You’ve probably experienced the feeling of confusion when trying to select the correct home air filter for your needs. Which brand is best? Is the more expensive products worth the investment? These are just a few of the questions that make the selection mind-boggling. Let McKinley Heating Service Experts try to help you de-mystify the air filter dilemma.
Here’s a tried and true way to figure out how efficient your current filter is (NOTE: Do this outdoors or with something below the filter so you don’t end up with a mess): Set the filter horizontally, then using common table salt, begin to pour the salt through the filter and see the amount 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 that same size flow through. You might want to upgrade your filter to something 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. Typically 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
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 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 buying 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 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 less the air may flow through the system, and the harder the system may need to work. Your aim is to get the right balance between air flow, air filtration level and energy efficiency.
Think about it this way, the most efficient ‘filter’ would probably be a piece of plywood that stops ALL contaminants and all the air from getting into your Edmonton home. That's maximum air filtration, but would also be like living in a box.
Your best bet for most systems would be a MERV 6-8. A higher MERV filter should be used based upon the advice of your McKinley Heating Service Experts technician to confirm your system has the capability of moving the proper volume of air through higher efficiency filters. You normally do not want to give up 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 satisfy your energy and filter efficiency needs.
Filtration has changed significantly over the past few years. Originally, home air filters were used in the furnace or air handler only to protect the comfort equipment itself. The story is different today. Edmonton area homeowners expect their air filter to save loved ones from a a growing list of harmful pollutants, dust mites, and even prevent the need for dusting. Dare to dream!