What Contaminants Are Removed by Whole-House Filters?

Common Contaminants Removed

Whole-house filters typically employ a combination of activated carbon and mechanical filtration media to capture contaminants. Activated carbon is effective against chlorine, volatile organic compounds (VOCs), and some heavy metals like lead and mercury. In contrast, mechanical filters can capture particulate matter, bacteria, and viruses. For example, a filter with a 1-micron nominal pore size can capture 99% of bacteria and 90% of viruses. Effective removal of these contaminants requires a filter with a sufficient surface area, typically in excess of 10 square feet.

Filter Media Options

Several types of filter media are commonly used in whole-house filters, including granular activated carbon (GAC), coconut shell carbon, and catalytic carbon. GAC is a cost-effective option for removing chlorine and VOCs, while coconut shell carbon is more effective against heavy metals like lead and mercury. Catalytic carbon, on the other hand, is designed to remove hydrogen sulfide and other sulfur-based compounds. When selecting a filter media, consider the specific contaminants present in your water supply and the desired level of filtration.

Filter Maintenance and Replacement

Regular maintenance and replacement of whole-house filters are crucial to ensure effective contaminant removal. Typically, filters need to be replaced every 6-12 months, depending on water usage and quality. During this time, the filter’s pressure drop can increase, indicating a reduction in contaminant removal efficiency. To optimize filter performance, monitor pressure drop, flow rates, and contaminant levels, and replace the filter as necessary.