My Air Conditioner is Working but My House Feels Humid

fan in room

A very frequent question we get asked in the air conditioning business, especially during the hot summer months is, “Why does my house feel so muggy?” This can be an extremely frustrating experience. Maybe your floors feel sticky or you begin to notice condensation developing in odd places. That thick and sticky feeling we call “muggy” is also commonly referred to as relative humidity. Basically, relative humidity measures the humidity in relation to the temperature.

Why is My Air Conditioned House Muggy?

Here’s why your home feels muggy even when your A/C seems to be working. We see this a lot in Nashville, Hendersonville, Brentwood, Franklin, Gallatin, and pretty much everywhere in the greater Nashville area during the hot summer months. It can be extremely irritating to feel uncomfortable in your own home when the humidity level is high, even with a working air conditioner unit. The simple answer to why your house feels humid is that hotter air holds more moisture than cooler air. However, once hot air begins to cool, it becomes even more muggy. Therefore, in most cases, this is likely caused by an excess amount of indoor humidity.  

Well, you’re probably wondering why there is so much humidity in your house. Here are a few of the reasons why your house feels so muggy. First, your air conditioning system may not be equipped to regulate indoor humidity. Oftentimes, we forget that air conditioning units are designed to do more than just cool your home. AC units are intended to improve indoor air quality. It’s important to understand that just because your HVAC unit is cooling your home, does not necessarily mean it’s working properly. 

One of the main reasons causing humidity in your home could be that your system is not dehumidifying the air as it is cooling it. A working AC system will both cool and dehumidify the air in your home. But even if the air conditioner seems to be doing its job properly, other factors can contribute to an excess amount of humidity in a home. Your house may feel muggy because you simply have too many people in your home. Too many warm bodies in a house can accumulate a decent amount of excess moisture through perspiration. Yes, sweat. 

Cooking might also contribute to that humid feeling in your home. All that evaporating water from your stovetop goes into the air, which is why most ovens have ventilation fans directly above them. In some cases, even bathing can create that muggy feeling, as moisture and steam fills the air in your bathroom and seeps throughout the rest of the home. Not to sound like a broken record, but this is why bathrooms also come standard with ventilation fans. 

Plus, let’s not forget that if it’s humid outside, it’s not uncommon for it to be humid inside! We’re no strangers to thunderstorms here in Nashville. Thunderstorms and heavy rain on a super hot day will create a ton of moisture in the air. The more moisture there is in the outdoor air, the more relative humidity will find its way into your home. Even if you keep all the windows and doors shut, your house may still experience increased humidity on a muggy day.

Your Air Conditioning Unit is Too Old

If your house feels humid, another possible reason could be that your HVAC unit is too old. Similar to other machines or in-home appliances, as AC units age, they experience wear-and-tear and will eventually begin to work less efficiently. If your AC unit is no longer removing humidity from the air, it may be time to consider getting a replacement. This is likely to happen more frequently if your AC system is not receiving regular maintenance. At this point, it is crucial to heavily consider whether the cost of getting your old AC system replaced outweighs the cost of investing in a new one.

How to Get Rid of Humidity in Your Home

Now that we’ve gone over a few reasons why your home is feeling muggy inside, here are some ways to combat excess moisture in the air:

Keep the AC Running

One of the most basic ways to dehumidify your home is to keep your air conditioning running at all times. We know that doesn’t sound very cost effective, but when your unit is not running, it’s not doing the job of dehumidifying your home. Imagine it’s raining outside and your AC is on Auto Mode. This means that it will turn off as the rain cools the house down. However, if it’s hot and humid outside, it will eventually make its way inside as well. While you may feel like the temperature inside is fine, it could still get quite muggy from the excess moisture in the air. 

If humidity is a recurring issue in your home, just try keeping your AC running all day on those muggy days. Although it may not be the most energy-efficient option, it helps.

Get a Proper Sized AC Unit

When it comes to air conditioning, size always matters. We don’t make the rules. An AC unit that is too small in relation to the square-footage of your home can cause seriously frustrating problems. Not only will it fail at cooling your home efficiently, but it will also fail at dehumidifying the air inside. An AC system that is too large for your home has a powerful compressor that will turn on and off frequently. Therefore, the system will never run long enough to properly remove humidity from the air. You should always make sure that your AC system is not too large or too small for your home. At FiveStar, we always recommended having an AC system installed with variable speed control to assist in offsetting humidity. We use a process called “load calculation” to figure out the proper sizing of an AC unit. Always be sure to consult with a professional and licensed HVAC technician who knows how to properly size your unit and perform the installation of a new system successfully.

Add a Dehumidifier to Your AC System

Sometimes even the best AC systems can’t control excess moisture during muggy weather. Not ready to buy a new HVAC unit yet? We get it. That’s why at FiveStar, we offer our clients the option of adding a dehumidifier to their AC system for better humidity regulation! Some newer air conditioners have really effective humidity controls for removing moisture in the air, but some don’t. If your system’s dehumidifier is not working like it should, consider getting a separate one that is compatible with your AC unit. A dehumidifier does exactly what it sounds like. It removes excess moisture from the air and regulates air quality as it flows through your ductwork. Call us FiveStar Plumbing, Heating and Cooling and ask about high efficiency dehumidifiers to accompany your HVAC system.

Get Your Ductwork Inspected

Sometimes air begins to leak from your ductwork which could lead to that sticky, muggy feeling in your home. It is a good idea to have your air ducts inspected for leaks regularly. The primary source of moisture in your home is often from the outdoor air leaking in through cracks or leaks in the ductwork. If your AC is cooling but your house feels humid, don’t ignore it! Our team would be happy to inspect your air ducts to ensure that they are working properly.