How often should a person change the filter in a heating and cooling system?

Your heating and cooling system's air filters should be changed or cleaned at least once a month says Annette Floridia, a customer service representative for Precision Aire. "We do not recommend those cheap blue filters. We recommend a white treated filter or a permanent filter. These are more effective at keeping the dirt, hair, and other debris out of your system and air ducts. They cost more money, but filters are very important to the functioning of your heating and air conditioning system. If your filter is clogged it causes your electric bills to go up and can cause your system to freeze up. You could have problems with your system not functioning properly by having a dirty or ineffective filter," she says.

She recommends investing in a permanent filter, which can be found at most home improvement and hardware stores. The price for permanent filters begins at about $15 and they are very simple to clean. Floridia suggests washing them off outdoors with a garden hose and allowing them to dry in the sun. You can also purchase a permanent filter that acts as an electronic air filter like the ones sold by Trane dealers. The Trane Whole House Electronic Air Filters have a tray that slides out for cleaning and never need to be replaced.

Keeping your filter clean and in good working order is the most important step in an efficient and properly functioning heating or cooling system. A clean air filter also increases the quality of the indoor air you and your family are breathing everyday.

When preparing to replace or clean your air filter, first make sure that the system is turned off. If you need to know the size filter that is needed, you should see a number written on the old filter or you can take the old filter with you to the hardware or home improvement store to ensure you find the appropriate size. You will find a number of choices in air filters ranging from disposable fiberglass filters to electronic air cleaners. The Louisiana Cooperative Extension Service suggests that 2-inch filters are not necessarily better than 1-inch filters; they just "hold more dust". Electrostatic filters may be a good choice for removing allergens from the air but also require more frequent cleaning than other types of air filters. If you are buying a permanent air filter that requires cleaning it is advisable to ask for a demonstration of the proper cleaning procedure before purchasing.

It is very important that your filter fit well, both for the system's efficiency and the health of your indoor air. If the filter has arrows imprinted on it, it should be placed so that the airflow follows the direction of the arrows. If there is no direction indicated, the reinforced surface should be placed against the air conditioning unit.

After cleaning or replacing your filter, this is also a good time to check your condensation drain line. If water does not flow freely through it you may need to use a designated line cleaner to clear the line.