Ducts are used in heating, ventilation, and air conditioning (HVAC) to deliver and remove air. The needed airflows include, for example, supply air, return air, and exhaust air. Ducts commonly also deliver ventilation air as part of the supply air. As such, air ducts are one method of ensuring acceptable indoor air quality as well as thermal comfort.
A duct system is also called ductwork. Planning (laying out), sizing, optimizing, detailing, and finding the pressure losses through a duct system is called duct design.
Duct cleaning is one of those tasks that it’s easy to forget about. Since ducts and vents are often overlooked, many homeowners might not even remember the last time they had them attended to. The fact is, however, that duct and vent cleaning may have health advantages, and might even reduce your energy bills and extend the life of your forced air system.
One thing to consider when you’re thinking about vent and duct cleaning is the fact that indoor air quality is decreasing. This is due in part to the popularity of high-efficiency windows, doors, and increased insulation that reduce the amount of air transfer between inside and outside. Though these fixtures are great when it comes to reducing energy costs and making a room more comfortable, they are often not supplemented with any additional ventilation, causing pollutants that enter the home to remain inside instead of leaking out through drafty windows and gaps.
The verdict still isn’t in on whether or not duct and vent cleaning is going to improve indoor air quality in every situation. Though there is literature out there to support either side of the debate, we do know that in certain cases, duct cleaning is likely to find and remove harmful molds, fungus, and/or microbes from an infected system. At the very least, duct and vent cleaning is not going to do your home any harm, and there is a chance that it will actually increase the quality of your indoor air.
How Duct and Vent Cleaning Works
There are two ways of duct and vent cleaning. One system is connected into the ducting to provide suction. A high-pressure air hose is passed through the ducting to remove the particles from the interior. The other system uses a large specialized vacuum attached to a hose and a brushing system that is run through the ducting. Both systems are effective when operated by properly trained personnel.
A proper cleaning should include the following: cleaning of all registers, inside the ducting, and the interior of the heating and ventilating system.
The furnace fan must be cleaned, and if you have air conditioning or a heat pump, the coils inside the system must also be thoroughly cleaned. Finally, a disinfectant can be fogged through the cleaned system to eliminate any mold, bacteria, and dust mites that might remain.
Proper cleaning of a home should take a minimum of three to five hours, depending on the size of the house. If the home has more than one heating and cooling system, or the system is located on the roof, it can take longer. Most duct cleaning companies base their price upon square footage and/or the number of registers, systems, and levels to be cleaned and charge between $90 and $125 per hour to properly clean a duct system.
If a much lower price is offered, a consumer needs to make sure that the price includes a thorough cleaning, including registers, the inside of the ductwork, and all the fans and coils. Charging extra for cleaning fans and coils is unreasonable because those steps are mandatory for having a properly cleaned system.