5 Tips for Reducing Heating Duct Noise

A close-up photo of the inside of a heating duct.

Heating duct noise and vibration can be an irritating addition to your home heating and air conditioning system. If you are experiencing too much noise or rattling from your heating ducts or ventilation system there are a number of things you can check and alter to ensure a more quiet performance in the future.

1. Internal and External

One of the major contributors to the noise element of a heating duct is the relationship between the internal and external components. The internal and external parts should not be linked together in such a way that they cause each other to vibrate and send sounds through the ducts. As much as heating and ventilation ducts are carriers of cold and warm air, they also carry a large amount of acoustic noise. The noise generated by the heating system will travel through the ducts and cause sounds such as vibration, howling, and possibly, in some cases, buzzing or whining. Prevent this by making sure that your internal ducts are connected in an independent way to the external system.

2. Insulation

You can also insulate your heating duct system. Most noise that travels down heating ducts is conducted from the air handler. The metal air handling box contains some components which vibrate as a result of the motor and movement. Insulating the air handler will dampen the noise generated by the internal components and send less reverberation into the duct vents. Thick insulation and padding will help to control any noises that escape externally as well. These can have an effect on nearby properties and close neighbors.

3. Acoustic Insulation

By using sound-absorbing materials, you can decrease the level of noise exuded from your heating and air conditioning vents. The materials are acoustically dead and will absorb noises coming from the system. The absorption will deaden the noises so that they decrease in intensity and lessen the further along they travel, eventually disappearing. Sound dampening insulation can be fitted along the lengths of ducts in the same way you would insulate piping, by lagging the outside.

4. Cleaning and Maintenance

Regular cleaning and maintenance will also keep your heating, ventilation, and air conditioning system operating at peak performance. By having it professionally cleaned and maintained, you will reduce the actual noise by keeping the parts in good condition and making sure that all the elements are fitted together correctly. Having gaps or loose components in your duct system will not be conducive to keeping it running smoothly or quietly.

5. The Fan

Regular cleaning of the fan is also vital to the smooth operation of your heating system, as the fan attracts dirt and dust. The output of acoustics from your fan could be the major cause of most of your noise. It should be maintained correctly and regularly and serviced when required. The fan should also be the correct size and level for your particular system. If it is under performing because it is too small to cope with the work, it should be replaced with a more appropriate size.