Anything less than a perfect installation job on your home air conditioning system duct could mean that you are losing output and wasting money. The most common way is through leaks in the duct work. But even with a perfectly installed system, normal use will eventually result in inefficient distribution from your forced air system. The only way to guarantee maximum efficiency of your forced air system is to ensure the integrity of your system’s duct work. The duct work in your home is extremely vulnerable to leaks. The air that escapes through those leaks translates to money wasted as homeowners lose up to 30 percent of their output to gaps in duct work, according to the United States Department of Energy.
Your forced air HVAC system is a cyclical network of trunk lines, duct fittings, supply runs, and boots which connect to each other in dozens of locations both hidden and visible. Air from the main unit is moved through a large trunk line into a series of supply runs which distribute air to each room in your home. Air is returned and vented through a similar network which reconditions the air and sends it back out again. Each spot where a trunk line attaches to a supply run, where the supply run attaches to the wall, floor, or ceiling, or at any similar fitting along the air return path is a potential location for air seepage. Depending on the size of your home, that could add up to dozens of opportunities for air to escape before ever reaching its target... you.
Signs You May Have Leaky Duct Work
There are number of things that you can look for which may signal the existence of inefficient air conditioning ducts in your home. First, you may notice higher than normal utility bills. If you can rule out other possible causes for this, like hotter than normal weather or extra lights and other electrical appliances being used in your home, a high electric bill might mean that your air conditioning is having to work harder and run longer. If it is working overtime, it is probably because up to one-third of the air it is cooling is not making it to the rooms in your home.
Maybe you have noticed that some rooms in your home are more difficult to cool or seem “stuffy” in comparison to others. This could signal a leaky duct in one specific supply run or at a connection to the wall, floor, or ceiling where the air is pumped into the room.
Perhaps some of your ducts are installed in areas which are not climate controlled such as attics, crawlspaces, or garages. When the air temperature surrounding these ducts is frequently changing, the ducts can expand and contract. Over time, this shifting and flexing can create gaps in fittings and boots.
The simplest way to identify leaks is by looking at areas you can easily reach. Sometimes you can actually see kinks or tangles in your duct work which are likely locations for cool air to escape.
Regardless of how you find these leaks or where they are located, sealing them is the best way to increase the overall efficiency of your forced air system.
Sealing Your Air Conditioning Duct Work
To prevent this needless waste of money and energy which could be occurring in your home, a licensed HVAC technician can seal the leaks in your system’s duct work leaving you cool and comfortable with more money in your pocket. The process is simple.
First, a mastic sealant is painted on at each connection point in the duct work throughout your home. Mastic is an epoxy, or glue, which dries to create a stiff and strong assembly while also remaining flexible enough to withstand the expansion and contraction which occurs with changes in air temperature.
To reinforce the sealant at a particularly vulnerable sight, regulation duct tape can be applied over the mastic once it has dried. It is important to use only regulation duct tape designed specifically for this purpose because regular duct tape is not strong enough to withstand the constant movement of the ducts. Regulation duct tape contains reinforced layers of metallic fiber which work alongside the mastic to create a tight but flexible seal.
Finally, insulation can be added around duct work which is regularly exposed to extremely hot or cold temperatures like those in attics, crawlspaces, and garages.
Specific areas on which a technician should focus may include fittings and boots. Fittings are used to maneuver the trunk line and supply runs to avoid obstacles such as pipes or beams or to simply change direction to send the air to different rooms in the home. Fittings are also used anyplace the trunk line or supply run needs to change sizes as determined by the amount of air that needs to be moved. Boots are attached where a duct meets the HVAC unit, a wall, floor, ceiling, or flue.
Make sure that you are not one of the millions of Americans who are throwing money out the window due to leaks in your HVAC system. Have your ducts sealed as soon as possible and be the coolest house on your block.