Submitted by Brett Lemos, owner of Airfresh Duct Cleaning

How often should I get my HVAC system cleaned?
There’s no straight answer to this question, as it depends on a number of factors, which include:

• The geographic location of your home. Are you near a freeway, forest, in the desert or on the coast?
• Weather conditions for your area.
• How old your system is.
• How often you change the filters.

Does it make a mess?
Many professionals use a negative air industrial vacuum unit with HEPA filters to capture dirt from the system while cleaning. When professionals set up to clean your system, they should protect furnishings, floors and other surfaces and carefully clean up afterward.

How do I know the ducts are dirty?
Most systems have never been cleaned before and can benefit from it. One way is to find out from the A/Company that regularly maintains your furnace.

If you don't have one, then another method you can do is open a vent from any room in the house and shine a flashlight in it. If you see a thick film of dust and debris, then it’s time to clean the system. If you see debris on the vents or notice that it comes out of vents when you turn your system on, that would also be an indication to get the system cleaned.

Lemos is the owner of Airfresh Duct Cleaning, located in Panorama City, Calif. The company has been doing business in Los Angeles for 15 years.

As of July 28, 2011, this service provider was highly rated on Angie’s List. Ratings are subject to change based on consumer feedback, so check AngiesList.com for the most up-to-date reviews. The views expressed by this author do not necessarily reflect those of Angie’s List.