There are three basic tiers of air filtration for keeping the air circulating through the heating and cooling system clean, comfortable and healthful:
Standard filters such as those made of disposable fiberglass and washable metal mesh are the least expensive of all air filters. They are designed to catch only the larger and more visible particles of dust and dirt that circulate through a forced air system. For many homeowners, standard filters are sufficient to meet their expectations of indoor air quality for the home, and confer the added convenience of replacements being available off the shelf and serviceable by anyone. Efficiency is about 3 to 5 percent according to standard industry measures.
Media filters can remove very small particles that require an optical microscope to be seen individually — such as pollen, lint, dust plant spores, cooking grease, and some tobacco and cooking smoke. They are more effective than standard filters, and are more expensive, but find favor with homeowners who struggle with allergies and asthma. The filtering material must be replaced at least annually and is not typically available from stores, requiring a visit from your trusted heating and air conditioning contractors. Efficiency is about 25 to 35 percent.
Electronic air cleaners are the most expensive of all air filters, but are also the most efficient. If allergens and asthma afflict you more profoundly, an electronic system is the strongest, most active line of defense. Unlike standard or media air filters that passively catch relatively large particles as they pass through, electronic air cleaners attract and retain pollutants like a powerful magnet.
Using electrostatic precipitation principles, Electronic air cleaners are even effective on particles so small that an electron microscope would be required to see them. While the larger particles of dirt are trapped by the screen pre-filter, the smaller microscopic particles (as small as one micron) undergo an ionizing process that imparts on them an electrical charge, which in turn traps them on charged collector plates. Electronic air cleaners are 10 to 20 times more efficient than standard filters as they remove up to 95 percent of the dirt, dust, and smoke that would otherwise circulate through the air.
Electronic air cleaners also are energy efficient — most require no more power per day than a 40-watt light bulb. They feature permanent aluminum “cells” that can be rewashed in a dishwasher or laundry tub and reused almost indefinitely.
Whichever kind of air filtration you may be considering, contact Comfort Control Heating and Air Conditioning for any consultation, installation and maintenance needs.