Which kind of hood do you have?
Turn the fan on high and check these in order.
- IfAir blows out of slots at the top front of a microwave above the rangeIt is set to recirculate. Odor goes through a small charcoal filter, if one is installed, and back into the room.
- IfNothing blows into the room and you can feel air leaving through an exterior wall or roof cap outsideIt is ducted outdoors. If smell still lingers, look at fan speed, filter cleanliness and how long it runs.
- IfThere is a duct above the cabinet but air still comes back into the kitchenThe unit may have been installed in recirculating mode despite the duct. Its manual explains how the blower plate is turned for outside venting.
- IfYou cannot find any exterior cap and the kitchen sits in the middle of the floor planRecirculation may have been the only option the builder chose. Ask an HVAC or kitchen contractor whether an exhaust route is practical.
Why recirculation is so common in attached homes
In an attached home, a kitchen may sit against a shared wall or near the center of a unit, far from an exterior wall. Running a duct outdoors could involve a ceiling route, a rated assembly, or association approval for a new exterior opening. A recirculating microwave hood avoids those construction questions, but whether that arrangement exists in a particular Lowry home must be checked at the appliance rather than assumed from the address.
The charcoal filters in these units are thin and small. They can take the edge off light cooking when new, but they saturate quickly and are frequently missing altogether. The fan then simply moves greasy, aromatic air around the kitchen and toward the stairs. Heavy searing, deep frying, fish and long-simmered spice blends overwhelm even a fresh filter.
Over months and years, that recirculated air leaves a thin film of cooking oils on cabinet faces, the ceiling above the range, upper walls, window coverings and the fabrics in nearby rooms. The film holds aroma long after the meal, which is why a kitchen can smell of cumin or fried fish on a morning when nothing has been cooked.
Options from simplest to most involved
- Option
- Replace the charcoal filter
- What it does
- Restores what little odor capture the unit had
- Limits
- Short-lived; still returns air to the room
- Option
- Run the fan longer and higher
- What it does
- Moves more air across the filter and helps mixing
- Limits
- Does not remove odor from the house
- Option
- Open a window or run a bath fan while cooking
- What it does
- Creates an outward path for cooking air
- Limits
- Weather-dependent; bath fans are small
- Option
- Cover pots and use lower heat for searing
- What it does
- Reduces the amount of oil and aroma released
- Limits
- Changes cooking habits
- Option
- Convert to outside venting where a duct route exists
- What it does
- Removes cooking air from the home
- Limits
- May need a contractor and, in an association, written approval
- Option
- Clean the film already built up
- What it does
- Removes stored odor from cabinets, walls and fabrics
- Limits
- Needed once even after the hood is fixed
Before you ask anyone about changing the hood
- Find the model number inside the microwave door or under the hood and download the manual
- Check whether an exterior wall or roof cap already exists anywhere near the kitchen
- Read your association's rules on exterior penetrations and contractor work
- Photograph the cabinet above the hood with the shelf removed to show any duct
- Note how often heavy cooking happens, so the conversation is about real use
Common questions
Will a stronger recirculating unit fix the problem?
Usually not. More airflow through a small carbon filter still sends most aroma back into the room. Getting air outdoors is what makes the real difference.
General information for Lowry, not a quote or professional advice. In an emergency, call 911.