What does CFM measure in an HVAC system?

CFM, which stands for Cubic Feet per Minute, is a measurement that quantifies the volume of air movement within an HVAC system. It is used to assess how much air is being circulated or moved by the system within a given time frame, which is critical for ensuring adequate ventilation, heating, and cooling in a space.

In HVAC applications, understanding CFM is essential for proper system sizing, ensuring that the HVAC unit can effectively replace or condition the air in the designated area. For example, if a system has too low of a CFM rating, it may not provide sufficient airflow to maintain comfort levels in a room, leading to hot or cold spots. Conversely, excessive airflow may result in higher energy consumption without improved performance.

The other options focus on different aspects of air properties that are not directly related to CFM. While temperature measures the heat content of the air, pressure assesses how forceful the air is within the system, and resistance pertains to how much the airflow is impeded by ducts and components. None of these directly involve measuring the volume of air movement, which is why CFM specifically measures the volume of air movement in HVAC systems.