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Why Dust Is Your Air Conditioner’s Worst Enemy

Serving Families Throughout Dallas
dusty air filter

HVAC professionals and experts at the U.S. Department of Energy recommend annual maintenance to prevent your air conditioner from losing efficiency and breaking down. You might be wondering, “But what causes my air conditioner to lose efficiency in the first place?” While an air conditioning system can become less efficient due to factors such as air duct leaks, loose parts, and lack of lubrication, dust is one of the leading causes of HVAC issues.


Dirt is dust’s main ingredient, but household dust is also comprised of things like dead skin cells, hair, pollen, tiny plastic specks, carpet and textile fibers, bacteria, and often dust mites. Research shows that most dust in your home comes from outdoors, but certain conditions inside your home can worsen a dust issue.


Dust can have numerous adverse effects on your air conditioner. Below are three critical areas where dust has the most significant negative impact.

1. Clogged Air Filter

Your HVAC system’s air filter protects the system’s machinery from airborne particles that would otherwise enter through your home’s return vent. However, if the filter becomes clogged with dust, it will not allow adequate airflow through your system. A lack of airflow can result in cooling issues and can even cause your AC to overheat and break down.

2. Frozen Evaporator Coil

Your air conditioner's evaporator coil contains refrigerant; as your system blows warm air across the coil, the refrigerant absorbs the air's heat, thereby making the air cooler. If your system's air filter is clogged and restricting airflow, the evaporator coil can get too cold and freeze.

Dust can also clog your evaporator coil’s condensate drain line. When this drain line is blocked, all of the moisture that the evaporator coil makes during the cooling process has nowhere to go, and it can freeze around the coil.

3. Dirty, Inefficient Condenser Coil

Above, we talked about how refrigerant in your AC’s evaporator coil absorbs heat from your home’s air. That heat gets released outside your home by the condenser coil in your AC’s outdoor unit. Condenser coils have a much harder time releasing that heat when they’re caked in dust. The dirtier your system’s condenser coil is, the less efficient it becomes, and the more money it will cost you to cool your home.


Experts agree that the best way to keep dust from negatively effecting your air conditioner is to change your air filter frequently and schedule annual maintenance for your system. You'll save your system from premature wear-and-tear, you'll save money on your energy bill, and you'll have an air conditioner that's able to cool your home more effectively and efficiently.

For trustworthy AC maintenance in Richardson, TX, you can count on our reliable team at Rescue Air and Plumbing: (972) 201-3253. If you're part of our Service Club Membership, don't forget that you get two free tune-ups a year!