Change Your Furnace Filter Monthly This Winter

Although many furnace manufacturers recommend changing the furnace filter only twice yearly, the demands of good indoor air quality, energy efficiency, and proper airflow call for more frequent changes.

In general, the type of filter may not be as important as its cleanliness. That is, unless there are allergies or COPD- related conditions suffered by any of the family members. In which case there would arise a need for more expensive HEPA-type filters (about $10-$12) apiece.

As the furnace filter catches more particles of dirt, dust, etc..., the filter surface's free space decreases, which thereby decreases its ability to let air pass through. When airflow is restricted, not only is the energy efficiency of the central unit affected, but the air quality and the home efficiency in general decreases as well. Also, as the size and number of particles on the filter grows, its ability to retain them decreases, allowing them to escape into the ductwork and, ultimately back into the house.

When compared to the cost of ductwork cleaning, higher power bills due to less efficient furnaces, shorter life of the central unit due to poor air flow and inefficiency, and extra air cleaning devices due to poor indoor air quality, the price of extra filters (about a dollar apiece for the cheap ones) is quite cost effective and sensible.