Most said that the customers thought that if the registers were cleaned and some sort of specialized duct cleaning machine was used, the job was performed properly. But when questioned further, not one former employee could make the claim that the entire air conditioning/heating system was cleaned. Most admitted that they personally felt they had taken advantage of the customer because they knew dirt and debris remained in the system after cleaning.

The EPA and The National Air Duct Cleaners Association (NADCA) define the term "duct cleaning" or "HVAC system cleaning" as cleaning the entire system. "The entire system" is the A/C or furnace unit, main trunk lines that connect to that unit, and all branch runs from the main trunk. NADCA goes on to define the "system to be cleaned" as any internal surface which air moves across. Therefore, any company you contract with for a "duct cleaning" should be able to prove their method of cleaning complies with the EPA and NADCA guidelines.

Listed below are some other facts that were uncovered during our survey of some former employees of these companies:

• None of the companies offer a product that allows comparison to a full duct cleaning job.

• In the initial price of approximately $10 a vent, cleaning the main ductwork trunk lines is not included.

• When the system unit is included, it is left unclear as to what will be cleaned. These companies clean only portions of the system unit leaving problem areas untouched, just to be able to say it has been cleaned and increase the perceived value.

• All technicians have to "up-sell" the customer after beginning the job. These companies pay up to 40% commission on any additional work or products sold after the job begins and a large part of the technician's salary is based on these commissions.

• After extensive testing and analysis at our residential duct cleaning training center, the equipment commonly used by low price competitors has been found to be ineffective after the first 10 feet of ductwork. Anyone wishing to clean more than the first 10 feet of your ductwork must use different methods of cleaning.

• This equipment was also proven ineffective on round, flexible or metal duct greater than 12" in diameter.

• The technicians were aware that the specialized equipment they were given was not capable of cleaning square fiberglass ductwork. During our test of this equipment, ductboard fiberglass duct systems were damaged during the cleaning process, which would allow fiberglass particles to enter the living environment after the system was reenergized. Additionally, with any square or rectangular duct, a round brushing system is ineffective in the corners of the ductwork, leaving debris behind.

• After hiring several of these employees, and assessing their cleaning techniques, it was clear that they had been given little or no training on what level of cleanliness should be achieved. Many of them had never been told that the entire system should be cleaned.

• Based on this lack of training and understanding, the former employees of these companies honestly felt they were performing the work correctly and had previously never been told otherwise.

• Of the employees surveyed, only 10% had any formal training in the HVAC industry. Most responded that the customer was told to contact another company when their cooling unit or furnace failed to restart after the cleaning process. Many times this would leave the customer without air conditioning or heat for a considerable period of time.

• Four of the employees who were hired and sent for retraining quit within one month after learning the accepted standard of cleaning. During their exit survey, almost all cited that this standard was "too much work," compared to the way they were used to doing things with their previous employer.

• Special emphasis is given to the theatrics of the job and much attention is paid to things that only you, the customer, will see. Being that 90% of the heating/cooling system and ductwork is hidden from your view, the main focus is to clean only what you are aware of.

• Low-cost companies are very rarely based in the town they have the phone numbers listed for. Some are out of the county and quite a few completely reside in another state. This type of long distance operation can serve to protect a company from civil litigation by unhappy customers.

Our business is very much like a house cleaning business. Imagine what you would think if you discovered that your housecleaner was only sweeping and dusting where you could see. What if upon checking, you found that they missed the top of the refrigerator, under the beds, behind knick-knacks - everywhere you couldn't see.

What if you discovered that your $10 oil change company wasn't changing the oil filter? A job half-done may sometimes be better than none at all, but will rarely achieve the desired results.

This page is dedicated to helping educate consumers. If you're thinking about getting your ducts cleaned, read through the EPA checklist linked below. After reading it, print a copy for each contractor you'll be talking to and make sure they'll guarantee that you'll be able to check all of the Yes boxes after the job is done.