October 27th, 2018 8:51 PM by Dan Howard
Most of us have heard of “Duct Cleaning Services”. The goal of this service is to stop the spread of the dirt and debris from the ductwork into the air we breathe. By debris we include mold spores, dust mites, pollen, pet allergens. house dust, and a host of other particles. These “airborne chunks” can affect respiratory health, induce allergies and are disgusting to know that we are breathing. Cleaning ductwork is an essential part of a healthy indoor air environment that is recommended after most mold remediation jobs and for respiratory health patients.
There are many choices in the duct cleaning service industry and a wide range of price points and quality of workmanship. Most people do like to save money, but also want the job to be done correctly.
The typical cost of a quality duct cleaning job in a 3-bedroom average size home is usually in the $500 to $800 range depending upon the amount of ductwork and the way it is laid out. This is an important job that should be done correctly. A “once over and not look back” budget coupon job is not worth the money no matter how low the price.
So How is a Consumer to Know if They are Getting a Good Job?
Great question! Let’s talk about how the job should be properly preformed. My previous understanding of the process was through literature and technical videos. To get a better understanding of the process, I asked Mold Medics of Greater Pittsburgh to allow me to go on a job with them and watch the actual work being done.
The air duct registers should be removed and cleaned. The ductwork sections closest to the register is then swept out with a HEPA vacuum. There are usually large chunks of fallen dirt and debris from original construction and the regular sweeping of floors in the ductwork near registers.
It is best to vacuum out the dirt near the registers out of the ductwork rather than pushing it through the rest of the ductwork. After sweeping out the ductwork close to the registers, the openings in the registers are covered with a plastic film to create a seal. This is done to maximize the suction on the individual section of the ductwork lines as it is cleaned.
The Proper Equipment and Workmanship is Critical to Having the Duct Cleaning Job Done Right.
There should be a massive vacuum machine to suction dirt. By massive I mean about six feet tall and a couple of feet in diameter. It can set in a service truck or be wheeled into the home. Most technicians will bring the machine into the home for optimal suction. The 6” or larger suction hose is attached first to the return air system after cutting a hole in the ductwork. The is also a separate air compressor to push the dirt down the ductwork into the suction machine.
One by one, each duct has the temporary plastic cover removed from the opening where the register was removed. The surfaces of the ductwork are agitated with a spinning “whip” made of plastic ribbons mounted on a flexible pipe. That whip hose also supplies the compressed air to loosen the dirt. This compressed air is pushing the dirt down the length of the duct while the vacuum equipment is sucking in that dirt and debris from where the suction pipe is attached near the furnace.
Once all the individual ductwork runs to the rooms have been cleaned, it is time to clean the main horizontal runs. These main ducts are usually on the ceiling of the basement or along the joists of the attic depending on where the furnace is located.
Cleaning these longer horizontal runs requires cutting a one-inch round access holes every few feet. The combination whip and compressed air hose is inserted into the end of the ductwork most distant from the furnace. Each duct is cleaned, and the dirt pushed toward the furnace area section by section. The access holes in the ductwork are then filled with plastic caps once that process of pushing the dirt and debris toward the furnace is complete.
High quality suction and compressor equipment is needed to move the dirt from the ductwork to the massive collection bag in the suction machine. To the contrary, low quality equipment can loosen the debris in the ductwork and unfortunately result in increased levels of the dirt and debris in the air from the ductwork.
The cleaning ductwork process leaves us with dirt in the furnace main return air duct, plenum, furnace blower and air conditioner A-coil.
No job is done until the holes cut in ductwork are filled, the registers are back in place and the tools and equipment are out of the home.
Poor Quality Duct Cleaning Jobs are More Common than You Might Think
I often check the condition of the blower, return air and other components of the furnace during an environmental assessment. When I check these in a building where a duct cleaning job has already been completed, more that 50% of those cleaning jobs still have heavy levels of dirt and debris in these areas. Some of the A-coils have even been covered in mold growth after a “duct cleaning.” I have also removed registers and reached down the ductwork and been able to pick up pieces of dirt after a cleaning. This is disgusting for me and disheartening for the people who paid to have their ducts cleaned.