It may be difficult to locate on some HVAC systems, but you can find it in the return air duct. Or, in layman’s terms, that big metal grate on your wall, floor, ceiling, or utility closet door. Return air ducts can be just about anywhere. But usually, they are centrally located in the house.

Two-story houses may have one upstairs and another downstairs. In that case, they both need to be changed.

After Finding Your HVAC Filter

Once you’ve found the air filter, simply remove it and replace it with a new one. Depending on your filter type, you may need to do this every month or two. A general rule is to change your filter every 30 days, but I always tell people if the HVAC filter isn’t perfectly white, it’s time to change it. That’s the air you’re breathing! By taking this simple step, you can help improve the air quality in your home and extend the life of your HVAC system.

The return air duct or blower compartment in your HVAC system is responsible for circulating air throughout your home. Unlike the smaller vents around your home, the return air duct pulls in the air from your home and sends it to your HVAC unit to be heated or cooled.

Most Common Locations HVAC Filters

Depending on the type of HVAC system, the filter’s location will vary. Here are some of the most common locations for HVAC air filters:

  • Horizontal units: These units are frequently located in attics, basements, or garages. The filter usually fits in a slot on the air return side of the unit.
  • Vertical units: These units are often located in utility closets or crawl spaces. The filter is typically located behind a grille on the bottom or front of the unit.
  • Furnaces: Most furnaces have a dedicated compartment for the air filter, which is usually located near the blower motor.
  • Mini-Splits: Some houses have an air conditioning head in each room. Some are wall-mounted, and some are ceiling-mounted. Check those individual units for the air filters.

So, good on you for wondering where your HVAC filter is! The location of air return ducts can be important when considering installing a new HVAC system. That’s why they tend to be located in a hallway near the thermostat.

The primary purpose of ductwork is to move air throughout the house. The air return duct is responsible for bringing stale air back to the furnace or air conditioner to be filtered and recirculated. To function properly, the air return duct must be large enough to allow sufficient airflow. It is also important that the duct be located in a central location so it can draw air from all parts of the house. Unfortunately, finding air return ducts can be a bit like a scavenger hunt. They are often hidden behind doors or in other hard-to-reach places. But it’s worth the effort to walk around your entire house, looking high and low. Be sure to check behind doors and other hidden places so you don’t miss one. With a little patience, you should be able to find all of your home’s air return ducts.