Can You Lower Humidity by Running the Air Conditioner?

Unwanted humidity can result in many problems, like mold and mildew, musty rooms, structural problems, and an uncomfortable muggy feeling. That’s why it’s necessary to control humidity if you plan to improve indoor air quality and home comfort. 

The perfect relative humidity level is about 30 to 50 percent. Summer is usually the toughest time of year to remain within this range. Fortunately, running the air conditioner can help. 

After all, air conditioning doesn’t only cool your home—it also decreases humidity. Here’s a look at how this works, along with recommendations to control indoor humidity levels. 

How Air Conditioning Lowers Humidity 

Contrary to popular belief, your air conditioner doesn’t put in cool, dry air in your home—it removes heat and humidity. The process involves refrigerant, which absorbs heat and moisture effectively from the indoor air. Here’s what happens: 

  • Indoor air flows through the ductwork and passes over the evaporator coil filled with cold refrigerant. 
  • The refrigerant stores heat, and the moisture in the air accumulates on the coil. 
  • The condensation falls into the condensate pan below the evaporator coil and drains away. 
  • Cooler, dehumidified air blows back into your home. 

Tips to Reduce Humidity 

Using the air conditioner might be enough to bring the relative humidity under 50 percent in dry climates. But if high humidity remains a problem in your home, consider these tips. 

Ventilate Correctly 

Turn on the exhaust fan in the bathroom, kitchen and laundry room when you shower, cook and wash clothes. Detached ventilation removes humidity at the source to keep these rooms cool. You can also open a window when it’s comfortable outside to draw in fresh air. 

Clean Up Standing Water 

Water on shower tiles, kitchen counters and laundry room floors elevate indoor humidity and will sometimes stimulate mold growth. Wipe up standing water promptly to protect against these problems. 

Use a Dehumidifier 

If you struggle with increased humidity in the summer, look into installing a whole-house dehumidifier that operates in tandem with your air conditioner to make every room more comfortable. A whole-house unit can even function independently of the AC to eliminate humidity on more temperate days without running the air conditioner. This technique saves you money and doesn’t leave you with that “cool but clammy” feeling. 

Flip the AC Fan to Auto 

The condensation that collects on the evaporator coil needs time to build up and flow away. If you are running the air conditioning fan continually, the moisture won’t be able to leave your home. That’s why it’s more efficient to adjust the fan to “auto” so it only runs when the AC compressor switches on. You should be able to change this setting easily on your thermostat. 

Change the Air Filter Regularly 

An obstructed air filter traps dust and debris and can encourage mold and mildew if it gets wet. This adds more moisture and mold spores into your home each time the AC turns on. Exchange the air filter every month or as advised by the manufacturer to lower indoor humidity and increase air quality. 

Adjust the Fan Speed 

Optimizing the fan speed can be tricky. High airflow helps the AC meet your cooling demand on the hottest days, but this could cause shorter cycles that block effective dehumidification. Speak with an HVAC technician to help you select the right fan speed for your comfort preferences. 

Clean the Evaporator Coil 

A grimy coil can’t cool and dehumidify effectively. If your air conditioner is having trouble reaching the preferred temperature, get in touch with our HVAC specialists to tune up your cooling system and clean the evaporator coil. Cooling and dehumidifying efficiency should improve as a result. 

Confirm the Refrigerant Charge 

A depleted supply of refrigerant can impede your air conditioner’s ability to do its job. Left ignored, major issues like a frozen evaporator coil or compressor failure can occur. Only a qualified HVAC technician can resolve refrigerant leaks and replenish the system as needed, offering you another reason to request an AC tune-up. 

Exchange Your Air Conditioner 

If your home has continuous comfort trouble and your air conditioner is getting older, it could be time to replace it. Install a new AC system with modern features, like a thermal expansion valve (TXV) and variable blower motor. A TXV offers the precise amount of refrigerant consistent with the air temperature, and a variable blower motor adjusts the fan speed to satisfy demand. Both features increase cooling and dehumidifying efficiency. 

Manage Indoor Humidity with Stevenson Service Experts 

If you decide it’s time to install a whole-house dehumidifier or replace your air conditioning, Stevenson Service Experts can help. Our HVAC services are tailored to optimize home comfort and energy efficiency for your long-term satisfaction. To share questions or schedule a visit from one of our certified heating and cooling technicians, please give us a call today. 

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