In general, it is recommended to have an air filter on each return grille for optimal air quality and to protect your HVAC equipment from dust, pollen, pet dander, and hair. Both return air filters and oven filters work the same way, cleaning the air as it circulates through the house and removing contaminants before the air passes through the HVAC equipment. Supply grilles should not have an air filter, as this can cause more problems than it solves. Many people are concerned that allergens will float around the house and cause allergy outbreaks, asthma attacks, and poor indoor air quality.
To prevent this, it is important to have a correctly sized return air filter that is properly installed. This filter will stay in place with Velcro strips until you are ready to remove and replace it. High-efficiency air filters with a MERV rating of 13 to 16 are not suitable for some standard heat pumps. In some older homes, it is common to have a return air vent and an air supply vent in each room.
If you have a standard size return grille in your home, you will be able to accommodate a regular rectangular shaped air cleaner. Filters protect HVAC equipment and capture a large amount of particles that would otherwise end up in the air you breathe. Installing a new filter is easy; simply slide the new component into the slot of the return air vent. Return vent filters help to filter contaminants so they don't enter your system in the first place.
However, if you need a replacement air or heating filter, shop with Filterbuy and have your new air filters delivered to your door. The core functionality of an oven filter is almost identical to that of an AC air filter, except that it applies to “hot air” rather than “cooled air”. As warm or cooled air enters the room, the “old” air needs to escape somewhere. We've had only a few customers over the years whose air conditioning contractor changed their system to use a whole-house filter without telling them to stop using the return ones.
However, return filters are important for overall indoor air quality and the health of your heat pump system.