You’ve probably experienced the feeling of confusion when trying to select the correct home air filter for your needs. What’s the best one? Does the price reflect the quality? These are just two of many of the questions that make selecting home air filters so mind-boggling. Let Service Experts Heating & Air Conditioning attempt to resolve your home air filter questions and allow you to continue enjoying the comfort of your home without concern.
Here’s a simple way to tell how efficient your old 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 standard 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 know that the filter will let dust pass through as well. You should probably upgrade your filter to something more efficient.
There are 3 primary considerations when choosing a household air filter; Size, Material and MERV rating.
1) Filter Size
Purchasing a properly sized air filter for your Roanoke home is important. Simply look at the label of your existing filter to see the proper measurements, or just measure it yourself. The majority of 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
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 contain contaminants.
To explain MERV ratings more impactfully, these are some usual MERV ratings and how they correspond to efficiencies. This is only a guide, so make sure you 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%
Extended pleated
MERV 13-16 >98%
Electronic
Be Careful About High MERV Ratings
While a higher MERV number may provide better filtration efficiency, it is extremely important 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 difficult 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.
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 Roanoke home. That's all-out air filtration, but would also be the least comfortable way to go.
Your best bet for most systems would be a MERV 6-8. A higher MERV filter should be used on the advice of your Service Experts Heating & Air Conditioning representative to ensure your system has the capability of moving the proper quantity of air through higher efficiency filters. You probably do not want to lose energy-efficiency for filter efficiency; you want a balance of the two. However, if your family deals with 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 significantly over the past ten years. Initially, home air filters were used in the furnace or air handler only to safeguard the comfort equipment itself. But (in the words of Bob Dylan) the times they are a changing. Roanoke area homeowners expect their air filter to save children from a wide variety of harmful pollutants, dust mites, and even prevent the need for dusting. Dare to dream!