Air Filtration

No matter if you are heating your indoor air in the winter or cooling it down in the summer time, filtration matters. For your indoor air comfort and health, along with the health of your system, Snelling Company recommends annual duct cleaning and replacement of your air filter as needed every 3-6 months to be key to your home system’s general maintenance.

Doing so helps with the life and longevity of your system and also is proactive, meaning you experience lesser likelihood for costly repairs in the future with simple steps.

Snelling Company notes there are three primary factors used in picking the right air filter for your home comfort system: Filter Size, MERV Rating and Material

1) Filter Size

Take a look at the label of your existing filter to see the proper measurements or measure the width and length of the filter cavity. Most home air filters start at 1” thick, but modern furnace designs have numerous standard 4-6” width and height dimensions, and some systems have much thicker filters.

2) MERV Rating

The efficiencies of filters are rated on a scale up to 16, known as MERV ratings.

MERV stands for Minimum Efficiency Reporting Value. This number identifies for the homeowner, under the least efficient conditions, how well the filter is designed to hold contaminants (i.e. dust particles, hair and dirt- the things you don’t want to breathe)

These are some typical MERV ratings and how they correspond to efficiency.

Be sure to read the filter manufacturers’ information when shopping and purchasing your system’s specified filter.

Sample MERV Ratings | Average Filtration Efficiencies

MERV 1-4 60-80%
Fiberglass, Disposable Panel, Washable Metal or Synthetic, Self-Charging (Passive Filter)

MERV 5-8 80-95%
Pleated, Media panel, Cube

MERV 9-12 >95%
Extended pleated

MERV 13-16 >98%
Electronic

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 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.

3) Material

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 coming inside your home. That’s all-out air filtration, but would also be a terrible way to live. Fiberglass, Disposable Panel, Washable Metal or Synthetic, Self- Charging (Passive Filter) are all options for helping to filter the air coming through your system. They each have a different MERV value and are manufacturer differently as well.

A default choice for most heating and cooling systems would be a MERV 6-8. A higher MERV filter should be used based upon the advice of a Snelling Company technician. We want to confirm your system has the capability of moving the suitable volume of air through higher efficiency filters.

Do not sacrifice your energy-efficiency for filter efficiency.

Snelling Company knows that you really need a balance of the two.

However, if you have allergies or respiratory problems and need a high MERV 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 few years. Initially, home air filters were used in the furnace or air handler only to protect the comfort equipment itself.

Today, homeowners are more likely to prevent experiencing most indoor air quality problems with the selection of the right filter and scheduling general maintenance.