Sings of a Dirty AC Air Filter

If you’re like most people, you probably don’t think about your home’s HVAC filter until it’s time to change…
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If you’re like most people, you probably don’t think about your home’s HVAC filter until it’s time to change it. And even then, you might only consider changing it when it’s visibly dirty. However, there are several signs that can indicate it’s time for a new filter, regardless of how dirty it looks.

Your air filter serves an important function in the process of heating and cooling your home. As the system pulls air in from your home, the air filter catches and traps dirt, dust, pollen, pet dander, and other allergens and pollutants. This is imperative for indoor air quality and for preventing certain respiratory triggers. If your air filter gets dirty or clogged, airborne particles can circulate in your home and cause your HVAC system to work harder and less efficiently.

Depending on the type of filters you have, you need to clean or change your filter at least every three months. You can follow the manufacturer’s directions for understanding how to clean an AC filter. If you have disposable filters, you need to ensure that you change them out with ones that are the right size and type. So how do you know when it is time to change your air filters? Let’s take a look at some signs that indicate you have dirty air filters.

Warm Air


A hallmark of a dirty air filter is an inefficient air conditioning system. If you notice that your AC unit isn’t cooling as well as it normally does or that it is blowing warm air, you should check your air filter first. If the filters become dirty or clogged, the AC will not be able to cool the air as efficiently. This is because the dirty filters block the airflow, which makes the AC work harder. In some cases, a severely blocked air filter could completely prevent your air conditioning unit from circulating any air at all. This puts a great strain on your system and could lead to equipment failure.

Warm Unit

One clear sign that your AC filter needs replacing is when the back of the unit is too hot. A clogged filter will prevent the air from flowing through the unit properly, leading to a rise in temperature. If the filter is very dirty, you may even notice warm air coming from the back of the unit. A clogged filter forces your unit to work harder to maintain a comfortable temperature in your home.

Poor Air Quality


If you feel as though you are battling allergies or more frequent asthma flare-ups, it could mean that you have developed poor indoor air quality. As discussed, your air filter is responsible for trapping airborne allergens and pollutants. If you have a dirty or clogged filter, you could experience a number of issues, including increased allergies, respiratory problems, eye irritation, and nose and throat irritation. If the air inside your home has become uncomfortable with allergens or other particles, it is a sign that you need to check your air filter.

Dust Buildup


Another common sign that you need to change the air filter is finding excessive dust on surfaces and furniture near the vents. Under normal circumstances, you are aware of how dusty your home can become. Usually, dust buildup around your home is a product of many factors including environmental and geographical impacts. However, if your HVAC filter is dirty, you may notice an unusual amount of dust. This is because the dirty air filter is not doing its job of trapping dust and other particles, which are then recirculated throughout your home.

A clean HVAC filter is important for keeping your home’s air clean and healthy. While you’ll want to check your filter at least every three months, other factors like the size of your home, location, and the number of pets might require more frequent changes.