Signs Your HVAC Air Ducts Are Leaking

image of hvac ductwork

Household heating and cooling are made possible by a complex system. It’s not just an indoor unit and an outdoor unit. There is a network of ducts and vents responsible for distributing hot or cold air to different rooms. It is common to suspect faulty equipment when issues develop but the problem may actually be coming from the ductwork. It’s hard to spot leaks across ducts since these are usually hidden away. However, there are signs of leaky air ducts that strengthen this hypothesis.

Explore Our HVAC Services Call To Schedule A Free, In-Home Consultation

Signs Your HVAC Air Ducts Are Leaking

In this article, we discuss some of the most common signs that you may have a leak in your HVAC ductwork.

1. Higher Utility Bills

image of woman looking at high heating and cooling bill

HVAC ductwork leaks waste the efforts of the furnace and air conditioner. Hot and cold air goes to unwanted areas like the attic instead of moving to the occupied rooms. The desired temperatures are harder to reach and maintain so the system consumes more energy. Homeowners will notice this with their increasing utility bills despite steady usage. Indeed, this is a costly problem to ignore.

Call Today: (856) 665-4545

2. Noticeable Dustiness In The Home

Leaks don’t just move the air where it shouldn’t be. They can also disturb beds of dust from the hidden areas of the house and push them out into the open. If you are noticing more dust in the living room and the bedrooms, even if there are no changes in household activities, then this might be the culprit. Such a build-up may be detrimental to the health of the family. It can lead to allergies, asthma, and other respiratory issues.

3. Uneven Heating And Cooling

feeling cold due leaky hvac ducts

When moving from room to room, you might observe a noticeable difference in temperatures in these areas. Central air systems should distribute conditioned air evenly so this kind of situation may indicate a problem. When using your air conditioner, for example, HVAC ductwork leaks might lead to colder air near the problematic ducts while the rooms at the far end no longer receive much cooling. This is one of the classic signs that you cannot miss. Occupants of the affected areas might try to adjust the thermostat but there won’t be much progress until the leaks are addressed.

Learn More About Our Heating & Cooling Services Call To Schedule A Free Consultation

4. Other Negative Effects On Indoor Air Quality

Aside from scattering dust to different areas of the house, the ductwork leaks may also spread toxic fumes that make people ill. Air may be pulled in from the outside or from the basement. If there are chemicals stored in there like pesticides, thinners, and the like, then the family could be breathing in their fumes without knowing it. Investigate any strong odors as this might be the cause.

5. HVAC System Requires Frequent Repairs

furnace repair service

It is not unusual for older HVAC systems to break down frequently but this would raise an eyebrow if you are dealing with a fairly new system with only a few years under its belt. Newer HVAC units should last for over a decade when properly maintained. Leaky air ducts can contribute to equipment failure by making the system work harder, inducing wear and tear. Early intervention can prevent this situation from occurring.

Call To Schedule An Appointment

Steps To Take To Locate Leaks In Your HVAC Ductwork

Below, we discuss some of the best methods to pinpoint where your leak may be occurring.

1. Find Visible Tears In the Ductwork

Inspect the ductwork to look for holes and tears. Use a grease pencil to mark the problem areas so that these can be found quickly when you are ready to have them repaired. You might be shocked to discover the extent of the problem which has been worsening over the years.

2. Turn The HVAC System On Full Blast

thermostat and comfort control

If you are having trouble locating these leaks, then turn the HVAC system on full blast to force conditioned air around the home. It will be easier to feel the obvious temperature difference around duct tears. You can be confident about finding most, if not all of them.

3. Inspect The Duct Joints

The duct joints are naturally weak points. It is common for leaks to develop around them if they were not sealed properly. Try to run your hand over these joints and feel whether there is cold air coming out of them. Do this wherever you suspect leakage.

4. Remove Duct Tape

image of duct tape that was removed from hvac ductwork

If you bought the house from a previous owner, then you might want to check for the presence of duct tape. They might have encountered leaks before and used this as a temporary solution. It’s best to get rid of this tape so that a technician can perform permanent sealing.

Explore Our HVAC Repair Services Call To Make An Appointment

5. Light Incense

You can make the leaks visible through the use of incense or any other colorful smoke. Affected areas around the duct will make the smoke swirl differently so you can spot your targets immediately. This is great for small leaks that you might not easily detect with your hands.

6. Seal The Leaks

hvac ductwork repair

Once you have completed your survey of the situation, you can begin to seal the ducts one by one. However, you should let an experienced HVAC technician handle this so that it never becomes a problem again. Technicians can apply permanent seals and may even discover additional leaks that you missed during your inspection. Their thorough assessment will lead to better results.

Call To Schedule A Free Estimate

7. Test With Fog

After sealing all the ductwork leaks, you can rent a fog machine to test the ducts. If there are any holes left, then you will discover them with this method. This works better after sealing most of the bigger holes because it will not overwhelm the attic and basement with smoke. However, once again, HVAC contractors have the necessary tools and experience to find leaks more accurately. They also know the best methods to repair leaky HVAC ductwork so that your system can perform as expected.



Every situation is different. Some of the techniques presented will work better than others in certain cases. An HVAC technician will know exactly which to use and when to use them. They will hunt down all of the problem areas until you have properly sealed ducts throughout your house. Enjoy lower energy bills, even temperatures, fewer repairs, longer system life, and higher indoor air quality.

Call McAllister Energy For Effective Heating Solutions

McAllister Energy

McAllister Energy offers superior heating and cooling services in Camden County, New Jersey. We have professionally certified technicians on staff who can provide you with excellent HVAC tune-ups, repairs, installations, and replacements. Each of our techs has the knowledge and experience to service your HVAC system correctly. We can provide you with practical solutions to improve your air quality, increase system efficiency, and enhance your comfort.

McAllister Energy guarantees the most competitive heating and cooling service costs in the area. Our maintenance services can prolong your HVAC system’s lifespan and reduce your home heating and cooling costs. If you happen to need an HVAC repair or replacement system, we can recommend the best one for your home while staying within your budget. We back all of our work with a guarantee to ensure your satisfaction. To schedule a service appointment, give McAllister Energy a call today. We offer free, in-home estimates.

Call Now: (856) 665-4545 Read Our Reviews

You can click here to contact us now or call us at (856) 665-4545 to find out more!