Installing an air filter correctly is essential for maintaining the quality of the air in your home. Fortunately, most air filters are designed with arrows printed on the sides that indicate the direction in which the air should flow. If your filter doesn't have arrows, you can look for the wire frame on one side of the filter and make sure it faces outward. It's important to routinely monitor your air filters to ensure they are not clogged with dirt, dust, or debris.
Fiberglass filters should be changed every 1 to 2 months and pleated paper filters should be changed every 3 to 5 months. Metal is usually placed behind the filter media to maintain its rigidity as air passes through it. No matter what type of HVAC system you have, each unit needs a quality filter to keep indoor air quality clean and your unit operating at peak efficiency. When you change the filter, make sure the arrows on the side of the air cleaner are pointing in the same direction as the airflow.
Additionally, if your oven filter has an option to “open or close” the vent, it's best to keep it open.