Top Reasons Your Air Conditioner Is Not Removing Humidity

image of homeowner feeling hot due to air conditioner not removing humidity

Air conditioners have two ways of making spaces feel colder: lowering the room temperature and reducing indoor humidity. While most homeowners are only familiar with the former, the latter is equally important for comfort. High humidity levels can make people feel hot and sticky, even if the temperature has dropped. Air conditioning systems work silently in the background to address this issue. If the air conditioner not removing humidity, there may be an issue that requires attention from HVAC technicians. Before calling for professional assistance, you can quickly check the basics.

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Air Conditioners & Humidity Control

This guide will cover some of the reasons why your air conditioner may not effectively remove humidity from your home.

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How Air Conditioner Humidity Reduction Works

Air conditioning units are specifically designed to draw in hot and humid indoor air and pass it through cold evaporator coils. As the air travels through these coils, heat is absorbed, and the air is subsequently cooled. The moisture condenses on the coils, making the air less humid. Water droplets formed on the coils are collected in a drain pan and flow outside through a condensate drain line. Any interference with this process could cause the air conditioning unit to be ineffective in reducing humidity. As a result, the temperature may have dropped, but you may not feel comfortable.

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Why Is My Air Conditioner Not Removing Humidity?

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Although high humidity may not be an emergency, it can cause gradual damage to your furniture, wood floors, ceilings, walls, books, artwork, and indoor plants. It also creates a conducive environment for mold and mildew, which affects indoor air quality, creates unsightly spots, and spreads harmful spores. Ignoring high humidity can turn your house into an unhealthy and uncomfortable environment. Act quickly to prevent damage. Here are some potential causes of humidity failure in air conditioners:

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Thermostat Fan Setting

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To begin with a simple fix, you can check the thermostat fan settings. If your AC thermostat is set to ON, the fan will run continuously, preventing the cooling system from reducing humidity because it evaporates the water on the coils. The moisture will not flow down to the drain pan and condensate lines but will go back into the home. Setting the fan to AUTO runs only during the cooling cycle and stops afterward, allowing the water to exit the system correctly.

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Dirty Evaporator Coils

AC Unit Evaporator Coil

We have established the evaporator coils’ vital role in reducing indoor air humidity. However, the coils can become clogged with dirt, hindering condensation. When the coils are covered with a thick layer of dirt, they become insulated and less effective at cooling the surroundings. This can increase indoor temperature and humidity levels. Regular air conditioner maintenance can help prevent this issue. Have HVAC technicians visit at least once or twice a year to clean the coils and other components of the cooling system to ensure optimal performance.

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Refrigerant Leak

image of hvac contractor performing refrigerant refill on air conditioner

The refrigerant in an air conditioner that flows through the coils is responsible for absorbing indoor heat and releasing it outdoors. If there are leaks along the path of the refrigerant, the amount of refrigerant flowing will decrease until the cooling system cannot perform its duties. As a result, the cooling unit will be unable to cool the house or remove moisture from the air, and warm air will be blown from the vents. A hissing noise may also be audible from the system, and the air conditioner lines or the evaporator coil may be covered in ice.

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Faulty Ductwork

Although often overlooked, the condition of the ductwork in your air conditioning system is essential. Ductwork leaks are a common issue in homes, causing significant loss of conditioned air, which leads to inefficient operation and higher monthly energy bills. These leaks can also result in some rooms being cooler than others, indicating where the leaks may be located. Ductwork leaks can increase indoor humidity and decrease air quality. Because some ducts may be difficult to access, seek professional assistance to solve this issue.

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Oversized AC System

When it comes to cooling systems, bigger is not always better. It is vital to have a unit that is the right size for your home’s needs. If you install an AC system that is too large, your home may cool down too quickly, and the unit won’t run long enough to reduce indoor humidity. The AC may turn on and off frequently, harming the system’s components. To prevent this, choose the right size air conditioner for your home. Consult with a professional HVAC contractor for guidance.

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Proper humidity levels are just as essential as the temperature for a comfortable home environment. Air conditioning systems are engineered to handle both, but issues such as incorrect settings, dirty coils, leaky ducts, low refrigerant, and oversized systems can hamper their efficiency. If left unchecked, high humidity can cause harm to homes and individuals. For advanced solutions, seek the assistance of HVAC experts who can promptly restore the system to its optimal state. This way, you can bask in the comfort of a healthy living space.

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