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Home / Air Filter Troubleshooting / Where are my air filters located?

Where are my air filters located?

Changing air filters regularly is a crucial piece of regular home maintenance, but for new homeowners, maintaining air filters can be one of those little jobs that goes undone because they don’t know much about them. Why are they important? What needs to be done? Where are they even located?

Check near the HVAC Unit

Some larger houses have more than one HVAC system, and each of these will have at least one filter. Take a look first for filters in or near the HVAC unit itself. These filters are most likely found next to the furnace or the air conditioning air handler. The HVAC unit can often be found in an attic, basement, or the back of a closet (somewhere out of the way). Once you’ve found the unit, look for a hinged or removable cover about one inch wide. It may be horizontally or vertically oriented, and you should find a filter already in place.

Air Filters in Return Air Vent

If you can’t find an air filter near your HVAC unit, then you may have to look in your return vent. Because HVAC units are often set up in a more difficult to access area, the filters are sometimes placed here for better accessibility. (Note: In a larger house, you may have air filters in both the HVAC unit and the return vent, so give it a look even if you’ve already found your filter in the HVAC unit.) Your return vent will be a large square or rectangle area, bigger than a typical air vent. They are found most often in a wall or a ceiling. To access the filter, pull off the cover of the return vent. This can be done either by unscrewing it, or prying it open with a coin or flat head screwdriver (if it is kept in place by a tab rather than screws).

How to Care for Air Filters

Whether referred to as a furnace filter, an HVAC filter, or an AC filter, realize that they are all exactly the same thing: an air filter. Air filters should be replaced every 30 days to once a year to ensure that indoor air quality remains high and to protect your HVAC system. The frequency of air filter replacement is determined by several factors.

  • Size of the home. For larger homes that circulate higher volumes of air, more airborne particles and debris will be trapped in the filter. The filters in larger homes should be changed more frequently.
  • Air Quality. Location and activity in the home can affect air quality. Indoor air quality can be decreased by: smoking in the home, use of a wood fire stove or furnace, burning scented candles, poor outdoor air quality, location near new construction sites, and excessive use of cleaning agents. If any of these apply to your residence, air filters would best be replaced every 30 days or so.
  • Respiratory health. If anyone in the home suffers from any kind of respiratory disorder, allergies, or asthma, be sure that you use a high-quality filter and check once a month.
  • Multiple pets. For a household with one pet, there shouldn’t be too much extra dander to contend with. But those who have multiple pets, check filters once a month to ensure that they haven’t been clogged with excessive hair or dander.

Frequency of replacement also depends on the type of filter that is used. The least expensive option is a fiberglass filter. These are disposable, and provide very basic levels of filtration. These should be replaced every 30 days.

Washable filters are the least common, and are not replaced but removed, washed, and then placed back in the system. These you may check every 6 months to a year, but they become more effective as surface particles build up.

Polyester or pleated filters are more common than washable, and more effective than fiberglass. They have a higher surface area than other filters and can work effectively for about 3 months to a year before replacement.

You may also choose air filters that offer solutions to individual needs. For example, a carbon filter will use activated carbon to filter out smoke and odors. These are also good for places where chemicals must be removed from the air. A HEPA filter has maximum levels of efficiency and is often used in hospital settings. These can be a good choice to filter a home if one of the residents has a respiratory disorder or allergies. If you are unsure of the type of air filter that’s best for your system, talk to an HVAC professional.

There is no standard size for air filters, so be sure that you measure yours before replacing.

Why are Air Filters Important?

Air filters perform an important function in the home. First and foremost, they keep the air that circulates within the house clean. Indoor spaces can become choked with pollutants and irritants like the following:

  • Pet dander/hair
  • Dust
  • Pollen
  • Mold
  • Smoke
  • Dust mites
  • Bacteria

Everyone’s health benefits from clean air, but filters become even more important to those in a household with allergies, immune deficiencies, or respiratory complaints such as asthma. Air filters clear the air of harmful particulates that can exacerbate these health concerns.

As if clean air in your home is not enough, air filters also offer the added benefit of extending the life of your HVAC system. They protect the system and allow it to run efficiently. In this vein, you will also save money by ensuring filters are clean...with the HVAC system working efficiently, and not having to force air through clogged filters, you can save money on your monthly heating and air conditioning bills.

Upon moving into a new home, make one of your first tasks finding your household air filters. Maintaining them is a simple, easy, and inexpensive way to keep indoor air quality high, and to ensure that your HVAC system is kept in good working order.

If you need air filter replacements, Filter King’s online store has every size you could imagine, in several different MERV levels and with many optional features for each of them!

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