The right furnace filter
Listed below are some of the most common furnace filter types.
- Disposable fiberglass filters are the least expensive – and also the least effective, designed to block only large dust and dirt particles to protect your furnace. Smaller particles, like pollen and mold, pass right through.
- Washable “electrostatic” filters have a static charge that attracts dust, dirt and other matter. These filters are slightly more effective than disposable, but still block only 15 to 20 percent of airborne particles.
- Pleated “allergy” filters use a much denser mesh material to trap particles. The pleats increase the surface area, eliminating large allergens like pollen and mold – most are 35 to 50 percent efficient.
- Electronic air cleaners use electrodes to create an ionized electrical field that “magnetizes” pollutant particles and collects them on the filter material. An electronic unit can eliminate virtually all pollen and mold spores, up to 94 percent of smaller particles, and even up to 80 percent of airborne viruses.
Tips and Warnings:
- To keep the air in your home healthy, replace your furnace filter monthly during chilly months and at least once a season.
- Be sure you turn off the furnace before opening the front panel.
- Do not use the furnace until a clean filter is installed.