Do Pleated Filters Reduce Airflow?

Pleated air filters are a common and recommended choice for HVAC systems, but there is still a misconception that they can damage the unit due to their ability to restrict air flow. It is true that pleated filters can reduce air flow, but this is only when the filter is too tight or has a high MERV rating. The Minimum Efficiency Report Value (MERV) rating determines the tightness of the mesh fabric of an air filter, with higher values meaning more restricted air flow. When clean air flow can pass through a pleated filter, the result is fresher, cleaner indoor air quality.

Non-pleated filters are made of fiberglass or some other electrostatic material, which is randomly woven to create a barrier through which air passes. Perfectly pleated air filters have a mesh fabric that traps and absorbs particles that pass through without restricting air flow. The disadvantage of using a pleated air filter for long periods of time is that your HVAC system will suffer from reduced air flow. As a result, the fan has to work harder to heat and cool your home, reducing efficiency.

These filters can also cause liquid to re-enter the compressor, leading to premature equipment failure. You can check the effectiveness of your pleated air filters through their MERV rating. Pleated filter widths range from 1 to 6 inches to restrict small and large particles in the air. Low MERV filters (think MERV 1) filter relatively few particles compared to high MERV filters (think 11-1).

The oven filter is a protective layer in the furnace air system, but it will eventually need to be replaced. The reduction in lifespan that results from this is avoided by changing the filter in time, not by using a cheaper filter. Air filters are especially important for homes in areas with high levels of allergens, pollutants and odors. However, while the cheapest fiberglass air filter may seem like a good idea for your budget, it may not always be the best choice for your home, your air conditioning system, or your family's health. To help you keep things clean during maintenance, pleated air filters are ideal for trapping dust and particles. When properly installed, high-efficiency filters prevent air leakage that passes through the system.

See What happens if my return air filter is improperly installed for more information and to determine if the air filter is installed correctly.