Why Your Ducts Are Making a Popping Noise

Unexplained noises from your home’s HVAC equipment can cause concern, especially if you’ve never heard any before. You might wonder if it’s an animal or something serious with your HVAC system.

To eliminate undue stress, in this blog, we’ll review:

With helpful background info on why air ducts make popping noises, you’ll know if something is a normal occurrence or if you need service from a trained HVAC technician.

An important part of HVAC design and troubleshooting is understanding how static and dynamic pressure affects your ductwork. Heating and AC equipment operates in a specific pressure range within air ducts. Ductwork responds to pressure changes at times by making popping noises. This is normal, so you shouldn’t be alarmed if you hear it at times.

That said, when air duct leakage lowers the pressure or a blocked vent raises the pressure, you may end up with more serious problems that need addressing urgently. Issues with airflow and air pressure can lead to serious damage down the road, and you don’t want to risk a full system breakdown and replacement!

Ductwork materials vary from sheet metal to soft materials that a technician can gently bend for easier installation.

Sheet metal ducts tend to be square or rectangular. Metal flexing and relaxing can cause popping noises in air ducts. When these materials vibrate, they produce booming noises. If there are pressure changes in the ducts, these ducts may shift and reshape some, popping into shape once again when they rest. Round ductwork is more expensive but doesn't have the problem of flexing metal sheets, so it can be less noisy.

At George Brazil, we have ductwork specialists who can inspect, clean, and seal your ducts to improve airflow and reduce popping noises.

The gauge rating of your ductwork’s metal affects the tendency to flex and make popping noises due to pressure changes. Gauges represent the thickness of the metal; the lower the number, the thicker the metal. Most homes use 24 to 26-gauge metal, which tends to flex and pop.

If the sound issues are due to the gauge of metal in your ductwork, you may benefit from thicker ducts to reduce sounds in areas where it’s distracting. This is expensive, though, so the advice of our professionals is a valuable alternative. Contact us to speak with a professional today. We’ve been in business since 1955 and have learned a thing or two about ductwork sound issues!

Your ductwork may be too small. Ductwork design is a complex process that must consider airflow, internal static and dynamic pressures, and other factors. If your ductwork is too small, it may be sensitive to pressure changes so much that you can see it expand and contract as the heat turns on and off. That will certainly produce the popping sound you're hearing!

Incorrectly sized ductwork can have a detrimental effect on your heating and AC equipment since the equipment can withstand a specific range of pressure within the system. By checking your ductwork system's pressure and air balancing, you’ll ensure that you get the best heating and cooling distribution in your home and a longer life for your HVAC equipment.

If you have a new furnace system, you could be hearing new sounds from delayed ignition, fan and blower rattles, or other natural noises. A new furnace system or an incorrectly sized furnace can also change your ductwork's heat level or pressure requirements. If unusual sounds persist, we recommend scheduling an HVAC tune-up.

Although it may be tempting to let noises linger, calling a professional to inspect your ducts is worth the effort. They might discover that your ductwork isn’t producing the right pressure levels to minimize wear on your heating and cooling equipment, which can save you on repairs. Odd noises from your ductwork, odors, and uneven heating are reasons to investigate further.

Additionally, replacing lightweight material with more sturdy components can add durability to your HVAC system and reduce popping noises. You’ll also enjoy improved efficiency and comfort, saving you on energy bills.