You’ve probably experienced the feeling of confusion when trying to select the correct home air filter for your needs. Which brand is best? Does the price reflect the quality? These are just two of many of the questions that make the selection mind-boggling. Let Climate Control Service Experts 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): Position the filter horizontally, then using standard table salt, pour the salt through the filter then 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 particles of similar size pass through. You really should 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
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. The majority of 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 informs the user, under the least efficient conditions, how well the filter is designed to capture contaminants.
To explain MERV ratings more impactfully, 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 shopping for 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 ensure better filtration efficiency, it is very important to understand that too high a MERV filter may also require more to operate your furnace and AC 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 probably be a piece of plywood that prevents ALL contaminants and all the air from coming inside your Mobile home. That's maximum air filtration, but would also be a terrible way to live.
The default choice for most systems would be a MERV 6-8. A higher MERV filter should be used on the advice of your Climate Control Service Experts representative to ensure 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 the situation necessitates a high MERV rated air filter, consider a whole-home air filtration solution that will meet your energy and filter efficiency needs.
Filtration has changed greatly 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. Mobile area homeowners expect their air filter to save children from a a growing list of harmful pollutants, dust mites, and even prevent the need for dusting. Dare to dream!