The most efficient way to filter household air is through forced-air heating or central air-conditioning. Filters are built into the return-air duct work, trapping particles as air passes through. These kinds of systems are considered passive hen the fan is running because they are constantly filtering the air in the home. Whole house filters come in four main types.
If you have a forced air furnace, you already have a rudimentary air-filtration system. That matted, fiberglass filter that needs to be changed once a month is designed to protect your furnace from large dust particles. But while they might keep surfaces in your home a bit cleaner, they don’t block the microscopic particles that are actually most irritating to lung tissue. Pleated filters, which pack more material in the same amount of space cost a bit more and do a slightly better job. However, the best pleated filters are electrostatically charged to attract allergens like pollen and pet dander. They should be changed every two to three months.
Extended Media Filters
Picture a stack of furnace filters about eight inches thick and you’ll get the idea of an extended media filter. The boxy units contain an accordion like pile of filtration media, making them more effective than regular fiberglass filters. They require professional installation because the large filter holder has to be installed into the duct work. They cost considerably more than a flat filter but are much more convenient and longer lasting, since they only require yearly replacement.
Sometimes referred to as electrostatic precipitators, these high tech units are also incorporated into the duct work. As air passes through, a high voltage current puts an electrical charge on particles. At the other end of the unit, oppositely charged collector plates grab the particles like a magnet. Electronic filters work especially well on smoke particles which are too small to be trapped in media filters. One independent test found electronic filters worked about 30 times more efficiently than regular fiberglass filters. (There is no industry yardstick for measuring the effectiveness of whole-house units, because performance is affected by a home’s blower and duct work.) Unlike media filters, electronic filters never need replacing, but the aluminum collector plates must be cleaned in soapy water every few months. The process of charging particles is referred to as ionization and may produce trace amounts of ozone, a lung irritant.
People concerned about germs are advised to consider an ultraviolet filter. Typically, UV filters are built-in components and are sold as add-ons to a whole –house electronic precipitator. They cost anywhere from $400 to $800. The ultra-violet light zaps airborne bacteria and viruses into oblivion, which is why hospitals use UV air filters in tuberculosis wards. Of course, the bug has to reach the filter before it can be zapped. If someone sneezes in your face, UV technology won’t help.
Call Bash Heating and Cooling at 1-866-808-0471 today for a free no obligation consultation and see what we can do to improve your home comfort.