3 Ways Your Duct System Can Contribute To Poor Air Quality

Posted on: 9 May 2017

With summer right around the corner, it's almost time for air conditioning season to begin. While the relief that an AC brings is an undeniably great thing, problems with your duct system can also lead to indoor air whose quality is far short of acceptable. If you would like to learn more about what factors contribute to poor air quality, read on. This article will discuss three problems to be aware of.


As you likely know, a residential duct system consists of dozens upon dozens of feet of ducts. This system relies on many different sections that are mechanically joined together. Unfortunately, the places where these sections meet are often subject to develop leaks. This may be the result of corrosion, physical damage, or duct tape that has worked loose with time.

Unfortunately, any such leaks will compromise your indoor air quality, since they will allow your system to pull in air from outside the duct. Those ducts often pass through dirty and dusty parts of the home—think attics and crawlspaces—whose air is anything but clean. Contaminants also often penetrate a duct system through leaky air handler cabinets and panned joist returns

Appliance Backdrafting

Gas-powered appliances such as water heaters tend to generate a lot of noxious exhaust gases as a byproduct of combustion. In a perfect world, these gases will pass harmlessly up out of your home through the flue. Problems tend to ensue, however, when duct leaks lead to changes in the air pressure of your home.

Leaks on the return side of your system—that is, the part of the system responsible for drawing air back into the air conditioner—will create a negative pressure differential inside your home. This negative pressure will affect the ability of your combustion appliances to vent properly. Basically what happens is that, instead of being drawn safely up the flue, those exhaust gases will get sucked out into the air of your home—and ultimately into the duct system through the return leaks. This is known as backdrafting.  


Duct leaks also contribute to poor air quality in yet another way: through the moisture-related growth of mold and other fungal contaminants. The problem here is that, should your system be drawing in air from damp areas such as crawlspaces, it will greatly increase the potential breeding grounds for mold, which in turn can create all sorts of health-related problems when it becomes airborne.

For additional information, contact an air conditioning repair service like CNR Air Conditioning Inc.


Summer is Upon Us – Is Your AC Working?

Hi. My name is Laurie Waters. The HVAC contractor was just out at our house last week and did I ever get a lesson from him. You see, we had a warm spell hit and I went to turn our air conditioning on for the first time since last summer. Much to my dismay, it wasn’t working. All I got was a blast of warm air. The fan was bringing the outdoor heat inside. Thank goodness it wasn’t anything major. My unit needed Freon. While he was here, the contractor taught me how to do some routine maintenance around my unit, vents, and filters. I’m going to share this information with you. I hope you find it to be useful.

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