You’ve probably experienced the feeling of confusion when trying to select the correct home air filter for your needs. What’s the best one? Should you just get the cheapest? These are just some of the questions that make selecting home air filters so mind-boggling. Let Matz-Rightway try to help you de-mystify the air filter dilemma.
Here’s an easy way to determine how efficient your old filter is (NOTE: Spare yourself a huge mess by conducting this experiment outside or with something below the filter to help keep things clear): Set the filter horizontally, then taking standard table salt, pour the salt through the filter and see how much comes out the other side. If some or all the salt falls through the filter, then you can assume that the filter will let dust pass through as well. You really should upgrade your filter to something more efficient.
There are 3 primary considerations when choosing a household air filter; Size, Material and MERV rating.
1) Filter Size
Size is the easiest factor to ascertain. Simply look at the label of your existing filter to see the dimensions, or just measure it yourself. Typically home air filters are 1” thick, but there are a number of standard width and height dimensions, and some systems have thicker filters.
2) Material & MERV Rating
Filter efficiencies are given a number from 1-16 called the MERV rating. MERV stands for Minimum Efficiency Reporting Value. This number identifies for the user, under the least efficient conditions, how well the filter is designed to capture contaminants.
As a basic example, these are some typical MERV ratings and how they connect to efficiencies. This is only a guide, so don’t forget to read the filter manufacturers’ information when purchasing specific filters.
Rating Average Filtration Efficiency
MERV 1-4 60-80%
Fiberglass, Disposable Panel, Washable metal/synthetic, self-charging (Passive)
MERV 5-8 80-95%
Pleated, Media panel, Cube
MERV 9-12 >95%
MERV 13-16 >98%
Be Careful About High MERV Ratings
While a higher MERV number may offer better filtration efficiency, it is very important to understand that too high a MERV filter may also require more to operate your HVAC system. The higher the MERV, the more difficult the air may flow through the system, and the harder the system may need to work. Your goal is to get the right balance between air flow, air filtration level and energy efficiency.
Consider it this way, the most efficient ‘filter’ would equivalent to a piece of plywood that would just trap ALL contaminants and all the air from coming inside your Long Island home. That's all-out air filtration, but would also be like living in a box.
A safe bet for most systems would be a MERV 6-8. A higher MERV filter should be used based upon the advice of your Matz-Rightway technician to confirm your system has the capability of moving the proper amount of air through higher efficiency filters. You generally do not want to sacrifice energy-efficiency for filter efficiency; you want a balance of the two. However, if your family deals with allergies or respiratory problems and a high MERV rated filter is required, consider a whole-home air filtration solution that will satisfy your energy and filter efficiency needs.
Filtration has changed considerably over the past ten years. In the beginning, home air filters were used in the furnace or air handler only to safeguard the comfort equipment itself. But (in the words of Bob Dylan) the times they are a changing. Long Island area homeowners expect their air filter to save kids from a wide variety of harmful pollutants, dust mites, and even prevent the need for dusting. Dare to dream!