Range Hood Not Working? Causes and Fixes

A range hood does more than most people give it credit for. It pulls smoke, steam, grease and cooking smells away from the cooktop, and on a ducted hood it carries them outside. When it stops working, the kitchen gets smoky and greasy quickly, and grease that builds up in a neglected hood is a fire risk.

Most range hood problems fall into a few groups: the filters, the fan and its motor, the duct and damper, the lights, and the controls. Here’s how to tell which one you’re dealing with, starting with the checks you can do yourself.

Ducted or recirculating? Know which hood you have

A ducted hood vents air outside through a duct to a wall or roof cap. A recirculating (ductless) hood pulls air through a charcoal filter and blows it back into the kitchen, and some models can be installed either way. It matters because the fixes differ: a ducted hood can have a blocked duct or a stuck damper, while a recirculating hood depends on its charcoal filter.

Start with the filters

Clogged filters are the most common reason a hood runs but barely pulls air. Metal mesh and baffle filters trap grease and need regular cleaning: with regular cooking, every month or two is typical, and many can go in the dishwasher (check your manual). Charcoal filters on recirculating hoods can’t be cleaned. They’re typically replaced every three to six months, or as your manual specifies, and a saturated one stops removing odours even though the fan still runs.

Fan won’t run at all

• Check the breaker, and whether the lights still work. Lights on but no fan points to the fan circuit, not the power supply.
• Try every speed. A fan that works on high but not on low, or the other way round, usually points to the speed switch or the control board.
• If the fan stops partway through cooking and starts again later, the motor may be overheating and tripping its thermal protection.
• A motor that hums but doesn’t turn may have seized bearings or, on some models, a failed capacitor.

Fan runs but suction is weak

• Clean or replace the filters first.
• On a ducted hood, check that the backdraft damper opens. It can stick shut with grease, or be blocked by a nest or ice at the outside wall or roof cap.
• Look for a crushed or disconnected duct section above the hood, which often happens during cabinet or ceiling work.
• Grease caked on the blower wheel reduces airflow and adds noise.

Loud, grinding or rattling fan

A gradual increase in noise is usually grease on the blower wheel throwing it off balance. A sudden grinding or squealing points to worn motor bearings. Rattling is often a loose filter, a loose mounting screw or a damper flapping in the wind. Re-seating the filters and tightening accessible screws is safe to do yourself; anything inside the blower housing is a job for a technician.

Lights not working

Start with the bulb. Hood bulbs run hot and burn out more often than you’d expect, and many hoods take a specific halogen or LED type, so match the replacement to your manual. If a new bulb doesn’t help, the socket, the light switch or, on LED hoods, the LED driver is the likely cause.

Buttons or controls not responding

Grease around buttons and touch panels is a common, easy fix: switch the hood off and clean the panel with a degreaser on a soft cloth. If the controls are still dead, the switch assembly or control board has likely failed. Some hoods also show a filter reminder that has to be reset after cleaning, which can make the controls seem stuck.

Burning smell, sparks or a tripping breaker

Stop using the hood and switch it off at the breaker. A burning smell usually means an overheating motor or damaged wiring, and both are safety issues, not just performance problems. If a pan catches fire, never use water on a grease fire: turn off the burner, cover the pan with a lid if it’s safe to do so, and call 911 if the fire doesn’t go out right away.

What you can safely do yourself

• Clean or replace the filters.
• Replace bulbs with the type your manual specifies.
• Wipe grease from the controls and the hood’s outer surfaces.
• Check the breaker and the outside vent cap.
• Tighten loose, accessible mounting screws.

Switch the hood off at the breaker before doing anything beyond changing filters.

When to call a technician

Book a repair if the fan still won’t run with power confirmed, if the motor hums, grinds or overheats, if the controls stay dead after cleaning, or if you notice a burning smell. A technician will test the motor, switches, control board and wiring, and give you a written price before any work starts. If your cooktop or oven is acting up too, see our stove and oven repair page.

Frequently Asked Questions