Are all HVAC air filters the same? No, HVAC air filters vary in quality and size, and some have specs that others don't. Mostly we recommend purchasing the filter your HVAC manufacturer recommends pairing up with your installed equipment, though you could be tempted to try another filter type for convenience or to remove more debris from your residence. Filters have MERV ratings, which range from 1-20. MERV is an acronym for "minimum efficiency reporting value". A higher MERV rating means fewer pollutants pass through, and it captures finer particulates. This sounds like a good thing, and it can be, but a filter that eliminates finer dust and dirt will also clog up more often, and pressure on your system will go up. If your system has not been designed to operate with this kind of filter, it can actually reduce your airflow within your house, putting the hurt on your comfort and energy costs. So what should you know before you buy? Unless you live in a hospital, you probably don't need a MERV rating above 13. Fun fact, most residential units are specifically designed to work with a filter with a MERV rating below 13, and frequently you will learn that quality systems have been made to work with a MERV rating of 8 or 11. All filters with a MERV rating of five should block most of the major nuisances people care about such as pollen, pet dander, and dirt. While some filters claim to be able to catch mold spores, we recommend removing any mold from your home you find, instead of trying to hide the issue with a finer filter. Frequently the packaging indicates how often your filter ought to be replaced. There are one-month filters and there are 3-month filters. Additionally we have filters that are made flat like screen windows, and you have some that are ridged with supporting wire. In our experience, the accordian style filters fare better, and are worth the extra pennies. You could also consider washable filters, also known as reusable filters. Some homeowners like the environmentally friendly aspect of it, as they don't add to a wasteyard, and others believe it's more convenient to just pull out the filter and wash it off rather than making a run to the local hardware store for a filter of the right size. These filters are often made to endure several years and will save you cash over the long run, though they are more expensive initially. However, washable filters have to be dried out all the way before returning it back to prevent mold growth in your ductwork. In addition, most washable filters usually have a MERV rating between 1 and 4, and they lose their efficiency over time. Some washable filters have been built with new tech, such as electrostatic air filters, that are meant to effectively improve the MERV rating. Finally, filters are built with different materials. Fiberglass filters are what we see most often, and are the disposable type. Polyester and pleated filters can catch more debris, but also reduce the airflow in your residence. And there are high efficiency particulate arrestance filters, which you may know as HEPA. While you may be tempted to put in a HEPA filter, keep in mind that's like putting a MERV 16 filter in your HVAC system and it's highly unlikely that your system was built to handle that kind of resistance. Back To Frequently Asked Questions