Duct cleaning has never been proven to actually prevent health problems, nor do studies conclusively show that particles in air ducts can enter the living space. If you or someone in your family has asthma or allergies, you may be considering cleaning your home's heating and air conditioning ducts. But even if you don't have special health problems, cleaning your ducts may appeal to you on an intuitive level. After all, if the ducts are clean, all the air coming out of the vents should also come out clean, right?Companies that clean ducts often announce health benefits or suggest that cleaning ducts will reduce energy bills by improving system efficiency.
Some ads even use phrases such as: “Studies have shown that...” but there is no data to support these claims. Even if the ducts are dirty, cleaning them probably won't provide any measurable benefit. In fact, the few independent research conducted on duct cleaning indicates that the process accumulates so much dust that it creates a greater problem than it solves. After all, it makes sense to clean the ducts intuitively, but the rest of the house is dusted off and the rest of the house is cleaned.
The truth is that the dust that settles in the ventilation system usually stays where it is and is unlikely to reach the air unless it changes. Under most circumstances, dust is inert and harmless, and removing it with cleaning equipment actually creates major problems. Little research has been done on the effects of duct cleaning. Studies conducted by the governments of the United States and Canada and health professionals who have researched duct cleaning go so far as to recommend its use, but neither do they support it as a routine measure. EPA and CMHC researchers used different methodologies.
The CMHC study used several duct cleaning services. The companies were not informed that they were part of a study and the researchers did not control the time spent or the methods used. The EPA study prescribed and controlled the methods used in a smaller number of homes. While the duct cleaning industry maintains that both studies are flawed, no other research has questioned the findings. And while the equipment and methods used by duct cleaning companies have changed since these studies were conducted, household air ducts haven't.
Changing air filters frequently is the best way to keep dust, allergens, and other particles out of the home. With a newly installed system or one in a house you just moved into, check the filter once a month to determine how quickly it gets dirty at different times of the year. Most should be replaced every two to three months. Although not always part of their basic cleaning services, many duct cleaning companies also tend to clean heating and cooling equipment (heat exchangers, cooling coils, condensate drain pans, fan motors, fan blades and fan housings). While much of the energy used to power heating and cooling equipment is wasted, that waste is due to equipment inefficiency, poor insulation, leaks around doors and windows, and unsealed ductwork.
While there are some benefits to cleaning and maintaining heating and air conditioning equipment, these benefits are relatively small and little energy waste is attributed to dirty ducts or equipment. The CMHC researchers found that when duct cleaners also cleaned the fan blades there was a small reduction of particles suspended in the air. Cleaning the fan could also slightly improve the energy efficiency of the system. The same goes for evaporator coils in your home cooling system which cause condensation and dehumidify air before it circulates around your house.
Condensed moisture can cause dust and other particles to adhere to coils and accumulate in them. In addition by cleaning collector tray (and draining nozzle) located under coils it is ensured that dirt does not accumulate and enter system as well as prevents water from accumulating in and under coils which can cause mold problems. Also consider inspecting your duct system for leaks as leaking ducts reduce efficiency and introduce air quality problems. If any member of your household has specific health problems such as allergies or asthma consult your doctor first as it is important to identify problem so doctor can suggest alternatives to cleaning ducts. Start by identifying if ducts are part of problem (they probably aren't) and if cleaning them will help (it probably isn't).
If you suspect you have mold problem either because of visible growth or because of musty smell constantly coming out of supply grilles then cleaning ducts won't do much good if it doesn't get rid of mold as mold starts with moisture problem and ducts themselves are unlikely to be cause. Most likely culprits are cooling system's evaporator coils which your heating and air conditioning contractor and most duct cleaning companies can inspect and maintain as well as leaky return ducts which can introduce moisture too. Ordering things only helps to certain extent if in first place you keep buying too much so while not necessarily bad idea truth is that it's not necessary in most cases as in fact cleaning normally dusty ducts provides no real value if done properly then can be useful in limited situations such as an air conditioning system not working properly ineffective air filters poorly installed ducts or accumulation of moisture which can cause air ducts to be contaminated.
