Have you noticed little wisps of dust puffing out from an air duct every time you turn on your home's heating, ventilation and air conditioning HVAC system? Have you seen dust or pet hair trapped in a vent? Is there dust coating the grill on the return air registers? These might be indications that your home's ductwork might be due for a thorough cleaning.

Top 5 dirty air duct indicators

Any of these indicators show that your HVAC system and ductwork are being adversely affected by too much dust and dirt:

1. Open one of your vent covers and look inside. See if it contains any dirt, debris or matted dust.
2. Examine the return air registers for dust buildup, particularly if there are thick, fuzzy coatings of dust.
3. Pull out the air filter. If the air filter is clogged with dust, then airflow is being choked off. This lets more dust settle and build up in the return ductwork.
4. Open the furnace compartment. Examine the blower fan and motor for signs of dust as well as the furnace controls. The more dust you see, the bigger the problem you have.
5. Look at the air conditioning coil. (You may need to remove a panel.) If the coil is dusty or has dust clinging to the housing walls, then the air filter hasn't been working properly.

Top 5 dirty consequences

So, what trouble is a little dirt and dust? Plenty. There are several problems caused by dirty ducts, ranging from increased energy costs to health problems:

1. Dirt and dust restrict your HVAC system's heating and cooling. In the winter, dirt-clogged heat exchangers cannot warm the air as efficiently. In the summer, dirt-clogged condensing coils are unable to cool the air as well. These both increase the HVAC systems' run time, requiring it to use more fuel and energy to heat and cool your home.
2. Dirt and dust restrict airflow. Let's say your system is doing a fine job of heating and cooling the air. But if the blower fan or motor can't turn because of dirt or the air filter is clogged with dust, then the system can't effectively circulate that properly warmed or cooled air throughout your home. It's still going to run longer and use more energy.
3. The longer your HVAC system operates, the more wear and tear it undergoes. Long run times can shorten the overall lifetime of HVAC systems, from AC compressors to hydro pumps, burners, and motor bearings. You'll wear out your home's HVAC system sooner.
4. Dust contains not only fine dirt, but also dead skin, pet dander, microorganisms from cat litter (toxoplasmosis), and other particulates such as pollen, mold spores, fungi and even rodent feces. Left to contaminate your HVAC system, it can become a breeding ground for bacteria, mites and other pests.
5. Dirt and dust spread quickly in a home with dirty ducts. No matter how diligent you may dust and clean your house, fine particulate contaminates, including dangerous allergens, quickly flow from room to room to cover tables, smartphones and children's toys.

Top 5 benefits of air duct cleaning

A visit from a professional air duct cleaning service every 3 to 5 years can prevent many maintenance and health problems before they start. Plus, you'll start saving money on heating and cooling:

1. Better and reliable overall performance from your HVAC system.
2. Fewer expensive repairs from wear and tear and longer HVAC system life.
3. More energy efficiency, reducing your energy bills.
4. Lower likelihood of respiratory and allergy problems.
5. Less dust makes it easier to clean and maintain your home's living space.

Properly cleaning your HVAC ducts is not a do-it-yourself project, nor a job for a cheap guy with an air compressor in a minivan. Thorough air duct cleaning can only be performed using industry-standard equipment designed to handle the size and volume of all kinds of homes.

While portable cleaning systems cost less and are convenient, they lack the suction power to clean out dust and debris trapped in residential ductwork. On average, a portable system uses a small compressor to move 250 cubic feet of air per minute (CFM).

Larger air duct cleaning systems mounted in trailers or vans usually rely on low horsepower engine compressors and generate more suction, usually 400 - 1,000 CFM. While that's an improvement over a portable system and might perform adequately for smaller homes, they need to be more underpowered for the average residential system.

Truck-mounted systems are best suited for most residential as well as commercial air duct cleaning. The truck's engine powers these systems and develops up to 16,000 CFM.  That kind of airflow provides A LOT of suction. You remove dust, dirt and debris from the toughest residential duct systems. Truck mounted systems are also equipped with larger vacuum bags to capture all that dust. The bags fill the back of the truck. On some powerful units, the ceiling is retracted to allow the vacuum bags to expand above the roof. Truck-mounted cleaning systems are clearly superior to the other two options. The sheer power produces greater cleaning pressures that work consistently throughout the cleaning process.

The result is an improved and more thorough cleaning that reduces harmful airborne contaminants and increases ventilation efficiency.