duct cleaning- and why we DON'T do it.
By: T. Jordan
Air Monkey A/C & Heat is primarily a residential HVAC service provider. With this being said, we will, in most instances, encounter flexible duct in the attic space of a home.
Here is some food for thought: Did you know that there aren't any manufacturers of flexible duct who recommend cleaning it?
Interesting as this fact is, it is most likely due to the fact that flexible duct is comprised of three very thin layers, as described below.
1. The outer layer of foil radiant barrier.
2. The center layer of fiberglass insulation.
3. The inner layer of thin plastic vapor barrier, that has a metal slinky type of roundless guard connected to it. (This metal slinky type of material makes it very easy to damage old brittle plastic inner liners when disturbed).
The third layer that is mentioned is the area that the air inside the home was designed to be contained in while circulating throughout the duct work.
Unfortunately for many homeowners, this inner layer of duct sustains significant damage during an ill-advised cleaning of the home's fragile, flexible duct.
Once this occurs, the rate of infiltration of attic air into the duct is inadvertantly sped up due to microscopic tears and pinholes caused during the "cleaning" process- which involves running a rigid- bristled, auger-style device through the duct work. Although the damage caused is microscopic, again, this act of "cleaning" has now begun the process of rapid deterioration of the flexible duct.
What does all of this really mean? Let's take a step further to understand the applied science of the air moving throughout the ductwork.
Do you remember that word "infiltration" that we just learned about? Good, because you need to know where it is coming from, what's floating around in it, and who is breathing it in ( HInt,hint : you ).
The infiltration mentioned above is comprised of debris. Now that the ductwork has been damaged, the air is not fully contained and a vaccuum is created as supply air rushes through the duct, carrying attic -here is that word again-infiltration into each room of your home.
This debris is particulate consisting of microdust, dirt, rodent and insect feces, insect body parts and exoskeletons, as well as but not limited to pet dander, pollen, mold and bacteria. YUCK!
Your ductwork, if existing when the home was purchased by you, contains much of the previous owner's lifestyle as well. DOUBLE YUCK! This debris is already in your ductwork when you have them "cleaned".
The invisible fog of microscpoic particulate that has just been released into the supply airflow pathway will now slowly fall down through the registers from the ductwork in your home as the systems are being used over the next couple of weeks after cleaning. This invisible fog further aggrivates allergies and can cause sicknesses as well.
It should be noted that old, expired ductwork (yes, it has a shelf life) can alse deteriorate the same way. So, essentially if you have ten year old ductwork (in most cases it's beyond the 10-15 year old recommended replacement age), and have it cleaned, it is not necessarily the duct cleaner's fault. The true problem is that homeowner's are not privy to this information.
Most of the time, a homeowner wants to clean their ductwork as a means of saving money, and stretching the useful life out of the home's components. However, most homeowner's don't think about the drastic temperature changes that occur overhead.
Let's remember that this is Texas, and Texas weather is extreme. People have the benefit of escaping the extremity of the weather, but ductwork does not. Flexible duct is constantly subjected to the extreme daily temperature fluctuations of your attic space. We don't typically think about this, because we don't typically hang out on our attics.
Attic spaces in Texas are regularly over 140 degrees in the summertime, and below 30 degrees in the wintertime! This extreme (110 Degree) fluctuation will expedite the degradation of any material, even if it's new.
When you consider the costs of spending money to damage your home's flexible duct, or saving the money to replace it upon regular intervals per manufacturer's recommendations, it becomes quite clear why here at Air Monkey A/C we will not sell this disservice to our customers.
If you want to truly have an impact on the Indoor Air Quality in your home, there are three surefire steps that must be taken.
1. Upgraded equipment (Preferably 2- Stage, or Variable Speed with longer run cycles), with properly sized and sealed ductwork that will turn over the appropriate amount of air each hour for each room.
2. High quality filtration, that will remove the microscopic particulate that are drawn into the return air stream.
3. Purification that will eliminate biological contaminants, VOC, viruses and odors. Equally important is that the purification product needs to be certified to not emit Ozone during the purification process. Ozone is not only bad for the environment, it is bad for our lungs.
What have we learned?
The only true way to clean flexible duct is to replace it. That’s the simple truth! Maybe you have heard the phrase, "If it sounds too good to be true, then it probably is". This is exactly what runs through my mind when I think about cleaning old, thin, brittle, plastic vapor barriers.
Sadly, many people are sold on this unsavory practice daily. Our phone rings multiple times a day with customers asking us to clean their flexible ducts. We tell them the truth, and in many cases lose the business that they would represent because of it. In the grand scheme of things it is only a matter of time until the majority of people learn the truth about this practice, but until then, my clear conscience and honest practice sure does give Air Monkey A/C employees a good night's sleep.