January 2005
Have You Checked Your Air Filter Lately?

How often do you change the gas furnace's air filter – once a month, every other month or twice a year? You can increase your heating system's energy efficiency simply by replacing your home's air filters regularly.

Walton EMC Marketing Specialist Dan Guy says it's common to see a $15 to $50 increase in your monthly energy bill from dirty air filters.

"You should change or clean your air filters religiously – every month," Guy says.

Air filters help remove dust, pollen and other particles from your home's air. Filters improve the quality of the air you breathe. Dirty air filters restrict airflow and increase the humidity level in your home.

Most air filters are inexpensive considering their value to your heating system. You can determine which filter to use based on its efficiency and how often you want to change the filter. The filter's efficiency depends on the type, size and number of particles it can trap.

Throwaway filters are the cheapest, but only trap larger particles. This type consists of fiberglass or polyester and must be disposed monthly.

Washable filters may be friendlier to the environment but require more effort to maintain. Instead of disposing the filter each month, it must be cleaned. There are two types: electrostatic or non-electrostatic washable filters.

Compared to non-electrostatic filters, electrostatic filters last longer and trap particles better than throwaway and washable filters. Some electrostatic filters offer a lifetime warranty. These filters contain electrostatic fibers. The fibers, similar to magnets, attract smaller particles other filters let through. Washable filters cost slightly more than disposable types, but the price is fairly competitive considering the lifespan of the filter.

Pleated, or cartridge-type, filters trap more particles than other types due to the filters' thickness and large surface area. Their efficiency ratings are higher than disposable filters, and therefore cost more. But the filter only needs changing once a year.

Electronic filters, also called electronic air cleaners, are the most efficient. Air particles have a positive electrical charge, while the ground plates in an electronic filter are negatively charged. As the particles pass through the system, the two charges attract. As the air particles attract to the ground plate, they're immediately removed from the air.

This type of system removes the most unwanted particles from the air compared to other models. The cost is considerably higher. Is it worth the extra cost? Once you consider the advantages and disadvantages of all types, you'll decide which type you prefer. If you want a filter that requires little to no maintenance, then the electronic filter is the answer.

Another way to evaluate all types of filters is by comparing the Minimum Efficiency Reporting Value (MERV). It measures the filters' filtration ability. Filters are rated with a score between one and 16. Higher scores mean better filtration. You can purchase air filters at any home improvement store, hardware store, discount chain or grocery store.

Pick a day each month for replacing or cleaning the air filter. It's easy to forget, so mark your calendar in advance. If you use throwaway filters, plan ahead by purchasing 12 at a time. You'll have a year's supply and no longer have an excuse for not replacing your old filter.

Decide which type filter will work best for you and replace your old air filter so you can increase your home's efficiency and start saving money on your energy bill.