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Changing Water Filters

Learn when and why you need to change your water filter.

Water filtration systems come in many shapes and sizes. But no matter where the filtration device is installed, it will likely use filter media that needs to be replaced regularly.

Why Do Filters Need to Be Changed?

Many filtration systems use carbon, charcoal or a blend of filter media to help reduce impurities. These systems generally reduce contaminants in one of two ways.

First, some contaminants are filtered mechanically, meaning they are large enough to be trapped in the pores of the filter. Other contaminants adhere to the surface of the filter media. Eventually, the surface area of the filter media becomes filled and no more contaminants can be adsorbed. Or, in the case of mechanical filtration, the pores of the filter become so clogged with debris that water is unable to move through the filter effectively.

While the latter is easy to spot, since the flow rate of the water being produced by the system slows dramatically, it's not as easy to tell when the surface area of the filter media has become full and needs to be changed.

How Often Should Filters Be Changed?

The recommended filter change cycle varies from product to product. Home filtration systems usually have established “service cycles.”

The service cycle may be for a specific number of gallons or an estimate of the number of months that a cartridge will last in the average home. To ensure the filter continues to reduce contaminants, replace it according to the manufacturer’s recommendations.

Choose the Right Replacement Cartridge

Filter cartridges are not necessarily universal. While a non-certified cartridge may look similar in size and even appear to fit inside the housing of a water treatment system, even the smallest size difference could allow water to go around the cartridge rather than through it.

In addition, non-certified filter cartridges may not be of the same quality as the manufacturer's suggested replacement. This could result in the water not being filtered effectively or the possible introduction of impurities into the water from materials that were never verified to be acceptable for drinking water contact.

To ensure the adequate performance of your water treatment system, use the proper replacement cartridge and change your filter at the recommended interval.

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