--- title: "Microwave-hood vent repair" description: "JennAir microwave-hood vent repair: the fan on an over-the-range unit no longer clearing the cooktop." url: "https://jennairmiami.support/services/microwave-hood-vent-repair/" date_modified: "2026-08-24" Appliance type: "Cooktops and rangetops, Microwaves, Ranges" --- # JennAir microwave-hood vent repair ### Two appliances, one box An over-the-range microwave is a microwave and a ventilation hood sharing a cabinet, a power supply and a control. That has one practical consequence worth knowing: a dead microwave is a dead hood, and the reverse is not true. A fan that has stopped while the microwave heats perfectly is a hood repair, and it is the cheapest visit on this site. ### The question almost nobody can answer Is it ducted or recirculating? A ducted unit sends the air outside. A recirculating one puts it back into the room through a charcoal filter that traps what it can. The second kind is extremely common in condominiums, and when its filter is saturated the fan works and nothing is removed — the exact complaint people call about. Charcoal filters are replaced, never washed, and half a year to a year is a realistic interval in a kitchen in use. ### What goes wrong - **Grease filters**, which wash and are the free half of this work. - **The charcoal filter** on a recirculating unit, which is replaced. - **The blower motor and its capacitor** — a hum with no rotation is usually the second. - **The damper**, on a ducted installation. - **The switch or control**, on a fan that shows no sign of life at all. ### What it costs From $135, and a good share of these end at a filter. Confirmed after the diagnostic and agreed before anything is opened. What this involves Filters and the ducted-or-recirculating question first Blower, damper and switch measured in that order A dead microwave means a dead hood, and the reverse is not true Ducted or recirculating The single most useful thing to establish, and most owners do not know which they have. A recirculating installation puts the air back into the room through a charcoal filter, and when that filter is saturated the fan works perfectly and achieves nothing. The grease filters underneath, which wash, and the charcoal filter if there is one, which does not — it is replaced. Between them they are most of this work. The damper and the duct On a ducted installation, whether the damper opens and where the run actually goes. Both are outside the appliance and both stop it working. Then blower and switch A hum with no rotation is usually a capacitor. No hum at all is usually the switch or the control. Neither is expensive. Two appliances, one box An over-the-range microwave is a microwave and a ventilation hood sharing a cabinet, a power supply and a control. That has one practical consequence worth knowing: a dead microwave is a dead hood, and the reverse is not true. A fan that has stopped while the microwave heats perfectly is a hood repair, and it is the cheapest visit on this site. The question almost nobody can answer Is it ducted or recirculating? A ducted unit sends the air outside. A recirculating one puts it back into the room through a charcoal filter that traps what it can. The second kind is extremely common in condominiums, and when its filter is saturated the fan works and nothing is removed — the exact complaint people call about. Charcoal filters are replaced, never washed, and half a year to a year is a realistic interval in a kitchen in use. What goes wrong Grease filters, which wash and are the free half of this work. The charcoal filter on a recirculating unit, which is replaced. The blower motor and its capacitor — a hum with no rotation is usually the second. The damper, on a ducted installation. The switch or control, on a fan that shows no sign of life at all. What it costs From $135, and a good share of these end at a filter. Confirmed after the diagnostic and agreed before anything is opened. ### The fan runs but the steam stays. Start with the filters underneath, which want washing far more often than people expect. Then find out whether the unit is ducted outside or recirculating through a charcoal filter — a recirculating unit with a saturated filter moves air and removes nothing, which is exactly what that sentence describes. ### The microwave is dead and so is the fan. Expected: on an over-the-range unit they are one appliance sharing one supply and one control, so a dead microwave is a dead hood. The reverse is not true — a fan that has stopped while the microwave works is a hood problem on its own and a smaller repair. ### How often do the charcoal filters need changing? Every six months to a year in a kitchen in real use, and they are not washable — washing a charcoal filter is the commonest mistake with these units. If you have never changed yours and the unit recirculates, that is the first thing to try and it costs less than a call. ### The fan hums but the blades do not turn. Usually a capacitor, which is a small and common part. A blower that neither hums nor turns is more often the switch or the control. Telling us which of those you hear narrows it before anybody arrives. --- **[Read full article: Microwave-hood vent repair](https://jennairmiami.support/services/microwave-hood-vent-repair/)**