Per ACCA Manual D, what is the friction rate range that is recommended?

The recommended friction rate range according to the ACCA Manual D is important because it directly impacts the efficiency and performance of duct systems in HVAC applications. This friction rate indicates the resistance to airflow within the ducts, affecting the system's ability to provide adequate heating or cooling.

The range of more than 0.06 and less than 0.18 is optimal as it balances airflow efficiency with minimal energy consumption. If the friction rate is too low, it may indicate oversized ducts, which can lead to inadequate airflow control and increased energy costs. Conversely, if the friction is too high, this can cause excessive noise, increased fan power requirements, and potential comfort issues due to poor air distribution.

Understanding this range helps HVAC professionals design systems that maximize performance while minimizing energy use, ensuring both comfort and operational efficiency in residential and commercial spaces.