Air Filters: In 2014 I purchased a Lennox XC-21 HVAC system (*) with a PureAir™ Air Purification System that includes a MERV 16 rated air filter, two UVA lamps, and a titanium dioxide catalytic surface (*). The PureAir features and benefits include: reliable performance; industry-exclusive air purification technology; whole-home purification works with your existing heating and cooling system; only single indoor air quality system to attack all three classes of indoor air contaminants; small, breathable particles such as dust, dirt, pollen and allergens; airborne mold spores, bacteria and viruses; odors and chemical vapors; MERV 16 PrecisionPleat™ media filter; removes OVER 95% of particles ranging in size down to 0.3 micron; removes OVER 90% of bioaerosols ranging in size down to 0.01 micron; removes and destroys approximately 50% of household odors and chemical vapors in a 24-hour period; hospital inpatient care/general surgery level filtration; reduces and destroys ozone—a product of pollution and a known lung irritant; MERV = Minimum Efficiency Reporting Value. Describes the filter's ability to capture particles and ranges from 1 to 16. Typical fiberglass filter = MERV 1. The higher the MERV rating, the better the filtration. One micron = 1/25,000 of an inch in diameter. From the Frequently Asked Questions page: How does the PureAir™ air purification system work? The PureAir system reduces concentrations of pollutants through a process called photocatalytic oxidation (PCO). Similar to the process used by the Department of Defense to combat germ warfare, PCO combines nature's three most powerful air purifiers: Ultraviolet light; Titanium dioxide, a nontoxic substance found in the earth's crust; Hydroxyl radicals, particles derived from hydrogen peroxide. The PureAir PCO process involves three steps: The pleated media filter captures particles and bioaerosols like pollen and pet dander, removing them from the airstream. As the odor- and chemical-filled airstream flows over the UVA light, the airstream is exposed to the catalytic surface (titanium dioxide-coated mesh filter).
The light energy activates the catalyst, which generates hydroxyl radicals. These particles, which are more than twice as powerful as chlorine, break down the odors and chemicals into carbon dioxide and water.
