Are All HVAC Filters the Same?
Many HVAC systems you see come with an air filter system. The point of this system is to trap any unwanted contaminants, such as dust and dirt, so the air is safe to breathe in. One question that many HVAC professionals are asked is “Are all air filters the same?” No, air filters may share the same purpose, however, they are not the same.
The Types of Air Filters
There are a few types of air filters that are classified in two ways; by type and MERV rating. MERV is short for “minimum efficiency reporting value” and reflects on an air filter’s ability to trap pollutants. The rating can range from one to 20. A high rating signifies greater performance.
Here is a list of the most common air filters and their purposes:
Disposable Air Filters
Disposable filters are the least expensive type of filter. They are made of flat fiberglass or a polyester mesh that are designed to extract particles from the air. Most HVAC professionals give disposable air filters generally have a rating ranging between one to four and are mainly used to protect the HVAC unit.
Similar to disposable air filters, reusable HVAC filters are comprised of either polyester mesh or fiberglass. They are also typically given a rating of one to four and are geared toward protecting the unit. However, what sets them apart from disposable filters is that you can wash and reuse them.
Electrostatic Air Filters
Electrostatic air filters are vastly different than the two listed above. To start, they use an electric charge to trap particles as they try to go through the filtering medium. As a result, electrostatic air filters perform much better than reusable and disposable ones. These specialized air filters have an average MERV rating of 15, however, they aren’t compatible with all HVAC units.
HEPA Air Filters
HEPA air filters are the most efficient and well-known air filters to date. Many HVAC professionals give these filters an average MERV rating of 17 to a full 20. These filters are able to capture up 99.7 percent of pollutants. However, there’s a slight drawback. In order for HEPA air filters to be used to their full potential, your unit needs to exert a large amount of pressure. This makes them highly restrictive for most heaters and air conditioners. Furthermore, they are also more expensive than other types.
As you can see, air filters may share the same goal, but how they accomplish differs on what type it is. Are you in need of an air filter? Say no more! Contact Harwich Port Heating and Cooling at (508) 593-9436 and we’ll make sure you’ll be able to enjoy the fresh air!