Humidity is more than a comfort issue; it can affect your health, energy bills, and even the structure of your home. Many homeowners ask how to reduce humidity in house with AC because when indoor humidity levels climb above 60%, musty odors, condensation on windows, and mold growth in hidden corners become common problems. For families in Brookfield, Danbury, and across Connecticut, hot summers often bring sticky air that makes it harder for an air conditioner to keep up.
While air conditioners are designed to cool air and remove some moisture, there are times when they struggle. In this guide, you’ll learn how AC systems reduce humidity, practical steps to improve dehumidification, and when to bring in a professional.
Why Humidity Control Matters for Home Comfort
Humidity refers to the amount of water vapor in the air. While some moisture is healthy, too much can make your house feel warmer than it really is. High humidity levels cause sweat to evaporate more slowly, leaving you feeling sticky even at a comfortable temperature.
Experts, including the EPA, recommend keeping indoor humidity between 30% and 50%. Above this range, you run the risk of:
- Mold growth and mildew can damage drywall, insulation, and wood.
- Dust mites and allergens that thrive in damp environments can worsen asthma or allergies.
- Structural damage such as warped wood, peeling paint, and rot.
- Higher cooling costs, as your AC works harder to achieve the same comfort.
When your air conditioner is actively cooling, it should be removing both heat and moisture. But if you still notice excessive humidity indoors, your system may need adjustments or maintenance.
How an Air Conditioner Reduces Humidity
To understand why your AC sometimes struggles, it helps to know how the process works.
An air conditioner cools your home by pulling in warm, humid air and passing it over the evaporator coil, which is kept cold by refrigerant. As the air cools, water vapor condenses on the coil and drains away through the condensate pan. This process removes both sensible heat (temperature reduction) and latent heat (moisture removal).
However, several issues can prevent your system from reducing humidity effectively:
- Oversized AC units cool the air too quickly and don’t run long enough to remove moisture.
- Dirty filters or coils impede airflow and prevent condensation from occurring.
- Incorrect fan speeds push air through the system too fast, reducing dehumidification.
- Low refrigerant charge reduces the coil’s ability to cool air and extract moisture.
Simply put, an air conditioner does reduce humidity, but only if it’s properly maintained and sized for your home.
Steps to Reduce Humidity in a House with AC
While some fixes require a licensed HVAC professional, homeowners can take several steps to improve their air conditioner’s ability to manage humidity.
Clean or Replace Air Filters Regularly
Air filters play a vital role in airflow. When filters become clogged with dust and debris, the system struggles to move air across the coils, which lowers efficiency and dehumidification. Replacing filters every 1–3 months is one of the easiest ways to reduce indoor humidity and protect your AC unit.
Keep Evaporator and Condenser Coils Clean
Dirty coils block heat and moisture transfer. When dust coats the coils, condensation cannot form effectively, and excess humidity lingers in your home. A professional cleaning once a year, before the cooling season, helps maintain both cooling and dehumidifying performance.
Adjust the Fan Speed
Most AC systems allow technicians to adjust blower fan speed. Slower speeds mean air spends more time on the cold coils, allowing more moisture to condense. This adjustment is highly effective in humid climates but should be done by a trained HVAC professional to avoid frozen coils or compressor strain.
Check Refrigerant Levels
Low refrigerant reduces your system’s ability to cool air and remove humidity. If your AC isn’t dehumidifying, a refrigerant leak could be to blame. Only certified technicians should check and recharge refrigerant, as handling it requires specialized training.
Install or Upgrade to a TXV (Thermal Expansion Valve)
A thermal expansion valve improves refrigerant flow to the evaporator coil, helping the system adapt to varying loads and humidity levels. If your system is older or struggles with dehumidification, adding a TXV can make a significant difference in efficiency and comfort.
AC vs Dehumidifier: Which Is Better?
Air conditioners are designed primarily to cool, not dehumidify. In some situations, adding a dehumidifier is the best way to achieve balanced indoor humidity.
Here’s how AC compares to other options:
| Method | Pros | Best For |
|---|---|---|
| AC Adjustments | Energy-efficient, uses existing system | Moderate humidity issues |
| Portable Dehumidifier | Affordable, targets problem rooms | Basements, bedrooms, single spaces |
| Whole-House Dehumidifier | Integrated with HVAC, consistent results | Persistent, high humidity across the home |
For homes in Connecticut where summers bring sustained high humidity, a whole-house dehumidifier is often the most reliable solution. It works with your central AC to remove excess moisture, improve comfort, and prevent mold growth throughout the house.
Professional Solutions for Persistent Humidity
Sometimes, no matter how many DIY steps you take, humidity remains a problem. That’s when professional expertise matters.
An HVAC professional can:
- Clean and service evaporator and condenser coils.
- Adjust blower fan speeds to optimize dehumidification.
- Test and recharge refrigerant levels.
- Install a TXV or whole-house dehumidifier.
- Diagnose issues like compressor failure, blocked condensate drains, or system oversizing.
At Keep Cool Heating & Cooling, we often see homeowners running their AC longer than necessary because humidity makes the air feel warmer. Professional service not only restores comfort but also reduces energy consumption by making your AC more efficient.
Conclusion
Humidity control is a vital part of indoor comfort and energy efficiency. By learning how to reduce humidity in the house with AC, you can improve air quality, protect your home from mold and structural damage, and lower energy bills. Simple steps like replacing filters, keeping coils clean, and ensuring your AC is serviced annually can go a long way. For stubborn humidity issues, a whole-house dehumidifier or professional HVAC adjustments may be the solution.
For homeowners in Brookfield, Danbury, and surrounding Connecticut towns, Keep Cool Heating & Cooling delivers expert HVAC services to keep your home comfortable year-round. Contact us today to schedule an inspection or learn more about dehumidifier installation.
FAQs
How to lower the humidity in the house using the AC?
To lower humidity, keep air filters and coils clean, set fan speed correctly, and ensure refrigerant levels are adequate. If your AC still struggles, adding a dehumidifier can improve performance.
Which mode is best for AC in humidity?
Using the “cool mode” with auto fan settings is best for reducing humidity. Avoid “fan only” mode, as it circulates humid air without removing moisture.
Why is my house always 70% humidity?
If indoor humidity stays around 70%, your AC may be oversized, poorly maintained, or leaking refrigerant. This level is too high for comfort and mold prevention. A professional evaluation is recommended.
Why is my AC not removing humidity?
Common causes include dirty coils, clogged filters, incorrect fan speed, or refrigerant problems. Oversized systems that cool too quickly also fail to remove enough moisture.
