Range Hood Fan Not Working

Light works, fan doesn’t

The light and the fan usually share the same power feed, so a working light rules out the breaker. What’s left:

• The fan switch or control. Push-button and touch controls wear out, especially the speed you use most. If one speed works and another doesn’t, the switch or board is the likely culprit. On some Broan push-button hoods, the blower won’t turn on at all if no speed button is pressed in, so press a speed first.
• The motor. Broan’s installation guides say the motor has a thermal overload that shuts it off when it overheats and restarts it once it cools. If it keeps shutting off and restarting, Broan says to have the hood serviced. A motor that hums but won’t spin needs a technician to test it.
• The blower wheel. Grease that gets past the filters builds up on the wheel until it drags or locks.
• A remote blower. Many high-end Bay Area kitchens have the blower in the attic, on the roof or inline in the duct. If yours does, the motor isn’t in the hood at all.

Nothing works

Check the breaker, and any wall switch that feeds the hood. Some hoods plug into an outlet inside the cabinet above; make sure the plug didn’t work loose. If the breaker trips again when the hood starts, leave it off and call.

Fan runs, but it’s weak or loud

• Filters. Broan says aluminum mesh filters should be washed about once a month, more if you fry or use a wok. Charcoal filters on non-ducted hoods can’t be washed; Broan says to replace them every three to six months.
• The damper. A flap in the duct or at the outside cap should open when the fan runs. Grease can glue it shut.
• Rattling or scraping. Usually a loose blower wheel, a bent blade or a bearing going bad.

What’s normal

• The fan turns on by itself. Many hoods have a heat sensor. Broan calls it Heat Sentry: when it senses too much heat over the cooktop, it turns the fan up to high and drops back once things cool down. That’s protection, not a fault.
• The fan keeps running after you cook. Some hoods have a delay-off timer. Check the manual before calling it a stuck switch.

Checks you can do

Turn the hood off at the breaker first. Then:

1. Pull the filters and wash them, or replace charcoal ones.
2. With a flashlight, look up at the blower wheel for heavy grease.
3. Check that the damper flap moves freely.
4. Restore power and try each fan speed, noting which ones work.

Don’t open the wiring box, test the switch with the power on or remove a blower motor yourself. Line-voltage wiring sits right next to all of these.

When to call

• The light works but no fan speed does
• The motor hums but won’t turn, or smells hot
• The breaker trips when the fan starts
• The fan won’t shut off with the controls
• A remote or inline blower has stopped

We repair existing range hoods: blowers, switches, controls and lights, including pro-style hoods over Wolf, Viking, Thermador and BlueStar ranges. We don’t install new hoods or run new ductwork.

See stove, range and cooktop repair and Viking appliance repair. If the burners under the hood won’t light, see gas stove won’t light. A visit is a $219 service call, free if you go with the repair, and you hear the exact price before any work (how pricing works). OEM parts, 90 days on parts and labor for qualifying repairs, and same-day weekday service is often available.

Bay Appliance Repair is an independent, locally owned repair company. Brand names belong to their owners.

Bay Appliance Repair, 140 San Pedro Rd, Daly City, CA 94014 · (415) 585-5900 · BEAR #46247 · Mon–Fri 8am–5pm. We come to you; there is no walk-in counter.

Common questions

Why does my range hood light work but not the fan?

Because the light proves power is reaching the hood, the problem is in the fan circuit. The usual suspects are the fan switch or control board, the motor or its capacitor, a tripped thermal cutoff, or a blower wheel jammed with grease. Clean the filters and try every speed. If none work, it needs a technician.

Why does my range hood turn on by itself?

Many hoods have a heat sensor that turns the fan on, or up to high, when it detects a lot of heat over the cooktop. Broan calls this Heat Sentry. The fan drops back or shuts off once the heat goes down. If the fan runs with the cooktop cold and won't turn off, that's a stuck control and a repair.

How often should I clean range hood filters?

Broan recommends washing aluminum mesh filters about once a month, and more often if you fry or cook with a wok. Baffle filters on pro-style hoods can go longer; wash them when they look greasy. Charcoal filters on recirculating hoods can't be washed and get replaced, usually every three to six months.