Warning! To avoid personal injury or even death, always disconnect your appliance from its power source--that is, unplug it or break the connection at the circuit breaker or fuse box--before you do any troubleshooting or repair work on your appliance. Also, because some components may have sharp edges, use caution while working on your appliance.
If the fan doesn't work but the light does work, you probably have either a defective fan switch or a burned-out fan motor. You can replace either one without removing the vent hood from the wall, but you need to use an ohm meter to decide which component is defective.
The fan switch should have 0 ohms of resistance when switched on. If it doesn't, replace the switch. If it does, you need to replace the fan motor.
When the light doesn't work, it's usually because the bulb has burned out. If you replace the bulb and the light still doesn't work but the fan does work, either the light switch or the lamp-holder socket is defective. You can replace either of these without removing the vent hood from the wall.
Your vent hood is normally wired directly to your household electrical system (you don't plug it in). If the unit doesn't work at all, check for a blown fuse or a tripped circuit breaker.
When your fan runs at only one speed, it's either because of a partially defective fan motor or a defective fan switch. You can replace either of these without removing the vent hood from the wall, but you need to use an ohm meter to decide which component is defective.
The fan switch should have 0 ohms of resistance when switched on. If it doesn't, replace the switch. If it does, you need to replace the fan motor.
If your vent hood has a dimmer switch that adjusts the light intensity, but the dimmer doesn't work, the dimmer switch is probably defective. If so, you need to replace it.
Your vent hood may be one of the many that are meant to circulate the air but not remove it. Here's how you can tell:
If your unit has vent openings near the top, front of the unit, and air is blowing through these vents, you have a circulate-only type of hood.
If, when you check inside the cabinet above the vent hood, you see a metal duct leading away from the vent hood, you have a venting type. But if there's no duct, your unit may still vent through the back wall.
It's difficult to convert a circulating ventilation system so that it vents outside. You would need to run a metal duct from the vent hood either to an outside wall or through the roof of the house. We suggest you contact a qualified appliance installer, to determine whether a duct can be installed in your home.
