Air Duct Cleaning; Is It Necessary?
(contributed by John Rogers; email: jrogers@email.unc.edu)
The impact of having your air ducts cleaned may only mean that your HVAC systems overall performance may improve.
There are numerous companies that advertise "air duct cleaning" so you may find just as many different processes. Generally, mechanical cleaning with varying sizes and types of brushes that are rotated through the duct work accomplishes the best effect. Having your heating, ventilation and air conditioning (HVAC) system cleaned professionally may take a little research on the consumers part. You will want to ask questions about how the work is to be done, what will be the process, how long to finish the job and what will the cost be at completion.
Other ideas would be to ask if they disassemble and clean the fan/blower motor assembly; not cleaning this may mean no improvement on your system's overall performance even though the ducts have been cleaned. Does their work entail a fairly large vacuuming system that connects to your duct work or do they use household or workshop type vacuums? How long will it take to do the job? A thorough cleaning may take 4, 6 or maybe 8 hours depending on the size of your house, the duct work involved and the process used to do the cleaning. Cost will vary from one company to another, just be wary of their being too detailed and too cheap. Also check on any certifications as a duct cleaner(s).
There are also many ideas about what type of filter(s) to use with your HVAC system. Most consumers are now encouraged to use some type of electrostatic filter; these vary in price and efficiency.
The idea of cleaning your HVAC system is something that may ease your "sense of wellbeing" but may not necessarily be a cure for what ails you. The field tests conducted show that the constant influx of outdoor particles, pets, occupant traffic, cooking, cleaning devices, aerosols and other cleaners used, all play a part in indoor air quality.
An EPA Report, EPA-600/R-97-137, December 1997 is available and will give more detail, ideas and other meaningful data.