How Does Humidity Affect HVAC?

Hot weather naturally puts more demands on your HVAC system. But you may not know how humidity can impact both your heating and cooling units, not to mention your ducts. When you’re roasting or freezing, turning your HVAC off isn’t a preferable option. But how can you keep your system in the best condition possible? You may be surprised to find out just how much humidity is too much—and how it can reduce heating and cooling efficiency inside your home. Keep reading to learn what you need to know about HVAC maintenance during excess humidity.


Humidity in Hawaii


If you’ve lived in the Aloha State for long, you know how sticky and muggy it can get. Humidity levels vary across the state and by the season. Honolulu registers about 63% average humidity, but keep in mind that it can fluctuate throughout the day. If you live in Kailua, you can expect the average level to be around 68%. Like other parts of our state, Mililani’s outdoor humidity levels can get much worse in the winter—it frequently tops 80% in December.


The Science Behind Humidity


What causes the level of humidity to rise and fall? Water vapor is usually present in our atmosphere. When scientists talk about water vapor levels, they might use the term “relative humidity,” which compares how much moisture is in the air versus how much water vapor the air can actually hold. For instance, when a humidity reading is 75%, that means the air moisture level is at about three-fourths of the air’s total capacity.


Humidity in Warmer Climates


Air temperature has a large impact on how much water vapor the atmosphere can hold. As the outdoor temperature increases, the air is capable of holding more moisture. If the actual moisture level remains the same but the outdoor temperature rises, the humidity reading will drop—perhaps lowering to 70%, depending on how hot it gets. But here’s the catch: water evaporates faster in heat. With the Hawaiian Islands surrounded by the Pacific Ocean, there’s a seemingly endless supply of water. And that makes humidity conditions worse.


Humidity and HVAC


As you may have guessed, all that extreme humidity and excess moisture can do a number on air conditioners. Excessive humidity indoors eventually has a major impact. It can make air conditioning systems work harder thanks to the increased water vapor they must remove. This, of course, can affect the equipment’s performance: It doesn’t offer sufficient cooling capacity. You’ll know that you have a humidity issue in your home by some common symptoms in your air conditioning system:


  • Moist and clammy air
  • Foggy windows
  • Unpleasant musty smell

Poor Humidity Control and Air Conditioners


Besides musty odors and fogged-up windows, you may also experience clammy skin. Logically, comfort levels decrease with all these nasty effects. But there’s another problem that excessive humidity can cause: higher energy bills. Poor humidity control decreases air conditioning effectiveness, not just because it has to take water out of the air. You also don’t feel as cool, so you lower your A/C’s temperature setting. You end up paying more money thanks to the excess moisture content in the air.


Humidity Control and HVAC Ducts


Inside your HVAC ducts, your indoor humidity issue is wreaking havoc, making an ideal climate for mold. Because the outdoor temperature skews a bit lower, you might not even think about A/C or the mold possibly growing, during the winter season. But all it takes is inconsistent humidity control to give both mold and algae the right conditions to grow and take-over your home’s ductwork, which can lead to allergic reactions plus upper respiratory problems.


The Role Moisture Plays in Home Heating


The effects of poor humidity control are not limited to air conditioning units; humidity levels can drop indoors during the winter, making the inside air seem drier. And just like high humidity can make the air feel warmer, low humidity can cause us to feel cooler. So, you turn up the heat—and your heat pump or furnace is forced to work harder. And, of course, your utility bills increase. That’s not ideal in any season.


Solutions for Home Humidity Control


As the outdoor temperature goes up or down, you want to maintain an ideal humidity level inside your home. Thankfully, you have some options to help you accomplish this goal. Some people purchase small appliances for better humidity control, namely humidifiers and dehumidifiers. But did you know that these devices can be installed right in your HVAC system? Dehumidifiers eliminate moisture from the air before it’s channeled through your ductwork. On the flip side, an integrated humidifier can add moisture to the air.


Both humidifiers and dehumidifiers can help maintain proper humidity levels inside your home. Your home’s safe level for humidity can vary, but most experts suggest keeping it between 40% and 60%. Together, they can rectify any existing humidity issue indoors. Paired with powerful air conditioners and heating systems, they can help keep your space comfortable and address humidity control problems.


HVAC and Ductwork Maintenance


Once you’ve solved the humidity-control issue inside your home, it’s a good idea to have your air ducts checked and cleaned. Duct cleaning can eliminate any moisture buildup, along with mold, algae, and other debris. Aside from humidity monitors and other regular HVAC maintenance, having your AC ducts cleaned should mitigate any air quality issues inside your home.


Your Hawaiian Indoor Comfort Experts


Outdoor humidity levels are one thing. But you must also pay attention to indoor humidity levels and their effects on furnaces and air conditioners. Both high and low humidity can impact HVAC efficiency and even ruin the equipment if not corrected. Consistent humidity control is key to keeping your heating and air conditioning equipment in the best shape possible through the hot summer months and winter.


Proper duct maintenance is also important in keeping homes comfortable in any season. The same symptoms that indicate humidity issues affecting an air conditioning unit can also point to problems in your ductwork. Other signs include excess dust plus visible mold or mildew around air registers. The buildup of debris in your ducts can also manifest as uneven airflow—in other words, better air circulation in some areas than others.


For over 20 years, Hawaii Indoor Air Specialists has made indoor living safer for both residential and commercial clients. Based in Mililani, HIAS offers dryer vent and air duct cleaning. Our highly-trained and certified technicians perform high-quality work that meets safety compliance requirements and our own strict standards. Get a quote for duct cleaning through our convenient online form or call us at <a ” href=”tel:8066264774″>(806) 626-4774


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