Air Filter Efficiency: How To Select A Top-Performing Device

The type of air filter used in your central cooling and heating equipment can make or break your indoor air quality. Many homeowners are aware of the MERV scale, which helps rate air filter efficiency in terms of the size of particles one will remove from the air. Even though this scale is important, it’s not the only factor you should consider when considering air filter efficiency.

Pressure dropair filter efficiency cleveland ohio

Also known as filter resistance, this rates what effect the filter will have on airflow in your system. High pressure drops decrease the efficiency of your HVAC unit while low pressure drops allow the heating and cooling equipment to run at maximum efficiency. The pressure drop will increase as the filter becomes clogged with debris.


The air filter efficiency rating called arrestance tests the air filter’s capability to trap dust particles. However, do not select your air filter based on this rating since it’s measured under test conditions, which tend to use larger dust particles to increase the air filter efficiency rating.

Dust spot efficiency and dust holding capacity

Dust is a common enemy in homes and can greatly affect the performance of your cooling and heating system. So it should come as no surprise that air filter efficiency is rated on how well it can remove the dust from the air and hold onto those dust particles when the pressure drops.


This rating refers to the filter’s ability to remove contaminants – mold spores, dust, bacteria, pollen and gases – from the air. When choosing an air filter based on this rating, remember the higher the efficiency, the smaller dust particle it can trap.

Initial and sustained efficiency

Several different ratings that gauge efficiency over various periods of the air filter’s life. For example, the initial efficiency rates the filter’s ability while it’s new, which does not always reflect the long-term efficiency of the filter. The sustained efficiency indicates the efficiency of the filter over its lifetime.

For more information about air filter efficiency, contact our experts at Geisel Heating, Air Conditioning & Plumping. For more than 77 years, we have provided reliable HVAC services to the Greater Cleveland area.

Our goal is to help educate our customers in Western Cleveland, Ohio about energy and home comfort issues (specific to HVAC systems).  For more information about air filter efficiency and other HVAC topics, download our free Home Comfort Resource guide.

For those Do it Yourselfers who would rather take control of your own indoor comfort, you can shop our online store for replacement parts, products and accessories!   

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