Range hood weak suction?

A hood that runs but barely pulls smoke and grease is most often held back by clogged grease filters. If you have a recirculating hood, it doesn't vent outside at all, and its charcoal filter may be due. After that, look at the damper, the duct and the outside vent cap.

Not sure which one it is? Snap your range hood and we’ll narrow it down.

Does the fan or light not come on at all?

A hood that won't run has different causes from weak suction. Range hood not working

Likely causes

Grease-clogged filters
Most commonEasy DIY
The metal mesh filters look greasy or caked, and the hood pulls less than it used to. Grease buildup is also a fire risk.
Charcoal filter due (recirculating hood)
CommonEasy DIY
The hood has no duct to the outside and blows air back into the kitchen. Cooking smells linger because the charcoal filter is spent, even with clean grease filters.
Stuck backdraft damper
CommonModerate DIY
The flap in the duct opening doesn't swing open when the fan runs, or hangs partly shut from grease.
Crushed, blocked or very long duct
Less commonCall a pro
The hood pulls weakly from the day it was installed, or got worse after work in the attic or wall. A crushed section, many bends or a very long run to the outside all choke the airflow.
Blocked outside vent cap
Less commonModerate DIY
From outside, the cap is clogged with grease or a nest, or its flap is stuck shut, and the hood pulls weakly or smells of cooking.
Running it on low or turning it on too late
CommonEasy DIY
It seems fine for light cooking but can't keep up with frying or searing. Switching it on after smoke has already spread leaves it chasing the smoke.

Quick checks

Switch off the breaker or unplug the hood before working on it beyond the filters. Grease buildup is a fire risk, so keep the filters clean. For a grease fire on the stove, turn off the burner and cover the pan with a lid. Never use water.

Turn the hood off, let the stove cool, and take the grease filters out. If they are greasy, wash them according to the hood's manual and let them dry.
If the hood doesn't vent outside, find the charcoal filter and check whether it is due for replacement.
Turn it on before you start cooking and try a higher speed.
With the fan running, look at the damper flap and see whether it opens.
If you can see the outside vent cap, check for grease or a nest blocking it.
Write down the model number, and take photos of the filters and the outside cap.

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Snap one of these:

the hood from below with the filters in place
the filters close up
the outside vent cap, if you can see it

Add a note or more photos next. Nobody calls you.

When to call a pro

Clean filters and a clear cap don't help, the damper is stuck, or the duct looks crushed, blocked or very long. A hood over 10 years old with a weak fan is worth pricing against replacement. If it won't run at all, see range hood not working. For lifespan and upkeep, see the range hood guide.

Typical cost: $85–210 for a minor repair, parts and labor included, and $300–500 for a more extensive repair. A new hood installed runs $650–2,500, and replacing is worth considering once the hood is over 10 years old. Range hoods last about 15 years (10–20).

Sources: HomeAdvisor: Who to hire to fix a range hood (updated November 5, 2025), Angi: Range hood (no update date shown)

After a scan, Fixology can also help you find pros near you.