You hear the air conditioner running. The thermostat says the house is cool. But instead of feeling comfortable, the air inside your Rowlett home feels sticky, damp or clammy.
Your air conditioner doesn’t just cool your home. It also plays an important role in controlling indoor humidity. As warm indoor air passes across the cold evaporator coil, moisture condenses out of the air and drains away. When that process isn’t working effectively, your home can reach the thermostat setting while still feeling uncomfortably humid. During a hot and humid North Texas summer, several HVAC problems can contribute to excessive indoor humidity.
What Should Indoor Humidity Be During the Summer?
For most homes, keeping indoor relative humidity somewhere around 40% to 60% generally provides a reasonable balance of comfort and moisture control, although the ideal level can vary depending on the home and outdoor conditions.
Once indoor humidity regularly climbs above approximately 60%, you may begin noticing problems such as:
- Sticky or clammy indoor air
- Musty odors
- Condensation on windows or vents
- Rooms that feel warmer than the thermostat indicates
- Increased potential for mold or mildew
- Difficulty getting comfortable without lowering the thermostat
If your home feels humid even while the AC is operating, the HVAC system is one of the first places to investigate.
Why Does an Air Conditioner Remove Humidity?
An air conditioner cools your home by moving indoor air across a cold evaporator coil.
As that air cools, moisture condenses on the coil much like water droplets form on the outside of a cold glass on a summer day.
That water collects in a drain pan and leaves the home through the condensate drain.
The process takes time.
That’s important because some humidity problems aren’t caused by an AC that doesn’t run enough. They’re caused by an air conditioner that cools the home too quickly.
An Oversized AC Can Make Your House Humid
Bigger isn’t always better when it comes to air conditioning. An oversized air conditioner can rapidly lower the indoor temperature and satisfy the thermostat before it has operated long enough to remove sufficient moisture from the air. The system shuts off. A short time later, it turns on again.
This pattern of short cooling cycles may keep the thermostat at the desired temperature while leaving indoor humidity higher than you’d like.
That’s one reason proper HVAC sizing is so important when replacing an air conditioning system.
The goal isn’t simply to install an AC powerful enough to cool the house. The equipment needs to be appropriately sized for the home’s actual cooling load.
Short Cycling Can Reduce Humidity Control
An oversized system isn’t the only reason an AC might run in short bursts.
Thermostat problems, dirty components, airflow issues and mechanical problems can also contribute to frequent cycling.
If your air conditioner repeatedly starts and stops after very short periods, it may not have enough operating time to effectively remove moisture.
Frequent short cycling can also increase wear on HVAC components.
Dirty Air Filters and Airflow Problems
Proper airflow is essential for both cooling and humidity control.
A dirty air filter can restrict the amount of air moving through your HVAC system. Problems with the blower, evaporator coil, ductwork or return-air system can also interfere with airflow.
If you’re experiencing unusually high humidity, checking the air filter is a good first step.
If the filter looks heavily loaded with dust and debris, replace it with the appropriate filter for your system.
If humidity problems continue, the system may need professional inspection.
Your Evaporator Coil May Be Dirty
The evaporator coil is where both cooling and moisture removal occur.
Dust and debris accumulating on the coil can interfere with heat transfer and reduce HVAC performance.
Because the evaporator coil is located inside the HVAC system, cleaning it usually isn’t a DIY maintenance project.
A technician can inspect the coil and determine whether buildup is contributing to cooling or humidity problems.
Check the Condensate Drain
Remember all that moisture your AC removes?
It has to go somewhere.
Condensation collected by the HVAC system normally flows through a condensate drain line. If the drain becomes clogged, water may back up around the system.
Depending on the HVAC installation, a clogged drain can cause water leaks, shut down the AC or contribute to moisture problems around the equipment.
Water around your indoor HVAC unit should never be ignored.
Duct Leaks Can Bring Humid Air Into the System
Many Rowlett-area homes have ductwork running through attics and other unconditioned spaces.
If return ductwork leaks, the HVAC system can pull hot, humid attic air into the system.
Supply-side leaks create another problem by allowing cooled and dehumidified air to escape before reaching your living spaces.
Both situations make it harder to maintain comfortable indoor conditions.
Air Leaks Around Your Home Matter Too
Your HVAC equipment isn’t always the sole cause of excessive humidity.
Outdoor air can enter through gaps around windows and doors, poorly sealed attic penetrations and other openings in the home’s building envelope.
Every bit of humid outdoor air entering the house adds moisture your air conditioner must remove.
Improving air sealing and insulation can sometimes reduce both humidity and cooling costs.
Why a Humid House Feels Hotter
High humidity makes it harder for perspiration to evaporate from your skin.
That’s why a 75°F room with high humidity can feel much less comfortable than another room at exactly the same temperature with better humidity control.
Homeowners sometimes respond by lowering the thermostat several degrees.
That may make the house colder, but it doesn’t necessarily solve the moisture problem and can increase energy consumption.
Addressing the source of excessive humidity is usually the better solution.
Would a Whole-Home Dehumidifier Help?
Sometimes.
If your HVAC system is operating properly but your home still struggles with excessive humidity, a whole-home dehumidifier may provide additional moisture control.
Unlike portable dehumidifiers designed for individual rooms, a properly installed whole-home system can work with your HVAC system to manage humidity throughout much or all of the house.
However, it’s important to identify the cause of the humidity problem before adding equipment.
There’s little reason to install a dehumidifier to compensate for a malfunctioning AC system, serious duct leakage or another repairable problem.
Signs It’s Time to Have Your HVAC System Checked
Consider scheduling HVAC service if you notice:
- Indoor humidity consistently above roughly 60%
- A sticky or clammy feeling throughout the house
- Musty odors
- Condensation around vents or windows
- Water near your indoor HVAC equipment
- Very short AC cycles
- Weak airflow
- Uneven temperatures
- Increasing cooling bills
- An AC that isn’t keeping the home comfortable
A professional inspection can help determine whether the issue involves your air conditioner, ductwork, drainage, equipment sizing or another source of excess moisture.
Improve Indoor Comfort in Your Rowlett Home
A comfortable home isn’t just about the number displayed on your thermostat.
Temperature, airflow and humidity all work together to determine how comfortable your home actually feels.
If your Rowlett home feels sticky or humid even though the air conditioner is running, Barnaby Heating & Air can help identify what’s causing the problem.
We’ll evaluate your HVAC system and help determine the right solution, whether that’s maintenance, repair, airflow improvements, humidity control or another recommendation.
Contact Barnaby Heating & Air today to schedule HVAC service and enjoy a cooler, more comfortable North Texas home this summer.
