What you should know about refrigerator water filters
Surveys show that many Americans do not consume sufficient water. They prefer bottled drinks in part because they complain about the taste of water. Water can taste bad because of the presence of contaminants. The fact is, using refrigerator water filters can improve the taste of water and remove contaminants while being more economical than bottled water.
Many refrigerators sold in the market today have ice makers as well as refrigerator water filters and dispensers built in. In earlier years, filters were present only in high-end models, but these days with increased competition, they have become quite common.
These refrigerators are connected directly to the water supply, often via a copper pipe at the back. The water filter is normally present inside the cabinet, or in some cases, in the bottom tray.
What if your refrigerator has an ice-maker but does not have a built-in water filter? In such cases, it is usually possible to install a water filter. The solution is simple - the water filter is installed in the line that supplies water to the refrigerator. Keep in mind that all filters need to be changed periodically and so the external filter should be installed in an easy-to-access location.
Many refrigerator water filters use granular activated carbon (GAC) for filtration. Carbon is capable of absorbing many impurities present in tap water and well water. Chlorinated water supplied by town water systems often has a bad odor - this can be removed by carbon filters. These filters however, are not capable of removing many potentially dangerous contaminants like heavy metals, bacteria and several kinds of chemicals.
Filters in units using GAC must be changed every six months (or more frequently if the manufacturer specifies it). This is important because both chemical contaminants and bacteria can build up within GAC. As a result, if the filters are not replaced on schedule, you may end up with a situation where the output of filtered water is actually more contaminated than unfiltered tap water.
Other refrigerator water filters use solid carbon blocks instead of GAC for filtration. When compared to GAC, carbon block filters can absorb more contaminants including pesticides and other toxins. This is partly because water strains through carbon blocks at a slower rate than through carbon granules.
Unfortunately, solid carbon block filters cannot absorb sulfides and nitrates (which come from fertilizer residues), heavy metals and other dangerous contaminants.
There are some refrigerator water filters that use fiber filters. These filters are made of spun cellulose or rayon closely wrapped together. While these filters can trap dirt, rust, lead, etc, they cannot remove much of the dangerous impurities present in water. For this reason, it is usually not advisable to use fiber filters as the only filtration method. They can be used in combination with carbon and other filters to improve the filtration achieved.
From the perspectives of both cost and safety, using refrigerator water filters makes sense, particularly when compared to using bottled water. Many homes make use of these filter systems in preference to bottled water, which is often just ordinary tap water anyway.