Air duct cleaning takes between an hour and a full day (or longer, when cleaning commercial HVAC systems). A standard air duct cleaning would last two to three hours and would cover the HVAC unit, main return, room vents and the air ducts themselves. HVAC cleaning for a small or medium residential home can take 3-5 hours. This increase is based on the size of the ventilation system, environmental factors, commercial or industrial environments, and the age of the unit.
The time it takes to clean the air ducts will vary depending on the size of your home, the type of ventilation system you have, and the dirt in the ducts. However, on average, it usually takes two to four hours to clean all the air ducts in a typical home. The average duct system needs to be cleaned every two to five years. If your system is properly maintained and filters are changed twice a year, you can increase the time between professional cleanings.
If your system has never been cleaned and has been active on your property for more than three years, it will likely need to be cleaned. Even a single season can accumulate enough dust and debris in your system to make it less efficient than it was when it was first installed. You can easily identify if you have a clogged duct because the air flow to the room with a clogged duct will be drowned. Cleaning the ducts is not only important to increase the service life of the heating and cooling system, it is also important to improve the overall quality of system performance.
Depending on the amount of dirt, dust, and debris in your home, you may want to have your ducts cleaned every three years. When service providers arrive at your home, ask them to show you the contamination that would justify cleaning the ducts. The CMHC researchers found that when duct cleaners also cleaned the fan blades, there was a small reduction in airborne particles. Start by identifying if your ducts are part of the problem (they probably aren't) and if cleaning them will help (probably isn't).
While many of these products can legally be used inside unlined ducts if all directions on the label are followed, some of the instructions on the label may be inappropriate for use in ducts. Homeowners with children, pets, respiratory problems, or a compromised immune system may want to have their HVAC duct system cleaned more often. As long as cleaning is done correctly, there is no evidence to suggest that such cleaning is harmful. When building a new house, cleaning the air ducts works to remove drywall dust and other construction debris that accumulates in the process.
Whether or not you decide to clean the air ducts in your home, preventing water and dirt from entering the system is the most effective way to prevent contamination (see How to Avoid Duct Contamination). Researchers at the Environmental Protection Agency measured dust levels and efficiency of the HVAC system in test homes over a one-week period during the cooling season and found that cleaning the ducts did not significantly improve dust levels or performance. maintenance of HVAC equipment have some benefits, that benefit is relatively small and the little energy waste can be attributed to dirty ducts or equipment. Cleaning should be done when moving to a new house, especially if the previous owner was a smoker, pet owner, or if he did not repair the ducts in the past three years.