Are All Air Filters the Same? Understanding the Various Types of Air Filters

An air filter is an integral part of a heating and cooling system. It traps small particles in the air as it circulates through the system and keeps them from going back into the building. These particles may cause allergic reactions, respiratory problems, and other health issues.

The American Society of Heating, Refrigerating, and Air-Conditioning Engineers has been encouraging the adoption of air filters with a minimum MERV (minimum efficiency reporting value). MERV measures the ability of a filter to remove particles both large and small.

Different Types of Air Filters

A few types of available air filters meet necessary standards and are common in both residential and commercial systems.

Fiberglass Panel Filters

Fiberglass filters are layers of interwoven glass strands supported by a metal frame to prevent collapse. Fiberglass filters are the most common panel or square filter and are meant to be thrown away and replaced after roughly a year of use.

Polyester and Other Panel Filters

Panel filters also come in materials other than fiberglass. These air filters are more effective but more expensive and are meant to be replaced annually.

Pleated Filters

These are similar to the traditional panel filter, but the added pleats increase the filter’s energy efficiency by as much as five times. The pleats also increase filtration capabilities. Pleated filters must be replaced yearly.

Washable HVAC Filters

Washable filters are more cost effective than panel or pleated filters, because they do not need replacing, only regular cleaning. Cleaning consists of rinsing the filter off with water and letting it dry before putting it back in the system. Small HVAC systems often use washable filters, but larger systems can use them as well.

HEPA HVAC Filters

High-efficiency particulate air (HEPA) filters most often are made from fiberglass, but the fibers are arranged to be far more effective than those in a fiberglass panel filter. A HEPA filter removes 99.7% of all particles from the air passing through it. These filters are especially helpful in the homes of allergy or asthma sufferers.

Electrostatic Air Filters

Rather than counting on a fine mesh to capture airborne particulates, electrostatic filters attract and trap particles with an electrostatic charge. They have this charge naturally and do not need electricity to keep it. Electrostatic filters offer better filtration than panel filters and do not need to be replaced, only wiped clean regularly.

Green HVAC Filters

Green filters offer a more economical and environmentally friendly alternative to fiberglass panel filters. These filters typically are made from cotton, although other green materials may be used. They do need to be replaced, but on a less-frequent schedule than other panel filters, resulting in a lower overall cost. Green filters are roughly equal in filtration capabilities to fiberglass panel filters.

The multiple types of air filters for heating and cooling systems offer home and business owners options in terms of filtration capabilities, maintenance, and cost. Choosing the right filter can save money and result in better health. If you need help purchasing the best filter for your home needs, give us a call today.