Air filters are essential components of your heating and cooling system. They help improve the quality of your home’s air and keep your system performing at peak efficiency. The most common air filters are standard disposable cartridges, but advanced filtration systems and air cleaners are also available.
Standard, one-inch disposable air filters should be changed every three months. However, if anyone in your family suffers from allergies, or if you have pets or dust buildup in your home, you might want to change your filters every month or so. Advanced filtration systems have longer life spans and are usually maintained by HVAC professionals.
The process for changing standard disposable filters is fairly straightforward and involves just a few steps:
Locate your air filter Air filters are typically located in your system’s return air vent, which might be on the ceiling, wall or on the side of your furnace or air handler. Your air filter might also be housed inside the unit. If this is the case, you may have to remove an access panel to get to the filter.
Remove the air filter from its housing Simply open the return and pop out the old filter. If there is no filter in the return, measure the length and width of the space, so you’ll know what size filter you’ll need for replacement.
Note the size printed on the air filter frame If you removed an old filter, check its size so you can be sure you have the correct filter for replacement. If you have any questions about the size you need, you can refer to the owner’s manual for your furnace or air handler, or contact your local Lennox® Dealer.
Install the new air filter Securely slide the new filter in place of the old one, making sure you follow the arrows printed on the sides of the filter frame. These arrows point to the direction of the airflow, which should be toward your furnace or air handler.
Get help from your lennox® dealer If you have any questions about where your filter goes, or how to install a new one, your local Lennox® Dealer can help. If you have already replaced your filter, and your system makes excessive noise, contact your Lennox® Dealer to address the problem.
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*Leading consumer magazine, January 2012. Based on the published CADR, which is a standardized measurement system to determine the cubic feet of clean air produced per minute.
**U.S. Environmental Protection Agency, "Ozone Generators that are Sold as Air Cleaners: An Assessment of Effective and Health Consequences," August 2006
***According to Title 24 Code in California, MERV 11 filters cannot be used in new equipment installs. Code dictates a new system shall be provided with air filter(s) having a designated efficiency equal to or greater than MERV 13 when tested in accordance with ASHRAE Standard 52.2.