The term “filter kettle” most commonly refers to a tea kettle with water filtration technology. These kettles are designed to be filled with tap water, but boil and deliver filtered, purified water. There are many different sorts of filter kettles, but most are portable, and the vast majority are electric.
Health experts have long advocated the use of home water filtration systems, particularly in areas with hard water or in homes with aging pipe structures. Impurities often seamlessly enter the water stream. Not all impurities are harmful, but they often affect the taste of water and can lead to health complications with continued exposure. Using filter kettles saves the step of filtering the water before boiling it.
Filter kettles typically also promise to resist limescale and staining. Mineral-rich water often leeches certain deposits, typically calcium, magnesium, and other salts, when boiled. These minerals form white crystals or stains, known as limescale, on the sides of kettles. Filtering the water before boiling it is one of the only ways to prevent limescale formations. Once the deposits are made, they can be very difficult to remove.
A filter kettle is a water filter and kettle in one. Most models work by pushing tap water through a heat-resistant filter, then heating that water in a chamber below. Filter kettles are almost exclusively electric, and most are programmed to automatically shut off once the water reaches a boil. An electric kettle both prevents overheating and prevents direct exposure of any of the kettle’s parts to heat sources.
Many models are cordless, as well. A cordless electric kettle sits atop a base unit that is generally plugged in to a wall socket. The advantage to a cordless filter kettle is that it can quickly be detached from its base, then used as an ordinary kettle would be: it can be brought to the table, passed from person to person, or otherwise moved about with relative ease.
The most common kettles are made primarily of plastic. These are usually quite cost-effective and are available from a variety of retailers. Higher-end models are often made of stainless steel. A steel kettle often lends a sleeker look, but there is rarely any tangible difference in its ability to filter and boil water.
Most of the time, the filters in a filter kettle are replaceable. Manufacturers typically recommend replacing the filters every 100 boils. Some of the most sophisticated kettles have “filter health” meters on their lids or sides, which indicate when a replacement is needed.
In some instances, the term “filter kettle” can also refer to a kettle not with a water filtration system, but with a built-in tea or coffee filter. These are more commonly known as brewing kettles or infuser kettles. The kettles work as a one-step means of brewing a cup of coffee or loose-leaf tea.