Since the air ducts are the pathways by which heat and cool air reach the building, it is important to be sure they are installed efficiently and properly in order to ensure proper air flow. When an air duct is not receiving the proper airflow, it is generally due to one of several problems. This short guide will help you accurately pinpoint and diagnose airflow problems to your property.
What Are the Most Common HVAC Duct Issues?
There are various issues that can restrict proper air flow to the ducts including an improperly installed system; however, the most common issues include:
According to reports, on average, the typical building loses approximately 20-40% of air flow via its ducts, which causes the cooling and heating system to run inefficiently. Furthermore, a leaking duct can permit outside pollutants to enter the building through the ducts, which can have a negative effect on indoor air quality.
Loose or poorly sealed grills and registers prevent a secure duct connection, which enables air to escape prior to ever heating or cooling the building. When this occurs, it not only increases the building’s heating and cooling bills, but it also causes the HVAC unit to work harder, which can wear on the system and decrease its lifespan.
Uninsulated or Not Fully Insulated Ducts
In addition to leaky ducts, uninsulated or not fully insulated ducts allows cooled air to escape in the summer and heated air to escape during the cooler months.
Air ducts that have not been cleaned in a while can become dirty or clogged over time, which can affect air flow in the building as well as its indoor air quality. Once dust, germs, and pollutants build up in the air ducts, it can circulate continuously into the building once the HVAC system is in operation. In fact, it is estimated by the EPA that dirty air ducts can cause the indoor air quality of a building to be as much as one hundred times worse than it is outside.
Damaged Insulated Flexible Plastic Air Ducts
It has become a common procedure to install flexible plastic air ducts in many buildings because it is economical, easy to install, and adaptable enough to fit just about any design. However, because of its flexible material, and if it is improperly installed, it can become crushed, kinked, or torn, which results in a restriction of airflow to the building.
Improperly Designed Duct Work
An improperly designed duct system is the #1 problem with a dysfunctional HVAC system. An improperly installed or designed air duct system, even if it is the proper size and working properly, can not return the necessary airflow needed to cool or heat a building effectively.
How Duct Maintenance Can Help
If you detect an air duct issue with your building, the good news is that many issues can be easily addressed yourself, depending on the size of the building, at a fraction of the cost, except in the event you require a new system.
Addressing Leaky Ducts
To ensure proper air flow to the home and increase HVAC efficiency, it is important to seal the ducts. Sealing the ducts causes less air to escape, which enables each area of the building to enjoy comfortable temperatures without causing the HVAC system to overwork.
To address a leaking system, experts suggest sealing off all supply and return registers, then attach a dust blaster fan to an area of the flex duct with the other end attached to the existing heating duct. Determine air pressure using a pressure-and-flow gauge.
Perform the smoke test to determine if air is leaking out, then wearing protective gloves, insert duct sealant into leaky spaces. Lastly, replace all utility tape with foil-faced tape.
Addressing Uninsulated Ducts
Insulating the ducts allows temperature controlled heating and cooling to remain in the building and increases the efficiency of the system.
To use perform duct insulation, experts suggest simply removing the elbow to view the duct end. Place a plastic cap on the end of the duct, then slide the perform insulation over the duct. Carefully stretch the insulation the full length of the duct. Repeat the process on the remaining ducts.
Addressing Clogged Ducts
Getting the air ducts cleaned can greatly improve the indoor air quality of a building, not to mention cause the HVAC unit to run more efficiently.
The most efficient way to address clogged ducts is to hire an HVAC duct cleaning service. An air duct cleaning service has the proper equipment and skill to clear clogged ducts quickly and safely for improved air circulation.
Addressing Damaged Insulated Flexible Plastic Air Ducts
When installed properly, flex ducts provide a quality product with many applications, including main risers, E-boxes, lobbies, and medium pressure loop flooring. In addition, they can help reduce the level of noise. However, be prepared to pay the cost for premium grade flexible air ducts.
To repair flex ducts experts suggest using duct tape topped with duct mesh and duct mastic to seal holes and replacing crushed ducts with new ones.
Addressing an Improperly Designed Duct System
An improperly designed duct system can be addressed simply by contacting a professional HVAC service to properly reroute your system.
How Much Duct Maintenance Cost
Fortunately, most duct repairs can be done yourself, depending on the size of your project, which can help save time and money on maintenance costs. However, because of strict codes and regulations, and to avoid an improperly installed system, when installing a new airflow system, it is best to employ the services of a professional HVAC company.
They can also offer guidance in the event you choose to purchase the materials on your own. In addition, some ductwork requires a duct bank, which requires the skills of a qualified electrician, who is also knowledgeable in codes and regulations.
To determine the proper duct sizing for your building, simply use a duct sizing chart. You will need to know the square footage of each area as well as the total cubic feet per minute, and be sure your calculations are as precise as possible. If need be, use a duct size calculator.
The average cost of a new airflow system typically ranges anywhere from $35 to $55 per linear square foot, depending on the size of the building, temperature zones, number of vents, and accessibility, while professional duct cleaning typically ranges anywhere from $242 to $343.
In the end, ensuring your system is properly installed and well maintained, will help save on duct repairs and costs.