Ductwork serves as a conduit for air that moves through the heating and cooling system of your home. Much planning goes into duct design to ensure the space has proper temperature control, air pressure and ventilation. Sizing your ducts is part of that process. If ductwork banging is keeping you up at night, the sizing may not be quite right.
The likely cause of this noise is the expanding and contracting of metal ducts. Ideally, proper sizing and design of the network will prevent this problem. If not, the metal may flux with changes in the temperature. Since the ductwork delivers conditioned air, these changes happen often, especially in Arizona where air conditioning is vital. You may hear the noise in two stages. The first will occur while the system is running. When it turns off, the temperature of the metal goes back to normal and you will hear the noise again.
Noises that point to metal expansion:
Rattling happens when something is loose. This is true with ducts, as well. If the noise you hear is a rattle, then the cause may be a loose fitting in the system. You will hear the rattling when either the furnace or air conditioner is running.
Silencing the Noise
To fix the problem, you must find the misbehaving section of duct. When the ductwork banging begins, walk around until you locate the problem area. From there, you have several options to silence the noise. You might add insulation or attach a brace to secure a loose piece. For hard-to-reach areas, it’s best to hire a qualified professional.
Contact us at Rite-Way Ventilating Co. for ductwork service, or for any of your heating and cooling needs. We have proudly serve the Tucson area since 1959.
Our goal is to help educate our customers about energy and home comfort issues (specific to HVAC systems). For more information about ductwork and other HVAC topics, download our free Home Comfort Resource guide.