In a well-functioning HVAC (heating, ventilation, and air conditioning) system, the air ducts play a crucial role in distributing conditioned air throughout a building. However, many homeowners are unaware of the impact that duct leakage and improper filter placement can have on their HVAC system’s performance and efficiency. One common issue occurs when duct leaks go unnoticed and filters are placed at the register cover (the grille where air enters or exits the duct) rather than next to the air-handling unit. This setup leaves the system vulnerable to air infiltration, potentially leading to clogged coils and blower motors, reduced efficiency, and higher maintenance costs. Understanding these risks and knowing where to place filters is essential to keeping an HVAC system running smoothly.

1. Understanding Duct Leakage and Infiltration

Duct leaks occur when there are gaps, cracks, or poorly sealed joints in the ductwork, allowing unfiltered air from the attic, basement, or other unconditioned spaces to enter. When this happens, contaminants like dust, pollen, and other particles can be pulled directly into the duct system. If filters are installed only at the register cover, they will filter the air as it exits or enters a room, but not the air entering the ductwork. This means that any unfiltered, infiltrated air coming in through leaks has a direct path to the unit.

Over time, these contaminants can accumulate on sensitive components like the evaporator coil and blower motor. This buildup restricts airflow, leading to reduced efficiency and increased wear on the system. When the coil becomes clogged, the system must work harder to maintain the desired temperature, which can lead to overheating and potentially costly repairs.

2. Why Filter Placement Matters

When filters are placed next to the air-handling unit, they can capture contaminants before they travel through the entire system. This placement provides a barrier that prevents dirt and debris from reaching the blower motor and coil. Filters at the register cover, while still beneficial for indoor air quality, do not offer the same level of protection for the internal components of the HVAC system, as they don’t stop contaminants from entering through leaks and settling within the ductwork.

3. Effects of a Clogged Coil and Blower Motor

A clogged evaporator coil and blower motor can have a range of negative impacts:

​•​Reduced Efficiency: Dirt on the evaporator coil insulates it, preventing it from effectively absorbing heat. This makes the system run longer and use more energy to maintain indoor temperatures.

​•​Increased Wear and Tear: When the blower motor has to push air through dirty or clogged components, it faces greater resistance. This causes it to work harder and can shorten its lifespan.

​•​Poor Indoor Air Quality: If the coil and blower motor are contaminated, they may release dust and other particles back into the air, reducing indoor air quality.

4. Steps to Address Duct Leakage and Filter Placement

To maintain optimal performance and extend the life of your HVAC system, it’s essential to address both duct leakage and filter placement.

​•​Inspect and Seal Ductwork: Regularly check ducts for any signs of leakage. A professional HVAC technician can perform a more thorough inspection and apply appropriate sealing materials like mastic or metal-backed tape.

​•​Use the Right Filter and Place It Correctly: Ideally, filters should be installed near the air-handling unit, where they can protect the coil and blower motor. Use high-quality filters designed for the system’s specifications.

​•​Routine Maintenance: Regular maintenance, such as cleaning coils and replacing filters, will help prevent buildup and keep the system running smoothly.

Maintain Your Ducts With Advanced Air Duct Cleaning

Proper filter placement and regular duct maintenance are vital to maintaining the efficiency and longevity of an HVAC system. By addressing duct leaks and placing filters next to the air-handling unit, homeowners can prevent air infiltration, reduce the risk of clogged coils and blower motors, and ensure cleaner, healthier indoor air. Get started today with Advanced Air Duct Cleaning.