True or False: An unbalanced duct can cause noise and vibration.

True or False: An unbalanced duct can cause noise and vibration.

• A. False
• B. Sometimes
• C. True
• D. Not sure

Answer: (C)

Airflow balance in ductwork affects both comfort and noise. When a duct system is unbalanced, some runs carry more air than others, creating velocity changes and pressure differences as the air meets turns, branches, and diffusers. This turbulence produces audible noise such as whine, hiss, or rumble. The extra flow and pressure fluctuations also put the blower and duct connections under uneven load, which can translate into vibration that travels through the ductwork and building structure. Proper balancing with dampers, ensuring correctly sized ducts, sealing leaks, and securing hangers reduces turbulence and stabilizes pressure, which tends to quiet the system. Therefore, an unbalanced duct can cause noise and vibration.

Airflow balance in ductwork affects both comfort and noise. When a duct system is unbalanced, some runs carry more air than others, creating velocity changes and pressure differences as the air meets turns, branches, and diffusers. This turbulence produces audible noise such as whine, hiss, or rumble. The extra flow and pressure fluctuations also put the blower and duct connections under uneven load, which can translate into vibration that travels through the ductwork and building structure. Proper balancing with dampers, ensuring correctly sized ducts, sealing leaks, and securing hangers reduces turbulence and stabilizes pressure, which tends to quiet the system. Therefore, an unbalanced duct can cause noise and vibration.