What is a common sign of blocked airflow in an HVAC system?

A common sign of blocked airflow in an HVAC system is uneven heating or cooling. When airflow is obstructed, it prevents the conditioned air from circulating effectively throughout a space. This blockage can lead to certain areas being inadequately heated or cooled, while others may receive an excessive or normal amount of temperature control. As a result, some rooms might feel stuffy and warm, while others might remain uncomfortably cool.

The presence of uneven temperatures directly indicates that the HVAC system is unable to distribute air uniformly due to the obstruction. This can be caused by various issues, such as dirty filters, closed or blocked vents, or issues within the ductwork that prevent air from flowing properly.

While other symptoms, like increased humidity levels or rapid cycling of the system, can also occur due to airflow issues, they are not as directly indicative of blocked airflow as the presence of uneven heating or cooling. Rapid cycling, for instance, may occur due to other factors like a malfunctioning thermostat or refrigerant issues that do not necessarily indicate airflow problems. Thus, identifying uneven heating or cooling serves as a clear and concise signal that there is a blockage impacting the HVAC system's performance.