From a technician’s point of view, this problem makes more sense once you know what your air conditioner is actually doing. Air conditioning is not just about cold air. It is also about moisture removal.
Air conditioning systems draw warm, moisture-filled air from inside your home and pass it over cold evaporator coils, which cools the air and causes moisture to condense into water droplets. In other words, warm indoor air passes across the indoor coil, the evaporator coil gets below the dew point, and moisture becomes liquid water. That water should drip into a drain pan and leave through the condensate drain line.
When functioning properly, an air conditioner keeps indoor humidity levels between 30% and 50%, which is considered the comfort zone by most experts. The ac system must move enough air and run long enough through its cooling cycles to cool air, remove moisture, and reduce humidity. In Metro Atlanta summer heat, even a small issue can leave humid air in the living space.
Before calling for service, try these safe checks. They often reveal why your hvac system is not effectively removing humidity.
Many humidity issues in Metro Atlanta homes start with a simple fan setting. If the thermostat fan is set to 'ON' instead of 'AUTO', it can cause humid air to be blown back into the home, preventing effective moisture removal from the air conditioning system.
Here is why. When the fan is set to ON, it runs after the compressor shuts off. That moving warm air blows across wet coils and sends moisture back into the house instead of letting it drain away. If the thermostat fan is on AUTO, the blower and compressor run together, helping remove excess moisture between cycles.
Very low setpoints can also hurt humidity control. The ac unit may hit the right temperature too quickly and shut off before it has removed enough moisture. Using a designated "Dry Mode" on a thermostat can prioritize dehumidification over maximum cooling. Ragsdale can help set up smart thermostats and Wi-Fi controls for better comfort.
Anything that chokes airflow through the air conditioning system will hurt its ability to remove humidity. Restricted airflow due to dirty coils or clogged filters can prevent evaporator coils from condensing water vapor effectively.
A clogged air filter slows airflow across the evaporator coils. That can lead to cold but damp air, frozen coils, less moisture removal, and eventually ice buildup. Regular maintenance, including cleaning evaporator coils and replacing air filters, is essential for ensuring your air conditioner effectively removes humidity.
Dirty evaporator coils are another common cause of high indoor humidity. Dust, pollen, and biofilm insulate the coil so it cannot collect enough moisture from warm indoor air. Leaky ductwork can introduce humid air from attics or crawl spaces into the home, making it difficult for the air conditioning system to maintain proper humidity levels. Duct leaks can also waste conditioned air and lower the system's efficiency.
Some problems are not homeowner fixes. Low refrigerant levels can reduce an HVAC system's capability to absorb and remove moisture, which can lead to cold but clammy air. The system needs the correct refrigerant charge and proper refrigerant levels for the evaporator coil to get cold enough.
Symptoms of a refrigerant leak or other refrigerant issues include long run times, poor humidity control, ice on the refrigerant lines, uneven cooling, hissing sounds, or an ac running without delivering indoor comfort. A clogged condensate drain or cracked pan can cause water backup, musty smells, shutdowns, and excessive humidity because the unit is not removing all the moisture safely.
Other causes include failing blower motors, normal wear, dirty outdoor unit coils, or a stuck expansion valve. A licensed hvac professional from Ragsdale uses gauges, leak detection, airflow testing, and drain cleaning tools to diagnose the entire system safely.
Even a good installation can struggle with controlling humidity if size and run time do not match the home. If your air conditioning system is oversized, it may cool the space too quickly without removing enough humidity, leading to a clammy environment.
An air conditioner that is too large for a home can cool the space quickly but may not run long enough to effectively remove humidity, leading to a damp indoor environment. An air conditioning unit that is too large for a home can cool the space quickly but may not run long enough to effectively remove humidity, leading to a damp indoor environment. Improperly sized air conditioning units can lead to short cycling, which prevents the system from running long enough to dehumidify the air effectively, resulting in high indoor humidity levels. This is called short cycling.
An undersized air conditioning unit may struggle to cool the space adequately, which can also lead to high humidity levels as it fails to remove moisture effectively from the air. Ragsdale performs Manual J load calculations and reviews insulation, windows, duct layout, and air leaks before recommending a replacement ac unit.
Some homes need more than basic cooling, especially older homes with crawl spaces, basements, or frequent moisture problems. Integrating a whole-home dehumidifier with an existing HVAC setup can help manage extreme moisture levels in humid climates.
A whole house dehumidifier works with the ac system to remove excess moisture when the air conditioning unit is not running enough. Variable-speed and two-stage systems also improve humidity control because they run longer, gentler cycles than older single-stage units. Homes with many occupants, finished basements, or persistent humidity problems often benefit from dedicated dehumidification.
High humidity affects more than comfort. It can damage indoor air quality, air quality, and the home itself. Sustained high indoor humidity can support mold growth, mildew in ductwork, musty odors, and allergy or asthma irritation. The EPA notes that moisture control is key to mold prevention.
Excess moisture can also warp hardwood floors, swell trim and cabinets, and create paint or drywall problems, especially in Metro Atlanta homes built before 2010. When an ac system struggles to remove humidity, homeowners often lower the thermostat, which increases energy use during Georgia’s long cooling season. A digital hygrometer plus Ragsdale’s Complete Comfort Maintenance can help keep humidity levels under control.
Ragsdale Heating, Air, Plumbing & Electrical is a local, full-service home comfort contractor serving Dallas, Loganville, and greater Metro Atlanta. We handle HVAC repair, new installations, insulation, indoor air quality, plumbing, electrical work, and humidity control.
Homeowners choose Ragsdale for 24-hour customer service, financing options, a 100% satisfaction guarantee, and 15-year parts and labor warranties on qualifying systems. Our Complete Comfort Maintenance membership includes routine tune-ups to keep air conditioning systems clean, efficient, and ready for Georgia humidity. If your ac system is not removing humidity like it should, contact Ragsdale for an in-home evaluation.
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