Is My HVAC System Leaking Air?

Starting your air conditioner and being met with loud hissing noises can mean a few different things. Either you have reptiles setting up shop behind your walls, or there's an air leak in your ductwork. Small holes and tears in ductwork and damaged or improper sealing of dryer vents and other system connections are among the most common causes of HVAC air leaks. In many cases, minor leaks can be easily fixed with a few strips of duct tape or a line or two of caulking.

This May Also Interest You: 4 Top Air Duct Maintenance Tips

However, if your ductwork is severely damaged or you can't find the source of the leak, you may need to call a professional HVAC technician to help get your indoor air moving in the right direction.

Can an HVAC System Leak Air?

HVAC systems most often leak air through improperly sealed furnace and air conditioner cabinets and dryer vents. Air leaks often start with damaged ductwork and gaps between connections. When an HVAC system leaks air, it can lead to a host of issues, ranging from higher-than-normal energy bills to drafty indoor air and poor indoor air quality. Plus, a home can lose between 20% and 30% of its circulating air through poorly connected ductwork and small holes that cause air leaks. When your HVAC system is leaking, it must work extra hard to maintain a comfortable air temperature in your home. In addition to hiking up your electricity bills, ductwork leakage can prevent your furnace or air conditioner from operating at maximum efficiency.

How Do You Find an Air Leak in an HVAC System?

While HVAC leaks often start in the ductwork, they can also create issues with other parts of your HVAC system. Visible dust in your home's indoor air, discolored paint around return vents, poor indoor air quality and hot or cold spots in your home can all indicate a leaky HVAC system.

You can also visually inspect your ductwork for holes, tears, cracks and loose connections. To determine if your ductwork has a loose connection, turn your HVAC system on and place your hand over the metal joints that connect two ducts together. If you feel a breeze, ductwork leakage is a likely culprit.

Smoke pencil testing is another easy way to check for air leaks within your ductwork. This convenient tool is commonly used by HVAC professionals to detect leaks, and many home improvement and hardware stores carry commercial versions. Smoke pencils work by releasing small puffs of nontoxic smoke that move in response to air drafts.

More Related Articles:

• Gimme a Tax Break: 5 Things to Know to Get the Latest HVAC Tax Credits and Rebates

• How Much Does HVAC Repair and Maintenance Cost?

• Replacing Your HVAC Filter Is a Breeze! Follow These 7 Steps ...

• Is an HVAC Tune-Up Worth the Price? (Yes, Yes It Is)

• 4 Signs You Need to Replace Your Air Handler

Where Are Most HVAC Air Leaks Located?

Damaged or improperly sealed ductwork is the most common cause of HVAC air leaks. Your ductwork may be located in your home's attic, crawlspace or garage. Leaks can also occur in improperly sealed furnace cabinets, air conditioner coil cabinets and dryer vents. If your dryer vent is leaking air, there may be holes or cracks in the vent pipe, or the seal between the vent and the outside of your home may be loose.

How Are HVAC Leaks Fixed?

Depending on the location and extent of the damage, HVAC air leaks can be fixed in a variety of ways. For example, an air leak around your dryer vent may be easy to fix in a DIY fashion by applying fire-safe silicone caulking to the problem areas. If the leaks are located in your ductwork, applying metallic tape to the leaky areas may be enough to prevent future issues. Adding insulation to your ductwork is another solution that may stop air leaks in their tracks.

If you're not comfortable with DIY repairs, contact a licensed HVAC technician for assistance. In addition to being highly trained and experienced, HVAC professionals have the right tools and equipment to safely locate the exact source of the air leak and perform the necessary repairs to get your system back on track.