Can a Dirty Air Filter Cause AC Not to Cool?

Professional Services
January 10, 2023

Replacing your air conditioner’s filter keeps your indoor air clean and your system running efficiently, but it can be hard to remember to change them every couple of months.


We’re here to answer the question, “can a dirty air filter cause an AC not to cool?” and explain everything you need to know about AC filters.


If your AC has stopped cooling efficiently, West Bend’s HVAC professionals at Professional Services can diagnose your problem and solve it, but first, check that it’s more than just a clogged air filter.


Why Isn’t My AC Working?

Can a dirty air filter cause the AC not to cool? There are a few major problems you could be having. Luckily, many issues are easy to solve as long as you catch them early:


  • If your home’s electricity is working fine, check the breaker to the AC.
  • If the airflow is low, you could have a faulty fan switch, which will require professional HVAC service.
  • If the air is warm or wet, you may have a clogged drain line, which you can clear yourself.
  • If you see puddles beneath your AC, you could also have a refrigerant leak.


A dirty air filter can happen in addition to these issues or even cause the issue. If your air conditioner is running but not cooling, you may have a dirty, clogged, or wrong-sized air filter.


The first step in diagnosing air conditioner problems is to make sure the filter is clean and placed properly. If your filter is dirty or misaligned, you’ll likely experience problems soon, if you’re not already having AC trouble.


Can a Dirty Air Filter Cause AC Not to Cool?

When the filter is dirty, your blower fan has to work harder, which can cause damage to several AC components. Your whole HVAC system relies on the open circulation of air to get cooler air where it needs to go. Any clog or dirt in your filter affects the whole system.


A dirty or clogged air filter will lower the quality of your air conditioning, as it strains to keep your house cool despite the extra workload. According to the Department of Energy, a clogged filter can increase your energy consumption by 5% to 15%. 


A clean filter allows air to circulate through the system, including the cooling coil or evaporator, where the cooling happens.

 

A dirty air filter can damage almost any part of the AC, from the blower motor to the evaporator coils, and cause it to break because it stresses all parts of the machine.


Problems with a Dirty Filter

Can a dirty air filter cause the AC not to cool? The answer is yes, and dirty filters can cause even more problems:


  • A frozen evaporator coil results from the lack of air flowing over the coil, which builds up cold air inside the coil, eventually freezing it. That’s a problem because your AC doesn’t just blow cool air in through your vents; it also pumps heat out from inside your home. A frozen coil can stall or break your AC and result in even higher temperatures.
  • Furnace failure is another consequence of dirty air filters. The heat exchanger builds up heat with nowhere to send it because the air filter is too clogged. Safety measures mean the furnace will shut down until the exchanger cools. If you don’t replace the air filter, this will keep happening, over and over, until the furnace breaks.
  • Health issues can also arise from dirty air filters. Your air filter’s primary job is to filter out allergens and contaminants. When that filter is clogged or dirty, those allergens circulate back into your breathing air. That means you’re more likely to get sick, especially if you’re allergic to things like dust, mold, or pollen. 


You should change your filters more regularly to keep your air clean and healthy if anyone in your home has allergies. You can even upgrade to a finer model of the same size filter to filter out smaller contaminants.


Save on AC Filter Replacement with Reusable Filters

Washable air filters are alternatives to disposable filters. Although reusable filters are more eco-friendly because you can wash and reuse them, they require special care, and there are a few pointers that everyone should know.


To clean a washable filter:


  1. Turn your AC or furnace system off and remove the filter from the unit.
  2. Rinse it with warm water, and gently remove all the sticky pollen and other particles from the surface. You can use a brush, but it should be a soft one.
  3. Rinse the filter with clean, warm water and shake it out to get out excess water.
  4. Don’t put it back in right away while it’s wet, or you might break your AC by causing ice formation. Let it dry in a well-ventilated or sunny spot, and don’t try to wipe it down. The filter is more delicate than it seems. 


Follow these tips, and you’ll have a reusable filter that will last for years.


Call Today for AC Filter Replacement and AC Service

The reduced efficiency of an air conditioning system with a dirty filter shortens the life of the whole system because each part is working harder to cool your home. If you let the problem go on long enough or put off having a professional visit, those problems will get worse and cause your AC not to cool. It’s better, and much simpler, to replace your filters every one to three months.


With proper care and regular maintenance, air conditioners should last an average of 20 years. It’s important to know when to get your AC serviced, so always check the filter and look out for the signs of more severe problems. 


At Professional Services, we’ve served West Bend since 2007. We can discover the cause of your AC troubles and help you eliminate them with our expert HVAC repair, installation, and other services.


Call Professional Services at 262-288-2941 to schedule AC maintenance or repair.

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