An effective HVAC air filter is essential to good indoor air quality and the operating efficiency of your home’s forced-air heating and cooling system. A dirty air filter will reduce the energy efficiency of HVAC equipment, and also contribute to poor indoor air quality.
Ideally, an HVAC filter should be inspected monthly. If it looks dirty, it should be replaced or, if it's reusable, cleaned. During the heavy-use seasons – winter and summer – they might need to be changed as often as monthly. Specific conditions in your home – long-haired pets, a dusty environment, heavy use of cooling or heating – can require more frequent filter changes. If you’re ready to go air filter shopping, but are unsure of the differences between filters, review the information below. The higher the air filter's Minimum Efficiency Reporting Value (MERV) rating, the smaller the airborne particulate the air filter will capture. Filters with high-end MERV ratings, however, are generally not recommended for residential use, because they restrict airflow, something you want to avoid for efficient A/C, heat pump or furnace operation.
Types of Filters
- High efficiency air filters have superior ability to trap unwanted air particles, partly because of their pleated filter paper or synthetic polyester fiber construction. Because they are capable of trapping even tiny dust particles, they are often used in sterile or near-sterile environments like hospitals. For home use, they likely will require actual physical modifications of your HVAC system.
- Pleated air filters are constructed with an accordion-style surface that features alternating peak and valley surfaces for trapping undesirable particles. Usually the pleated surfaces are protected by a thin metal frame of aluminum or other light metal, and this construction provides very good particle trapping capability. While air filter shopping, keep in mind that these offer a desirable blend of maintaining air quality and proper system airflow.
- Fiberglass filters are most often constructed of a single flat-panel surface constructed of fiberglass or spun glass, which is effective in trapping larger particles from the air. Mainly intended to protect the heating/cooling system, they are not effective at maintaining indoor air quality.
- The better grades of washable filters are constructed of an inner core with open cells. These are good at trapping particles and are able to withstand repeated cleanings. However, their MERV ratings are usually relatively low, and they may harbor mold and bacteria.
If you need expert advice on any home comfort systems, please contact us at Hartman Brothers Heating & Air Conditioning. Since 1963, we have been serving the greater New Haven/Fort Wayne area of Indiana.
Our goal is to help educate our customers in New Haven, Indiana and surrounding Fort Wayne area about energy and home comfort issues (specific to HVAC systems). For more information about air filters and other HVAC topics, download our free Home Comfort Resource guide.
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