Why Does My Oregon Coast Home Feel Humid Even When the AC Runs?

If your home feels humid with the AC on, a few different issues could be going on. While this may not be something you need to worry about, it could also indicate a problem. In Bandon, our marine layer means heating, ventilation, and air conditioning (HVAC) systems have more humidity to contend with. To see how you can reduce your home’s relative humidity (RH), reach out to Alpha Heating & Air for an indoor air quality (IAQ) evaluation.

Why Cooling and Dehumidification Are Connected

On the Oregon Coast, humidity and AC concerns are common. An AC or heat pump is only designed to remove humidity while it is running. Air moves past the coil, allowing water to condense on the coil. If the unit isn’t on, this process cannot happen.

Why Bandon Homes Feel Damp Even in Mild Weather

Bandon homes can feel damp in mild weather because of our marine-layer humidity. Our coastal fog, cool evenings, and crawlspace moisture make this problem worse. Plus, our relatively mild weather means that the cooling cycles don’t run long enough to reduce Bandon home humidity. We often see coastal homes that feel clammy because they reach the appropriate temperature before the humidity level has fallen enough.

Common Reasons Your AC Is Not Removing Enough Humidity

There are a few common reasons why a home feels humid with AC running. If you need assistance with diagnosing your AC or heat pump problem, our team can help.

The System Is Oversized

When an AC is installed, an HVAC technician uses a Manual J load calculation to determine the appropriate size for your square footage, the number of windows, insulation levels, the number of occupants, and other factors. If the system is too large for your needs, it will reach the right temperature and shut off too quickly.

Because of this, you’ll have issues with the AC not removing humidity from the air. With shorter cycles, there just isn’t enough time to remove as much moisture.

Airflow Is Too High or Poorly Balanced

In this situation, air flows across the evaporator coil too quickly. Because there isn’t enough time to remove moisture, your humidity levels will feel uncomfortable. The right solution depends on the cause. For example, we may need to adjust your blower fan speed or fix your ductwork.

The Coil or Filter Is Dirty

Dirty filters and coils are common reasons why homeowners experience Oregon Coast humidity with an AC on. Once these components become dirty, it restricts airflow, increasing the likelihood that the evaporator coil freezes. When this occurs, the coil will struggle to remove any moisture from the air. You’ll also likely notice warmer air coming from your vents.

The Thermostat Settings Are Not Helping

Before you call for AC repairs, you should check your thermostat settings. The fan should be set to “Auto” mode and not “On” mode. If you have it in “On” mode, the fan will run constantly. This can actually increase the humidity levels because the moisture that was collected on your coils gets blown back into your home.

If you have a central humidifier or portable humidifier, don’t forget to check your humidity settings. Family members sometimes adjust settings without telling anyone, leading to uncomfortable humidity levels.

The Home Has Moisture Coming From Ducts, Crawlspaces, or Ventilation

Another common problem we see is leaky ducts. If you have duct leaks, moisture from your crawlspaces can get pulled into the ductwork and end up in your home. You may also notice sweaty ducts, high RH, and uneven room temperatures if the duct insulation is damaged or inadequate.

When the Issue Is More Than Comfort

Dealing with Oregon Coast humidity and AC problems isn’t just a comfort issue. These issues can also impact your family’s health and result in damage to your home. For example, the moisture from sweaty vents can cause warped wood and microbial growth. You should always reach out for an HVAC inspection if you notice sweating vents, window condensation, poor air quality, or musty odors.

Safe Checks Homeowners Can Make First

Homeowners can use the following steps to address coastal HVAC humidity on their own. If these techniques don’t work, it’s time to reach out to our team for professional support.

1. Check the Filter: Replace dirty air filters. Ideally, filter replacements should occur at least every 30 to 90 days, depending on the manufacturer.
2. Note Indoor Humidity Patterns: These patterns can help your HVAC technician determine the underlying cause of your AC or heat pump’s humidity problem.
3. Check the Thermostat Settings: Verify that your thermostat is set to the right temperature and the fan is in “Auto” mode.
4. Look for Visible Condensation: Visible condensation or puddling indicates different problems. Note where the condensation is occurring and when it is happening.
5. Record Which Rooms Feel Damp: Go from room to room to see if every room feels damp. Sometimes, there will be a ductwork or airflow issue that causes uneven air distribution.

How Alpha Diagnoses Coastal Humidity Problems

When our team comes out to check your home, we’ll perform the following diagnostic checks to determine the source of your problem.

• Airflow: We’ll first check your airflow to ensure air moves across the evaporator coil slowly enough to remove moisture.
• Coil Inspection: Our team will inspect the evaporator coil and clean it as needed.
• Duct Review: We will inspect your ducts for leaks and damage.
• Thermostat Settings: Our HVAC technicians will verify that your thermostat is set to the correct temperature and mode.
• Equipment Sizing: We will analyze your system, recent changes to your home, household occupancy, and other factors to determine if you have the appropriate equipment size.
• IAQ Evaluation: If no issues are causing the high RH, we may recommend a dehumidifier for your Oregon Coast home.

Schedule Coastal Comfort Service in Bandon

If your home feels humid even with the AC on, there may be a problem with your HVAC system. Our trusted local technicians can evaluate your RH, comfort levels, and system performance. Then, we can quickly fix the problem through our same-day services.

Reach out to get an IAQ evaluation for your home.