Just go to any home improvement store and the choice of home air filters can be dizzying. What’s the best one? Should you just get the cheapest? These are just a few of the questions that make purchasing air filters for your home mind-boggling. Let Peachtree Service Experts try to help you de-mystify the air filter dilemma.
Here’s a tried and true way to determine how efficient your existing filter is (NOTE: Spare yourself a huge mess by conducting this experiment outside or with something below the filter to help keep things clear): 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 pass through as well. You should probably upgrade your filter to higher quality filter that is more efficient.
Size, MERV rating and material – these are the three primary factors used to pick the proper air filter for your home.
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 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 tells the user, under the least efficient conditions, how well the filter is designed to trap contaminants.
To explain MERV ratings more impactfully, these are some usual 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 very important to understand that too high a MERV filter may also take 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 objective should be to get the right balance between air flow, air filtration level and energy efficiency.
Consider it this way, the most efficient ‘filter’ would probably be a piece of plywood that would just trap ALL contaminants and all the air from entering your Atlanta home. That's all-out air filtration, but would also be the least comfortable way to go.
The default choice for most systems would be a MERV 6-8. A higher MERV filter should be used subject to the advice of your Peachtree Service Experts representative to verify your system has the capability of moving the suitable amount of air through higher efficiency filters. You normally do not want to lose energy-efficiency for filter efficiency; you want a balance of the two. However, if your family has allergies or respiratory problems and needs a high MERV 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 several years. In the beginning, home air filters were used in the furnace or air handler only to protect the comfort equipment itself. But (in the words of Bob Dylan) the times they are a changing. Atlanta area homeowners expect their air filter to save children from a whole host of harmful pollutants, dust mites, and even prevent the need for dusting. Dare to dream!