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 two of many of the questions that make purchasing air filters for your home mind-boggling. Let Rob's Albertan Service Experts attempt to resolve your home air filter questions and allow you to continue enjoying the comfort of your home without concern.
Here’s a tried and true way to figure out 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): Hold the filter horizontally, then taking common table salt, start pouring the salt through the filter to 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 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 height by width and thickness, 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 informs the user, under the least efficient conditions, how well the filter is designed to capture contaminants.
As a basic example, these are some typical MERV ratings and how they connect 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%
Extended pleated
MERV 13-16 >98%
Electronic
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 HVAC system. The higher the MERV, the less 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.
Think about it this way, the most efficient ‘filter’ would equivalent to a piece of plywood that prevents ALL contaminants and all the air from entering your Edmonton home. That's definitely the “best” 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 on the advice of your Rob's Albertan Service Experts technician to ensure your system has the capability of moving the suitable volume of air through higher efficiency filters. You generally 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 needs a high MERV air filter, consider a whole-home air filtration solution that will satisfy your energy and filter efficiency needs.
Filtration has changed considerably over the past ten years. Initially, home air filters were used in the furnace or air handler only to safeguard the comfort equipment itself. Today it’s a whole new ballgame. Edmonton area homeowners expect their air filter to save kids from a wide variety of harmful pollutants, dust mites, and even prevent the need for dusting. Dare to dream!