Four Signals That Your AC Filter Needs Changing

Changing your AC’s air filter may not always be top of mind, but if you’ve forgotten to do it recently, your system may give you a little reminder with one of these signs:

  • Freezing or uneven cooling
  • Higher energy bill
  • Increased dust and allergens
  • Running longer than usual 

Freezing/Uneven Cooling

A clean air filter allows air to flow freely out of your unit. In contrast, a dirty air filter restricts airflow, causing it to build up inside the AC and lower the internal temperature. That buildup of cold air can eventually cause ice to form on the coils.

Even if the restricted air flow is not enough to cause freezing, it still isn’t good for your AC’s cooling power. You may begin to notice hot and cold spots around your home, resulting in less comfort and increased electricity bills for you.

Higher Energy Bill

If you recently opened your electricity bill and got a little shock, one explanation could be a dirty air filter. With a dirty filter, your AC is going to have to work longer and harder to cool your home, which means it will also use more energy. 

Increased Dust/Allergens

Have you started noticing more dust around your home? It could be an indication that your AC filter is dirty. 

Your air filter’s job is to catch dust and debris before they enter your AC system. Not only does this keep your AC system’s internal components clean, it also keeps the air circulating in your home clean. However, a clogged filter is ineffective at both of these tasks. It can cause extra wear and tear on the unit as well as poor air quality in your home.

Indoor air quality is of particular concern if you or your family members have trouble with asthma or environmental allergies. Over time, dirty filters cause allergens to build up in the duct system. Things like pet dander and cleaning chemicals can become trapped in the filter and released into the air months later – along with dust and other particles. Further, if a dirty filter is left for too long, it can also accumulate moisture, which can create a mold problem — a health hazard whether you suffer from allergies or not.

Running Longer

Does it seem like your AC is running for long periods of time? Your AC works by drawing in warm air (through the air filter) and stripping that air of heat. But, if the filter is clogged, your AC won’t be able to pull in as much air per cooling cycle. In turn, it will blow less cooled air into your home per cycle, requiring it to run longer to reach your set temperature. 

Changing Your AC Filters

Fortunately, changing your AC’s air filters is a relatively simple process. Here are a few tips:

If your AC has a reusable filter, remove it from the unit, rinse it off with water and allow it to air dry completely before putting it back in. This last step is important, because a wet filter can cause ice formation and other problems. Wiping the filter dry is not recommended because it can cause damage to its surface.

If your unit uses disposable filters, it is important to replace them with the type designed specifically for your system, not one-size-fits-all air filters from a hardware store. Buying factory authorized filters may be a little more expensive, but you’ll earn back the cost in increased system efficiency and performance.

Always consult your system’s manufacture for recommended filter cleaning/replacement schedules. It’s a good idea to check your filters every month. 

Finally, never run your air conditioner without a filter! This will allow dust and debris to build up on internal components, setting you up for maintenance issues in the future.