What to Know About AirflowWithout adequate system airflow, the comfort level in your home—as well as heating/cooling costs and even indoor air quality—are compromised.

Your HVAC system is carefully designed to produce and distribute a specific volume of conditioned air to match the unique heating and cooling requirements of your home. Without proper airflow, many system functions are compromised, If you’ve ever noticed that one of the first things a qualified HVAC technician checks on a service call is the system airflow, now you know why.

Central heating/cooling is comprised of two separate systems that function together as a loop:

  • Supply air. This is the heated or cooled air that flows from the system air handler, through the supply ductwork, and into rooms throughout the house.
  • Return air. Air drawn into the return vents in each room—or a single central return in a central location—flows through the return ducts back to the air handler to be heated or cooled again.

Common Airflow Issues

  • Dirty filter. All circulating air in your system passes through the air filter. A clogged filter restricts proper flow. Replace the filter at least every other month.
  • Pressure imbalance. The CFM (cubic feet per minute) of conditioned air entering a room through supply vent should roughly equal the volume removed through the return. If supply volume exceeds return volume, a positive pressure condition exists. Conditioned air is forced out of the house through tiny cracks, wasting energy. If the opposite happens—the return duct removes more air volume than the supply duct delivers—negative pressure occurs. Unfiltered, unconditioned air is drawn into the house, temperature control is inconsistent and air quality is compromised.
  • Deteriorating ducts. By the time a house is 10 years old, the HVAC ductwork is typically leaking conditioned air. Usually, this heated or cooled airflow leaks into the attic, crawl space or other unconditioned areas where supply or return ducts are routed. Air loss from duct leakage is a major cause of system energy inefficiency and higher costs, inconsistent temperatures, and poor air quality.

For professional solutions to HVAC airflow issues in your home, contact Mowery Heating, Cooling and Plumbing.

Our goal is to help educate our customers in Brownsburg, Indiana and surrounding areas about energy and home comfort issues (specific to HVAC systems).