Save Energy With New Furnace & AC Filters

"Keeping the filter clean can lower your air conditioner's energy consumption by 5% - 15%."

The most important maintenance task that will ensure the efficiency of your air conditioner is to routinely replace or clean its filters. Clogged, dirty filters block normal air flow and reduce a system's efficiency significantly. With normal air flow obstructed, air that bypasses the filter may carry dirt directly into the evaporator coil and impair the coil's heat-absorbing capacity. Keeping the filter clean can lower your air conditioner's energy consumption by 5% - 15%.

For central air conditioners, filters are generally located somewhere along the return duct's length. Common filter locations are in walls, ceilings, furnaces, or in the air conditioner itself. Room air conditioners have a filter mounted in the grill that faces into the room.

Some types of filters are reusable; others must be replaced. They are available in a variety of types and efficiencies. Clean or replace your air conditioning system's filter or filters every month or two during the cooling season. Filters may need more frequent attention if the air conditioner is in constant use, is subjected to dusty conditions, or you have fur-bearing pets in the house.


"Replace your filter at the stated intervals"

  1. Start by reading the manufacturers' instructions on maintaining your furnace to determine where the filter is located and also how often you should have your furnace inspected by a licensed heating contractor.
  2. Identify from the instructions the type of filter appropriate for the furnace you have.
  3. When you purchase your filters, look for the highest-efficiency filter that works with your furnace.
  4. Replace your filter at the stated intervals, usually about every three months. Replace more often if you are introducing higher levels of particulates into your home, such as when renovations are being done, when using candles, or if someone has been smoking in your house. Also, consider more frequent replacements if you have a family member with asthma, allergies or other lung diseases.


"Filters should be replaced on a regular basis"

Use filters to remove particles from the air stream. Filters should be replaced on a regular basis, on the basis of pressure drop across the filter, or on a scheduled basis. Fans should be shut off when changing the filter to prevent contamination of the air. Filters should fit tightly in the filter housing. Low efficiency filters (ASHRAE Dust Spot rating of 10%-20%), if loaded to excess, will become deformed and even "blow out", leading to clogged coils, dirty ducts, reduced indoor air quality and greater energy use. Higher efficiency filters are often recommended as a cost-effective means of improving IAQ performance while minimizing energy consumption. Filtration efficiency should be matched to equipment capabilities and expected airflows.