image of hvac ductwork

Through a complex system, heating and cooling the home is made possible. This system isn’t just comprised of an outdoor unit and an indoor unit. There’s also a network of vents and ducts that distribute heated or cooled air to various zones or rooms. When problems arise, people often attribute them to faulty equipment, but some issues are actually related to the ductwork instead. Spotting leaky ducts can be difficult given that these structures are typically hidden from sight. There are, however, several common signs of leaky air ducts that might clue you in.

Several Signs That You’ve Got Leaky HVAC Ducts

This article will share a few common signs of leaky HVAC ducts.

1. Increases In Your Utility Bills

homeowner shocked at expensive energy costs

A leak in your HVAC ductwork will waste the efforts that your air conditioner and furnace make. Heated and cooled air will begin seeping into unwanted areas such as the attic, rather than being distributed to rooms that are in use. It will be much more difficult to achieve and maintain the desired indoor temperature which will, in turn, cause the HVAC system to consume more energy. Although their usage doesn’t increase, homeowners will notice a significant rise in their energy bills. Ignoring this problem can be costly.

2. The Home Is Excessively Dusty

image of dust in house due to poor air quality

Leaks do more than simply move conditioned air to places where it isn’t needed and doesn’t belong. A leak will also disturb hidden accumulations of dust throughout the building and force these into open areas. If you’ve got a lot more dust in your bedrooms, living room, or other general living spaces, even if household activities haven’t changed, then a duct leak is the likely culprit. Build-ups of dust can be harmful to the health of building residents. These accumulations can lead to asthma, allergies, and many other forms of respiratory distress.

3. Uneven Temperatures Throughout The Home

feeling cold due to leaky hvac ducts

As you travel from one room to another, you may notice a considerable difference in temperatures. Conditioned air should always be evenly distributed by central air systems and thus, uneven heating and cooling is usually a sign of issues. For instance, when your air conditioner is on, if you’ve got a leaky duct, this could leave colder air near the area of the leak while leaving rooms at the other end of the home without any cooling. This is a classic sign of leaky ducts that’s pretty difficult to overlook. Those in the affected areas of the home may try adjusting the thermostat setting, but they won’t get relief until the leaks are resolved.

4. Other Decreases In Indoor Air Quality

In addition to bringing more dust into the general living environment, a duct leak can also result in the spread of toxic fumes that cause illness. Air can be pulled from the basement or outdoors. If you have chemicals stored in your basement such as paint thinners and pesticides, your loved ones will be unknowingly breathing in their fumes. Strong odors should always be investigated as this could be their cause.

5. The Need For Frequent HVAC Repairs

image of an hvac contractor repairing furnace

Older systems tend to break down more often than newer heating and cooling equipment does and thus, the need for frequent repairs should cause concern if your system is relatively new. New HVAC units should perform without problems for more than a decade if they’re well-maintained. Ductwork leaks can lead to system failure by making HVAC equipment work a lot harder than it should and by expediting normal wear. Taking care of a duct leak early-on will prevent these unnecessary system damages from occurring.

How To Locate HVAC Duct Leaks

Following, we’ll talk about a few strategies that you can use to identify the exact location of leaky ducts.

1. Search For Visible Duct Tears

Check your ducts for evidence of holes and tears. Mark problem areas with a grease pencil so that they can be easily identified by the repair technician. If a problem has been persisting for several years unnoticed, you may be surprised by just how extensive it’s become.

2. Turn Your HVAC System On High

homeowner adjusting thermostat

If you can’t seem to find the location of a ductwork leak, turn your HVAC system on high so that conditioned air is forced around the home. This will make it easier to identify obvious differences in temperatures around the damaged duct. You’re pretty much assured of finding most or all of the leaks that exist.

3. Take A Look At The Duct Joints

Duct joints in HVAC ductwork are naturally weak points. Leaks commonly develop at these intersections if they haven’t been properly sealed. Run your hand over duct joints to see if the cooled air is leaking out. This is something that you can quickly do whenever you suspect a duct leak.

4. Take Duct Tape Off

image of duct tape that was use to cover hvac ductwork leak

If your home was purchased as pre-existing construction, then you should search for duct tape. Prior homeowners may have encountered leaks in the past and then used duct tape for a quick fix. It’s important to remove this tape so that your HVAC technician can implement a more permanent solution.

5. Light A Stick Of Incense

Leaks can be made visible by lighting incense or creating any other colorful smoke. The smoke will swirl a bit differently around leaky ducts so that target areas are easy to spot. This is the ideal strategy for small-sized leaks that cannot be readily detected by hand.

6. Seal Leaky Ducts

image of hvac air ducts

After you’ve completely surveyed your ductwork, take the time to seal leaky ducts one at a time. This is something that an HVAC company should do so that the problem never recurs. Technicians use permanent sealants and they also have the ability to identify any leaks that were overlooked in your own inspection. You’ll get superior results with a thorough, professional assessment.

7. Perform A Fog Test

After sealing all the duct leaks, test your ducts by renting a fog machine. If any holes still remain, this method will help you discover them. This strategy is best performed after all large-sized leaks have been sealed as it won’t flood the basement or attic areas with smoke. Keep in mind, however, that HVAC technicians have the necessary experience and the right tools for accurately spotting duct leaks. They can also use the best repair strategies for fixing leaking HVAC ducts so that your home heating and cooling system can perform exactly as it should.


All HVAC problems and situations are unique. In some cases, some of the strategies shared here will work better than they will in others. HVAC companies know which strategies to use and when each technique will solve the problem. They’ll identify all problems until all of the ducts throughout your home have been properly sealed. You’ll have the benefit of lower energy bills, even heating and cooling throughout the building, less frequent repair issues, better indoor air quality, and longer-lasting HVAC equipment.

Get Effective Heating & Cooling Solutions By Calling Tower Energy

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Hartford County, Connecticut residents can get superior heating and cooling repairs from Tower Energy. Our staff is comprised of professionally certified HVAC technicians who are capable of performing reliable HVAC installation, repair, and replacement services. They are seasoned and knowledgeable and can do the job right. We offer a number of practical and proven solutions for improving indoor air qualities, efficiency, and home comfort.

Throughout the area, you’ll always get the most competitive prices on HVAC services from Tower Energy. You can extend the lifespan of your HVAC equipment and limit your energy bills with our top-rated maintenance services. When it’s time to have your HVAC equipment replaced, we’ll assist you in finding the right model or components for your household and your budget. Our work comes backed with a satisfaction guarantee. To schedule service, call Tower Energy. You can get an in-home estimate from us absolutely free.

Contact us now or call us at (860) 677-7347 to find out more.