build up. Run it too long, and you waste energy and wear out the motor faster.

The right runtime isn’t a one-size-fits-all number. For cooking, run it for at least 20 minutes after you finish. That’s when steam and grease are still rising. For showers or bathrooms, 15-30 minutes after use helps prevent mold. If your fan shuts off automatically after 10 minutes, it’s probably not enough. Many older models lack timers, so you’re left guessing. That’s why extractor fan maintenance, regular cleaning and checking of airflow and motor function is so important. Grease clogs the blades, dust slows the motor, and a weak motor can’t pull air out fast enough—even if it runs for an hour.

And here’s the catch: if your fan is running constantly but still doesn’t clear the air, it’s not a runtime problem—it’s a extractor fan replacement, the process of installing a new unit when the old one can no longer perform effectively issue. Fans older than 10 years often lose suction power, even if they still spin. The motor wears out, the duct gets blocked, or the fan’s too small for the space. You can’t fix that with longer runtime. You need a better fan.

What you’ll find below are real-world guides from people who’ve dealt with this exact problem. How to clean a clogged motor before it fails. When to replace instead of repair. Why some fans last 15 years and others die in 5. And how to pick a new one that actually works. No fluff. No theory. Just what happens when you ignore runtime, what fixes actually work, and how to stop wasting money on broken fans.