Trying to select the right air filter for your Gaithersburg home can be a daunting experience. Which brand is best? Should you just get the cheapest? These are just some of the questions that make the selection mind-boggling. Let Parker Pearce Service Experts Heating & Air Conditioning try to help you de-mystify the air filter dilemma.
Here’s a simple way to figure out how efficient your current filter is (NOTE: To avoid a big mess, we highly recommend conducting this test outside or over a protected surface): Set the filter horizontally, then with standard table salt, begin to pour the salt through the filter then see the quantity that comes out the other side. If some or all the salt falls through the filter, then you know that the filter will let dust pass through as well. You might want to upgrade your filter to higher quality filter that is 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 height by width and thickness, or just measure it yourself. Most home air filters are 1” thick, but there are a variety of standard width and height dimensions, and some systems have thicker filters.
2) Material & MERV Rating
The efficiencies of filters are rated on a scale of 16, known as MERV ratings. 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 hold contaminants.
To help explain the scale of this system, these are some typical MERV ratings and how they relate 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 provide better filtration efficiency, it is extremely important to understand that too high a MERV filter may also take more to operate your furnace and AC system. The higher the MERV, the more restricted the air may flow through the system, and the harder the system may need to work. Your objective should be to get the right balance between air flow, air filtration level and energy efficiency.
Look at it this way, the most efficient ‘filter’ would actually be a piece of plywood that prevents ALL contaminants and all the air from entering your Gaithersburg home. That's all-out air filtration, but would also be the least comfortable way to go.
A safe bet for most systems would be a MERV 6-8. A higher MERV filter should be used on the advice of your Parker Pearce Service Experts Heating & Air Conditioning technician to verify your system has the capability of moving the proper amount of air through higher efficiency filters. You probably do not want to give up energy-efficiency for filter efficiency; you want a balance of the two. However, if your family deals with allergies or respiratory problems and the situation necessitates a high MERV rated air filter, consider a whole-home air filtration solution that will achieve your energy and filter efficiency needs.
Filtration has changed considerably over the past few years. Originally, home air filters were used in the furnace or air handler only to safeguard the comfort equipment itself. The story is different today. Gaithersburg area homeowners expect their air filter to save kids from a whole host of harmful pollutants, dust mites, and even prevent the need for dusting. Dare to dream!