Heating, ventilation, and air conditioning (HVAC) systems have been shown to collect a variety of contaminants such as mold, fungi, bacteria and very small particles of dust that have the potential to affect overall health, The removal of such contaminants from the HVAC system and home should be considered one component in an overall plan to improve indoor air quality.

Frequency of cleaning depends on several factors, not the least of which is the preference of the homeowner. Some of the things that may lead a homeowner to consider more frequent cleaning include:

* smokers in the household

* pets that shed high amounts of hair and dander

* water contamination or damage to the home or HVAC system

* residents with allergies or asthma who might benefit from a reduction in the amount of indoor air pollutants in the home’s HVAC system

* after home renovations or remodeling

* prior to occupancy of a new home.

The U.S. Environmental Protection Agency says that “duct cleaning services typically – but not always – range in cost from $450 to $1,000 per heating and cooling system, depending on the services offered, the size of the system to be cleaned, system accessibility, climactic region and level of contamination” and type of duct material. 

Consumers should also beware of “blow-and-go” air duct cleaning companies. These companies often charge a nominal fee and do a poor job of cleaning the heating and cooling system.