Those of us in the HVAC industry are quick to encourage homeowners to change their air filters often and to use a good-quality air filter. Doing so will help preserve the life of your HVAC system and ensure that it works well and needs fewer repairs over time. A clean filter also promotes energy efficiency. However, there are occasions when filter damage can occur, so it’s wise for homeowners to know what kind of filter is best for their system.

Avoiding Filter Damage

Flimsy fiberglass filters will keep larger particles of dirt out of your system but do little to improve indoor air quality. Experts generally recommend using a filter that’s higher on the MERV (minimum efficiency reporting value) scale, which rates filters for effectiveness on a scale of 1 to 20. However, you may choose a filter rated, say, 13, and find that it slows airflow down too much and causes your system to work harder. By choosing a pleated filter that’s rated slightly lower, you can get good filtration and better IAQ but avoid filter damage to your HVAC. Thick filters also hold more dust without blocking airflow due to the pleated material and increased surface area, and they have a longer life of at least three months.

Homeowners should be wary of installing HEPA (high efficiency particulate air) filters. These are extremely dense filters and cannot be used with a typical residential HVAC system without extensive modifications to the system.

Concerns about improving IAQ should probably be addressed with the use of some kind of air-purification system, rather than by using a filter rated higher than MERV 12.

Dirty-Filter Damage

How does dirty-filter damage occur?

• By restricting the airflow in the air handler, which strains the motor, leading to possible burnout, overheating, and failure.
• By allowing ducts to get dirty faster, leading to the need for cleaning.
• By allowing coils to get dirty faster, causing the system to work harder — and perhaps freeze and burn out.

To learn more about filter damage, contact Powers Heating and Air of Peachtree City.