Can Air Conditioners Reduce Humidity? What You Need to Know

Managing indoor humidity is crucial for maintaining a comfortable and healthy living space. High humidity levels can make your home feel stuffy, lead to mould growth, and even worsen allergies.

But did you know your air conditioner might be doing more than just keeping you cool? Many people wonder if air conditioners can also help reduce humidity.

The short answer is yes − but there’s more to it than that. While air conditioners naturally remove some moisture from the air as part of the cooling process, their effectiveness depends on various factors like the type of unit, its size, and your home’s climate.

In this blog, we’ll explore how air conditioners handle humidity, when they might need some extra help and how to optimise your system for better moisture control.

How Do Air Conditioners Work?

Air conditioners do more than just cool your home − they also play a role in managing indoor humidity. But to understand how, it helps to know the basics of how these systems work.

At the heart of an air conditioner is a refrigerant, a special fluid that absorbs heat from your indoor air. This process begins when warm air is pulled into the unit and passes over cold evaporator coils.As the air cools, its ability to hold moisture decreases, causing water vapor to condense. This condensed water collects in a pan and is drained outside, effectively removing some humidity from your home.

The cooled, dehumidified air is then circulated back into your living space, leaving you feeling more comfortable. However, the extent to which an air conditioner can reduce humidity depends on its size, efficiency, and how long it runs.

While all air conditioners remove some moisture as a byproduct of cooling, they are not specifically designed to tackle excessive humidity levels like a dehumidifier.

Can Standard Air Conditioners Reduce Humidity?

Yes, standard air conditioners can reduce humidity, but their effectiveness depends on several factors. Here’s how they help and where they might fall short:

• Natural moisture removal: As part of the cooling process, air conditioners remove heat and moisture from the air. When warm air passes over the evaporator coils, water vapor condenses into liquid and is drained away, lowering humidity levels.
• Not designed specifically for dehumidification: While they do reduce some humidity as a by-product of cooling, standard air conditioners are not specialised dehumidifiers. They may struggle to handle excessively high humidity levels.
• Climate matters: In hot, dry climates, standard air conditioners work efficiently because there’s less moisture in the air. In humid environments, they may need help to maintain comfort.
• Unit sizing and run time: An air conditioner that is too large for your space cools quickly but doesn’t run long enough to remove significant humidity. A correctly sized unit works more effectively.

If humidity is a persistent problem, you may need additional solutions, like a dehumidifier or an air conditioner with enhanced moisture control features.

Features That Enhance Humidity Control

Not all air conditioners are created equal when it comes to managing humidity. Some units come equipped with features specifically designed to enhance moisture removal, making your home more comfortable even on sticky, humid days.

One key feature is a dehumidification mode, found in many modern air conditioners. This setting slows down the fan speed, allowing the unit to extract more moisture from the air as it cools.

Another helpful feature is adjustable fan speeds, which give you control over airflow. Slower speeds allow the air to stay in contact with the evaporator coil longer, improving moisture removal.

Proper unit sizing is another crucial factor. An oversized air conditioner may cool the room too quickly without running long enough to reduce humidity effectively. A properly sized unit strikes the right balance between cooling and dehumidifying.

Some advanced models also include humidity sensors, which monitor and adjust the indoor humidity level automatically. If you live in a particularly humid climate, investing in an air conditioner with these features can make a noticeable difference in your home’s comfort and air quality.

Dehumidifiers vs Air Conditioners

While air conditioners and dehumidifiers can both reduce humidity, they serve different purposes and work in distinct ways.

Here’s how they compare:

• Primary function:
  • Air conditioners: Designed to cool the air by removing heat and some moisture as part of the process. Cooling is their main goal, with humidity control being a secondary benefit.
  • Dehumidifiers: Specifically built to remove excess moisture from the air, making them ideal for managing high humidity levels without changing the air temperature significantly.
• Moisture removal efficiency:
  • Air conditioners: Remove a moderate amount of moisture but may struggle in areas with extreme humidity.
  • Dehumidifiers: Highly effective at extracting moisture, often equipped with a tank to collect the water for easy disposal.
• Energy usage:
  • Air conditioners: Consume more energy as they cool and dehumidify simultaneously.
  • Dehumidifiers: Generally use less energy since they focus only on reducing moisture.
• Best use cases:
  • Air conditioners: Ideal for spaces that need cooling and moderate humidity control.
  • Dehumidifiers: Perfect for damp basements, bathrooms, or humid climates where moisture is the primary concern.

For optimal comfort, some homes benefit from using both devices together.

Signs Your AC May Not Be Managing Humidity Well

If your home still feels sticky or damp even when the air conditioner is running, it might not be effectively managing humidity. Here are some telltale signs to watch for:

• Persistent damp or musty smells: A musty odor in your home often indicates excess humidity, which can lead to mould and mildew growth.
• Foggy windows: Condensation on windows is a clear sign that moisture levels are too high, and your air conditioner isn’t removing enough humidity.
• Sticky or clammy indoor air: If the air feels uncomfortably sticky despite cooling, the unit might not be running long enough to dehumidify effectively.
• Visible mould or mildew: Spots of mould on walls, ceilings, or vents suggest high humidity levels, which your air conditioner isn’t addressing.
• Excess water around the unit: Pooling water near the indoor unit could mean the drainage system is clogged or overwhelmed by excess moisture.

If you notice any of these signs, it may be time for AC maintenance, unit resizing, system repairs or additional humidity control solutions like a dehumidifier.

Tips to Optimise Humidity Control with Your AC

If your air conditioner isn’t effectively managing humidity, a few simple adjustments can make a big difference.

Here’s how to get the most out of your unit:

• Keep your filters clean: Dirty filters restrict airflow, reducing your air conditioner’s ability to dehumidify effectively. Clean or replace them regularly for optimal performance.
• Set the right temperature: Avoid setting the temperature too low. A moderate, consistent setting allows the unit to run longer and remove more moisture from the air.
• Use dehumidification mode: If your air conditioner has a dehumidification setting, use it to slow fan speeds and extract more moisture from the air.
• Seal your home properly: Gaps around doors, windows, or vents allow humid air to enter. Proper sealing and insulation help maintain lower indoor humidity.
• Schedule regular maintenance: Ensure the coils, drain lines, and other components are cleaned and functioning correctly to prevent issues like water pooling or reduced efficiency.
• Pair with a dehumidifier: For extremely humid environments, consider using a standalone dehumidifier alongside your air conditioner for added moisture control.

These tips can help improve comfort and reduce humidity-related problems in your home.

Stay Cool and Dry During Summer

Air conditioners can indeed help reduce humidity, making your home more comfortable and improving indoor air quality. While they aren’t designed to be full-time dehumidifiers, they naturally remove moisture as they cool the air.

To optimise humidity control, ensure your unit is the right size, well-maintained, and used effectively with features like dehumidification mode. For homes in highly humid climates or with persistent moisture issues, pairing your air conditioner with a dedicated dehumidifier can provide the perfect balance.

By understanding how your air conditioner handles humidity, you can create a cooler, drier and healthier living environment year-round.

Please note: This information is provided for advice purposes only. Regulations differ from state to state, so please consult your local authorities or an industry professional before proceeding with any work. See our Terms & Conditions here.