Low airflow in an A/C unit can cause benign—albeit annoying—issues like hot and cold air pockets in your Sterling, VA home. When left unchecked, however, it can result in more serious problems, like compressor failure. For those who want to avoid spending money on heating and air conditioning repair for avoidable breakdowns, education is key. Understanding the root causes behind airflow issues will better prepare you for troubleshooting, DIY repairs and future prevention. Let’s dive in! Need heating and ac repair in Northern Virginia? Give the team at Cardinal Plumbing, Heating and Air a call at (703) 645-4527 or visit us online to book services today.

The Symptoms of Low A/C Airflow

HVAC units suffering from low airflow tend to take on greater levels of wear and tear. Keep an eye out for the following signs:
  • No Air—weak or low A/C airflow can make it seem like no air comes out of your air vents when the unit runs.
  • Hot and Cold Pockets—one of the first indicators of airflow issues occurs when your unit is no longer able to cool your space evenly.  
  • Air Pressure Fluctuations—if you notice drafts or doors that slam by themselves, who you gonna call? Your local HVAC technician. That’s who. Air pressure fluctuations in the home are often a sign of airflow issues in your A/C unit. Move over, Ghostbusters! We’ve got this one under control.
  • Warm Air Blows Out—when your A/C unit has one job and it does the exact opposite instead, there’s trouble afoot. Keep your cool and investigate the common airflow problems we’ll discuss next.

The Risk of Low Airflow in Your A/C Unit

Low airflow impedes your A/C unit’s ability to cool your home efficiently. This means your unit needs to work harder to maintain desired temperatures, which raises utility costs and places unnecessary strain on your system. Frequent repairs, broken parts and—worst of all—compressor failure can all result from improper A/C airflow.

10 Causes for Low Airflow in AC Units

Despite the serious problems that low airflow can create, many of its root causes have simple fixes. These are the most common reasons for A/C airflow issues:

  • 1. Dirty or Clogged Air Filters

    A/C filters remove dust, dander, pollen and other contaminants from the air that enters your unit. This goes a long way toward improving indoor air quality and keeping pollutants out of your air ducts. When filters become clogged with the particles they trap, your unit will strain to pull air in. HVAC air filters need to be replaced (or cleaned, if reusable) every 30-90 days. The optimal frequency for your unit depends on factors like climate, lifestyle and the number of pets in the home. This is a simple fix that most homeowners can take care of themselves in between scheduled maintenance visits.

  • 2. Airflow Around Your Condenser Unit

    Most residential A/C units rely on an outdoor condenser unit to release warm air removed from the home to the outdoors. Condenser units can become obstructed by encroaching trees and shrubbery, or its fins can become clogged with debris like leaves or twigs. As a result, warm air has nowhere to go, and your entire system will suffer. To avoid airflow problems around your condenser unit, inspect it frequently and remove any debris that gets in the way. Be sure to trim back nearby branches and bushes, leaving a 2-ft clearance around the unit.

  • 3. Clogged or Leaking Air Ducts

    The air ducts in your home transport cooled air from your system to your air vents. A build-up of dust, mold growth or insect and rodent infestations can create clogs inside of your air vents, blocking air flow. Another potential air duct issue occurs when air ducts aren’t insulated or sealed properly. This leads to air leaks, which means cooled air might escape into unused areas, like the attic. Have a professional inspect and clean your air ducts or seal them if necessary.

  • 4. Low Refrigerant Levels

    Low refrigerant levels are a common cause for airflow issues coupled with reduced cooling efficiency. Refrigerant levels should, ideally, remain consistent. Low levels indicate a unit that was undercharged to begin with or a system leak. A slow refrigerant leak will cause a gradual decline in cooling over time. Have your local Sterling HVAC professional test for leaks and repair them right away.

  • 5. Dirty Coils

    The condenser coil in your air conditioner releases the warm air that’s removed from your home. As this part is housed in your outdoor condenser unit, it can become covered in dirt and grime that prevents it from releasing heat. This means your unit has to work harder to cool your space, all while running hot. Clean coils one or twice a year to avoid airflow issues and the risk of your unit overheating.

  • 6. An Oversized HVAC Unit

    A unit that’s too big for the space it’s in will reach your desired temperature setting quickly and shut off before completing a full cooling cycle. This is called “short cycling.” Though it may seem like a good thing, it really means your unit perpetually runs in its start-up phase. This requires more energy, and rather than cooling your space evenly, temperatures will fluctuate often. Short cycling also means your unit never runs long enough to remove humidity from your home, which is an important function of your cooling system.

  • 7. A Faulty Thermostat

    A faulty thermostat, one with low batteries, or one that’s placed in an area prone to temperature fluctuations, such as near vents or in direct sunlight, can cause airflow issues. This is often a good place to begin troubleshooting, as repairs are simple and inexpensive.

  • 8. A Lack of Power

    Problems with the power source that runs your unit’s fan can cause inefficient airflow as the fan struggles to circulate air. This issue can point to electrical problems like frayed wires, or it can indicate issues with the fan motor, fan belt or fan blades. It’s best to have a qualified HVAC technician take a look.

  • 9. Dirty Fans

    Blower fans move air through your air ducts. When these fans become covered in dirt or grime, it can slow them down, causing weak air flow. Be sure to inspect and clean fans on a regular basis.

  • 10. An Aging Unit

    HVAC units last 12–15 years on average (or up to 20 years with regular maintenance). If you notice decreased cooling efficiency and air flow issues over time and your unit is older than 15 years, it’s probably time for an upgrade. Rather than shelling out for constant heating and air conditioning repair, get in touch with a professional to see what’s available.

Get the Best Heating and AC Repair in Sterling, VA

The best way to prevent air flow issues in your home is to invest in annual maintenance by a licensed professional. The pros at Cardinal Plumbing, Heating and Air can help solve air flow issues and keep your unit in ship shape year-round. Call (703) 645-4527 today or visit us online to learn more about our heating and air conditioning repair services.