Trying to select the right air filter for your Charlotte home can be a daunting experience. What’s the best one? Does the price reflect the quality? These are just a couple of the questions that make the selection mind-boggling. Let Komfort Air try to help you de-mystify the air filter dilemma.
Here’s a tried and true way to determine how efficient your old filter is (NOTE: To avoid a big mess, we highly recommend conducting this test outside or over a protected surface): Position the filter horizontally, then with common table salt, start pouring the salt through the filter and see the quantity that comes out the other side. If some or all the salt falls through the filter, then you can imagine that the filter will let dust particles of similar size pass through. You should probably upgrade your filter to higher quality filter that is more efficient.
Home air filter selection depends primarily on three factors: Size, material and MERV rating.
1) Filter Size
Unless you have the proper size home air filter, you will never enjoy the full effectiveness your system and filter can provide. 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 numerous standard width and height dimensions, and some systems have thicker filters.
2) Material & MERV Rating
MERV ratings are the efficiencies of the filter on a scale of 16. MERV stands for Minimum Efficiency Reporting Value. This number informs the user, under the least efficient conditions, how well the filter is designed to capture contaminants.
As a basic example, these are some common 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 provide better filtration efficiency, it is critical to understand that too high a MERV filter may also cost you more to operate your heating and air conditioning 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 goal is to get the right balance between air flow, air filtration level and energy efficiency.
Look at it this way, the most efficient ‘filter’ would equivalent to a piece of plywood that prevents ALL contaminants and all the air from getting into your Charlotte home. That's maximum 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 on the advice of your Komfort Air technician to verify 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 suffers from allergies or respiratory problems and a high MERV rated filter is required, consider a whole-home air filtration solution that will meet your energy and filter efficiency needs.
Filtration has changed significantly over the past ten years. Initially, home air filters were used in the furnace or air handler only to shelter the comfort equipment itself. But (in the words of Bob Dylan) the times they are a changing. Charlotte 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!