Just go to any home improvement store and the choice of home air filters can be dizzying. What’s the best one? Does the price reflect the quality? These are just a few of the questions that make selecting home air filters so mind-boggling. Let Broad Ripple Service Experts Heating & Air Conditioning try to help you de-mystify the air filter dilemma.
Here’s an easy way to determine how efficient your old filter is (NOTE: To avoid a big mess, we highly recommend conducting this test outside or over a protected surface): Position the filter horizontally, then using everyday table salt, start pouring the salt through the filter to see how much 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 an air filter that’s more efficient.
Home air filter selection depends primarily on three factors: Size, material and MERV rating.
1) Filter Size
Purchasing a properly sized air filter for your Indianapolis home is important. Simply look at the label of your existing filter to see the dimensions, or just measure it yourself. Most 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
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 trap contaminants.
As a basic example, these are some usual MERV ratings and how they relate to efficiencies. This is only a guide, so make sure you 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 ensure better filtration efficiency, it is extremely important to understand that too high a MERV filter may also require more to operate your heating and air conditioning 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 actually be a piece of plywood that would just trap ALL contaminants and all the air from entering your Indianapolis home. That's all-out air filtration, but would also be a terrible way to live.
Your best bet for most systems would be a MERV 6-8. A higher MERV filter should be used subject to the advice of your Broad Ripple Service Experts Heating & Air Conditioning technician to confirm your system has the capability of moving the suitable volume 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 deals with allergies or respiratory problems and needs a high MERV air filter, consider a whole-home air filtration solution that will meet your energy and filter efficiency needs.
Filtration has changed significantly 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. Indianapolis 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!